Cannon Example

Simple Cannon example.

Cannon Screenshot 
# PySide6 tutorial 6


import sys

from PySide6.QtCore import Qt
from PySide6.QtGui import QFont
from PySide6.QtWidgets import (QApplication, QGridLayout, QLCDNumber,
                               QPushButton, QSlider, QVBoxLayout, QWidget)


class LCDRange(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        lcd = QLCDNumber(2)
        slider = QSlider(Qt.Horizontal)
        slider.setRange(0, 99)
        slider.setValue(0)
        slider.valueChanged.connect(lcd.display)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(slider)


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))
        quit.clicked.connect(qApp.quit)

        layout = QVBoxLayout(self)
        layout.addWidget(quit)
        grid = QGridLayout()
        layout.addLayout(grid)
        for row in range(3):
            for column in range(3):
                grid.addWidget(LCDRange(), row, column)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 9


import sys

from PySide6.QtCore import QRect, Qt, Signal, Slot
from PySide6.QtGui import QColor, QFont, QPainter, QPalette
from PySide6.QtWidgets import (QApplication, QGridLayout, QLCDNumber,
                               QPushButton, QSlider, QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning(f"LCDRange::setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)


class CannonField(QWidget):

    angle_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def paintEvent(self, event):
        painter = QPainter(self)

        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.blue)

        painter.translate(0, self.rect().height())
        painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16)
        painter.rotate(-self._current_angle)
        painter.drawRect(QRect(33, -4, 15, 8))
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange()
        angle.set_range(5, 70)

        cannon_field = CannonField()

        angle.value_changed.connect(cannon_field.set_angle)
        cannon_field.angle_changed.connect(angle.set_value)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addWidget(angle, 1, 0)
        grid_layout.addWidget(cannon_field, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        angle.setFocus()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.setGeometry(100, 100, 500, 355)
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 8


import sys

from PySide6.QtCore import Signal, Slot, Qt
from PySide6.QtGui import QColor, QFont, QPainter, QPalette
from PySide6.QtWidgets import (QApplication, QGridLayout, QLCDNumber,
                               QPushButton, QSlider, QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning("LCDRange.setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)


class CannonField(QWidget):

    angle_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def paintEvent(self, event):
        painter = QPainter(self)
        painter.drawText(200, 200, f"Angle = {self._current_angle}")
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange()
        angle.set_range(5, 70)

        cannon_field = CannonField()

        angle.value_changed.connect(cannon_field.set_angle)
        cannon_field.angle_changed.connect(angle.set_value)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addWidget(angle, 1, 0)
        grid_layout.addWidget(cannon_field, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        angle.setFocus()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.setGeometry(100, 100, 500, 355)
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 13


import sys
import math
import random

from PySide6.QtCore import (QPoint, QRect, QTime, QTimer, Qt, SIGNAL, SLOT,
                            Signal, Slot)
from PySide6.QtGui import QColor, QFont, QPainter, QPalette, QRegion
from PySide6.QtWidgets import (QApplication, QGridLayout, QHBoxLayout, QLabel,
                               QLCDNumber, QPushButton, QSizePolicy, QSlider,
                               QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, text=None, parent=None):
        if isinstance(text, QWidget):
            parent = text
            text = None

        super().__init__(parent)

        self.init()

        if text:
            self.set_text(text)

    def init(self):
        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)
        self.label = QLabel()
        self.label.setAlignment(Qt.AlignHCenter | Qt.AlignTop)
        self.label.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Fixed)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)
        layout.addWidget(self.label)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def text(self):
        return self.label.text()

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning(f"LCDRange::setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)

    def set_text(self, text):
        self.label.setText(text)


class CannonField(QWidget):

    angle_changed = Signal(int)
    force_changed = Signal(int)
    hit = Signal()
    missed = Signal()
    can_shoot = Signal(bool)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self._current_force = 0
        self._timer_count = 0
        self._auto_shoot_timer = QTimer(self)
        self._auto_shoot_timer.timeout.connect(self.move_shot)
        self._shoot_angle = 0
        self._shoot_force = 0
        self.target = QPoint(0, 0)
        self._game_ended = False
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)
        self.new_target()

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def force(self):
        return self._current_force

    @Slot(int)
    def set_force(self, force):
        if force < 0:
            force = 0
        if self._current_force == force:
            return
        self._current_force = force
        self.force_changed.emit(self._current_force)

    @Slot()
    def shoot(self):
        if self.is_shooting():
            return
        self._timer_count = 0
        self._shoot_angle = self._current_angle
        self._shoot_force = self._current_force
        self._auto_shoot_timer.start(5)
        self.can_shoot.emit(False)

    first_time = True

    def new_target(self):
        if CannonField.first_time:
            CannonField.first_time = False
            midnight = QTime(0, 0, 0)
            random.seed(midnight.secsTo(QTime.currentTime()))

        self.target = QPoint(200 + random.randint(0, 190 - 1), 10 + random.randint(0, 255 - 1))
        self.update()

    def set_game_over(self):
        if self._game_ended:
            return
        if self.is_shooting():
            self._auto_shoot_timer.stop()
        self._game_ended = True
        self.update()

    def restart_game(self):
        if self.is_shooting():
            self._auto_shoot_timer.stop()
        self._game_ended = False
        self.update()
        self.can_shoot.emit(True)

    @Slot()
    def move_shot(self):
        region = QRegion(self.shot_rect())
        self._timer_count += 1

        shot_r = self.shot_rect()

        if shot_r.intersects(self.target_rect()):
            self._auto_shoot_timer.stop()
            self.hit.emit()
            self.can_shoot.emit(True)
        elif shot_r.x() > self.width() or shot_r.y() > self.height():
            self._auto_shoot_timer.stop()
            self.missed.emit()
            self.can_shoot.emit(True)
        else:
            region = region.united(QRegion(shot_r))

        self.update(region)

    def paintEvent(self, event):
        painter = QPainter(self)

        if self._game_ended:
            painter.setPen(Qt.black)
            painter.setFont(QFont("Courier", 48, QFont.Bold))
            painter.drawText(self.rect(), Qt.AlignCenter, "Game Over")

        self.paint_cannon(painter)
        if self.is_shooting():
            self.paint_shot(painter)
        if not self._game_ended:
            self.paint_target(painter)
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()

    def paint_shot(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.black)
        painter.drawRect(self.shot_rect())

    def paint_target(self, painter):
        painter.setPen(Qt.black)
        painter.setBrush(Qt.red)
        painter.drawRect(self.target_rect())

    barrel_rect = QRect(33, -4, 15, 8)

    def paint_cannon(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.blue)

        painter.save()
        painter.translate(0, self.height())
        painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16)
        painter.rotate(-self._current_angle)
        painter.drawRect(CannonField.barrel_rect)
        painter.restore()

    def cannon_rect(self):
        result = QRect(0, 0, 50, 50)
        result.moveBottomLeft(self.rect().bottomLect())
        return result

    def shot_rect(self):
        gravity = 4.0

        time = self._timer_count / 40.0
        velocity = self._shoot_force
        radians = self._shoot_angle * math.pi / 180

        velx = velocity * math.cos(radians)
        vely = velocity * math.sin(radians)
        x0 = (CannonField.barrel_rect.right() + 5) * math.cos(radians)
        y0 = (CannonField.barrel_rect.right() + 5) * math.sin(radians)
        x = x0 + velx * time
        y = y0 + vely * time - 0.5 * gravity * time * time

        result = QRect(0, 0, 6, 6)
        result.moveCenter(QPoint(round(x), self.height() - 1 - round(y)))
        return result

    def target_rect(self):
        result = QRect(0, 0, 20, 10)
        result.moveCenter(QPoint(self.target.x(), self.height() - 1 - self.target.y()))
        return result

    def game_over(self):
        return self._game_ended

    def is_shooting(self):
        return self._auto_shoot_timer.isActive()


class GameBoard(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("&Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange("ANGLE")
        angle.set_range(5, 70)

        force = LCDRange("FORCE")
        force.set_range(10, 50)

        self._cannon_field = CannonField()

        angle.value_changed.connect(self._cannon_field.set_angle)
        self._cannon_field.angle_changed.connect(angle.set_value)

        force.value_changed.connect(self._cannon_field.set_force)
        self._cannon_field.force_changed.connect(force.set_value)

        self._cannon_field.hit.connect(self.hit)
        self._cannon_field.missed.connect(self.missed)

        shoot = QPushButton("&Shoot")
        shoot.setFont(QFont("Times", 18, QFont.Bold))

        shoot.clicked.connect(self.fire)
        self._cannon_field.can_shoot.connect(shoot.setEnabled)

        restart = QPushButton("&New Game")
        restart.setFont(QFont("Times", 18, QFont.Bold))

        restart.clicked.connect(self.new_game)

        self.hits = QLCDNumber(2)
        self._shots_left = QLCDNumber(2)
        hits_label = QLabel("HITS")
        shots_left_label = QLabel("SHOTS LEFT")

        top_layout = QHBoxLayout()
        top_layout.addWidget(shoot)
        top_layout.addWidget(self.hits)
        top_layout.addWidget(hits_label)
        top_layout.addWidget(self._shots_left)
        top_layout.addWidget(shots_left_label)
        top_layout.addStretch(1)
        top_layout.addWidget(restart)

        left_layout = QVBoxLayout()
        left_layout.addWidget(angle)
        left_layout.addWidget(force)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addLayout(top_layout, 0, 1)
        grid_layout.addLayout(left_layout, 1, 0)
        grid_layout.addWidget(self._cannon_field, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        force.set_value(25)
        angle.setFocus()

        self.new_game()

    @Slot()
    def fire(self):
        if self._cannon_field.game_over() or self._cannon_field.is_shooting():
            return
        self._shots_left.display(self._shots_left.intValue() - 1)
        self._cannon_field.shoot()

    @Slot()
    def hit(self):
        self.hits.display(self.hits.intValue() + 1)
        if self._shots_left.intValue() == 0:
            self._cannon_field.set_game_over()
        else:
            self._cannon_field.new_target()

    @Slot()
    def missed(self):
        if self._shots_left.intValue() == 0:
            self._cannon_field.set_game_over()

    @Slot()
    def new_game(self):
        self._shots_left.display(15)
        self.hits.display(0)
        self._cannon_field.restart_game()
        self._cannon_field.new_target()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    board = GameBoard()
    board.setGeometry(100, 100, 500, 355)
    board.show()
    sys.exit(app.exec())

# PySide6 tutorial 10


import sys

from PySide6.QtCore import QRect, Qt, Signal, Slot
from PySide6.QtGui import QColor, QFont, QPainter, QPalette
from PySide6.QtWidgets import (QApplication, QGridLayout, QLCDNumber,
                               QPushButton, QSlider, QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning(f"LCDRange::setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)


class CannonField(QWidget):

    angle_changed = Signal(int)
    force_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self._current_force = 0
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def force(self):
        return self._current_force

    @Slot(int)
    def set_force(self, force):
        if force < 0:
            force = 0
        if self._current_force == force:
            return
        self._current_force = force
        self.force_changed.emit(self._current_force)

    def paintEvent(self, event):
        painter = QPainter(self)

        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.blue)

        painter.translate(0, self.height())
        painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16)
        painter.rotate(-self._current_angle)
        painter.drawRect(QRect(33, -4, 15, 8))
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()

    def cannon_rect(self):
        result = QRect(0, 0, 50, 50)
        result.moveBottomLeft(self.rect().bottomLect())
        return result


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("&Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange()
        angle.set_range(5, 70)

        force = LCDRange()
        force.set_range(10, 50)

        cannon_field = CannonField()

        angle.value_changed.connect(cannon_field.set_angle)
        cannon_field.angle_changed.connect(angle.set_value)

        force.value_changed.connect(cannon_field.set_force)
        cannon_field.force_changed.connect(force.set_value)

        left_layout = QVBoxLayout()
        left_layout.addWidget(angle)
        left_layout.addWidget(force)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addLayout(left_layout, 1, 0)
        grid_layout.addWidget(cannon_field, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        force.set_value(25)
        angle.setFocus()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.setGeometry(100, 100, 500, 355)
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 7


import sys

from PySide6.QtCore import Signal, Slot, Qt
from PySide6.QtGui import QFont
from PySide6.QtWidgets import (QApplication, QGridLayout, QLCDNumber,
                               QPushButton, QSlider, QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        lcd = QLCDNumber(2)

        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))
        quit.clicked.connect(qApp.quit)

        previous_range = None

        layout = QVBoxLayout(self)
        layout.addWidget(quit)
        grid = QGridLayout()
        layout.addLayout(grid)

        for row in range(3):
            for column in range(3):
                lcd_range = LCDRange()
                grid.addWidget(lcd_range, row, column)

                if previous_range:
                    lcd_range.value_changed.connect(previous_range.set_value)

                previous_range = lcd_range


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 3


import sys

from PySide6.QtGui import QFont
from PySide6.QtWidgets import (QApplication, QPushButton, QWidget)


if __name__ == '__main__':
    app = QApplication(sys.argv)

    window = QWidget()
    window.resize(200, 120)

    quit = QPushButton("Quit", window)
    quit.setFont(QFont("Times", 18, QFont.Bold))
    quit.setGeometry(10, 40, 180, 40)
    quit.clicked.connect(app.quit)

    window.show()
    sys.exit(app.exec())

# PySide6 tutorial 4


import sys

from PySide6.QtGui import QFont
from PySide6.QtWidgets import (QApplication, QPushButton, QWidget)


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        self.setFixedSize(200, 120)

        self.quit = QPushButton("Quit", self)
        self.quit.setGeometry(62, 40, 75, 30)
        self.quit.setFont(QFont("Times", 18, QFont.Bold))

        self.quit.clicked.connect(qApp.quit)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 1


import sys

from PySide6.QtWidgets import QApplication, QPushButton


if __name__ == '__main__':
    app = QApplication(sys.argv)

    hello = QPushButton("Hello world!")
    hello.resize(100, 30)

    hello.show()

    sys.exit(app.exec())

# PySide6 tutorial 12


import sys
import math
import random

from PySide6.QtCore import QPoint, QRect, QTime, QTimer, Qt, Signal, Slot
from PySide6.QtGui import QColor, QFont, QPainter, QPalette, QRegion
from PySide6.QtWidgets import (QApplication, QGridLayout, QHBoxLayout,
                               QLabel, QLCDNumber, QPushButton, QSlider,
                               QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, text=None, parent=None):
        if isinstance(text, QWidget):
            parent = text
            text = None

        super().__init__(parent)

        self.init()

        if text:
            self.set_text(text)

    def init(self):
        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)
        self.label = QLabel()
        self.label.setAlignment(Qt.AlignHCenter | Qt.AlignTop)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)
        layout.addWidget(self.label)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def text(self):
        return self.label.text()

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning(f"LCDRange::setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)

    def set_text(self, text):
        self.label.setText(text)


class CannonField(QWidget):

    angle_changed = Signal(int)
    force_changed = Signal(int)
    hit = Signal()
    missed = Signal()

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self._current_force = 0
        self._timer_count = 0
        self._auto_shoot_timer = QTimer(self)
        self._auto_shoot_timer.timeout.connect(self.move_shot)
        self._shoot_angle = 0
        self._shoot_force = 0
        self.target = QPoint(0, 0)
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)
        self.new_target()

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def force(self):
        return self._current_force

    @Slot(int)
    def set_force(self, force):
        if force < 0:
            force = 0
        if self._current_force == force:
            return
        self._current_force = force
        self.force_changed.emit(self._current_force)

    @Slot()
    def shoot(self):
        if self._auto_shoot_timer.isActive():
            return
        self._timer_count = 0
        self._shoot_angle = self._current_angle
        self._shoot_force = self._current_force
        self._auto_shoot_timer.start(5)

    first_time = True

    def new_target(self):
        if CannonField.first_time:
            CannonField.first_time = False
            midnight = QTime(0, 0, 0)
            random.seed(midnight.secsTo(QTime.currentTime()))

        self.target = QPoint(200 + random.randint(0, 190 - 1), 10 + random.randint(0, 255 - 1))
        self.update()

    @Slot()
    def move_shot(self):
        region = QRegion(self.shot_rect())
        self._timer_count += 1

        shot_r = self.shot_rect()

        if shot_r.intersects(self.target_rect()):
            self._auto_shoot_timer.stop()
            self.hit.emit()
        elif shot_r.x() > self.width() or shot_r.y() > self.height():
            self._auto_shoot_timer.stop()
            self.missed.emit()
        else:
            region = region.united(QRegion(shot_r))

        self.update(region)

    def paintEvent(self, event):
        painter = QPainter(self)

        self.paint_cannon(painter)
        if self._auto_shoot_timer.isActive():
            self.paint_shot(painter)

        self.paint_target(painter)
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()

    def paint_shot(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.black)
        painter.drawRect(self.shot_rect())

    def paint_target(self, painter):
        painter.setPen(Qt.black)
        painter.setBrush(Qt.red)
        painter.drawRect(self.target_rect())

    barrel_rect = QRect(33, -4, 15, 8)

    def paint_cannon(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.blue)

        painter.save()
        painter.translate(0, self.height())
        painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16)
        painter.rotate(-self._current_angle)
        painter.drawRect(CannonField.barrel_rect)
        painter.restore()

    def cannon_rect(self):
        result = QRect(0, 0, 50, 50)
        result.moveBottomLeft(self.rect().bottomLect())
        return result

    def shot_rect(self):
        gravity = 4.0

        time = self._timer_count / 40.0
        velocity = self._shoot_force
        radians = self._shoot_angle * math.pi / 180

        velx = velocity * math.cos(radians)
        vely = velocity * math.sin(radians)
        x0 = (CannonField.barrel_rect.right() + 5) * math.cos(radians)
        y0 = (CannonField.barrel_rect.right() + 5) * math.sin(radians)
        x = x0 + velx * time
        y = y0 + vely * time - 0.5 * gravity * time * time

        result = QRect(0, 0, 6, 6)
        result.moveCenter(QPoint(round(x), self.height() - 1 - round(y)))
        return result

    def target_rect(self):
        result = QRect(0, 0, 20, 10)
        result.moveCenter(QPoint(self.target.x(), self.height() - 1 - self.target.y()))
        return result


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("&Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange("ANGLE")
        angle.set_range(5, 70)

        force = LCDRange("FORCE")
        force.set_range(10, 50)

        cannon_field = CannonField()

        angle.value_changed.connect(cannon_field.set_angle)
        cannon_field.angle_changed.connect(angle.set_value)

        force.value_changed.connect(cannon_field.set_force)
        cannon_field.force_changed.connect(force.set_value)

        shoot = QPushButton("&Shoot")
        shoot.setFont(QFont("Times", 18, QFont.Bold))

        shoot.clicked.connect(cannon_field.shoot)

        top_layout = QHBoxLayout()
        top_layout.addWidget(shoot)
        top_layout.addStretch(1)

        left_layout = QVBoxLayout()
        left_layout.addWidget(angle)
        left_layout.addWidget(force)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addLayout(top_layout, 0, 1)
        grid_layout.addLayout(left_layout, 1, 0)
        grid_layout.addWidget(cannon_field, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        force.set_value(25)
        angle.setFocus()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.setGeometry(100, 100, 500, 355)
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 2


import sys

from PySide6.QtCore import (QPoint, QRect, QTime, QTimer, Qt)
from PySide6.QtGui import QFont
from PySide6.QtWidgets import (QApplication, QPushButton)


if __name__ == '__main__':
    app = QApplication(sys.argv)

    quit = QPushButton("Quit")
    quit.resize(75, 30)
    quit.setFont(QFont("Times", 18, QFont.Bold))

    quit.clicked.connect(app.quit)

    quit.show()
    sys.exit(app.exec())

# PySide6 tutorial 5


import sys

from PySide6.QtCore import Qt
from PySide6.QtGui import QFont
from PySide6.QtWidgets import (QApplication, QLCDNumber, QPushButton,
                               QSlider, QVBoxLayout, QWidget)


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        lcd = QLCDNumber(2)

        slider = QSlider(Qt.Horizontal)
        slider.setRange(0, 99)
        slider.setValue(0)

        quit.clicked.connect(qApp.quit)
        slider.valueChanged.connect(lcd.display)

        layout = QVBoxLayout(self)
        layout.addWidget(quit)
        layout.addWidget(lcd)
        layout.addWidget(slider)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 11


import sys
import math

from PySide6.QtCore import QPoint, QRect, QTimer, Qt, Signal, Slot
from PySide6.QtGui import QColor, QFont, QPainter, QPalette, QRegion
from PySide6.QtWidgets import (QApplication, QGridLayout, QHBoxLayout,
                               QLCDNumber, QPushButton, QSlider,
                               QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning(f"LCDRange::setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)


class CannonField(QWidget):

    angle_changed = Signal(int)
    force_changed = Signal(int)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self._current_force = 0
        self._timer_count = 0
        self._auto_shoot_timer = QTimer(self)
        self._auto_shoot_timer.timeout.connect(self.move_shot)
        self._shoot_angle = 0
        self._shoot_force = 0
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def force(self):
        return self._current_force

    @Slot(int)
    def set_force(self, force):
        if force < 0:
            force = 0
        if self._current_force == force:
            return
        self._current_force = force
        self.force_changed.emit(self._current_force)

    @Slot()
    def shoot(self):
        if self._auto_shoot_timer.isActive():
            return
        self._timer_count = 0
        self._shoot_angle = self._current_angle
        self._shoot_force = self._current_force
        self._auto_shoot_timer.start(5)

    @Slot()
    def move_shot(self):
        region = QRegion(self.shot_rect())
        self._timer_count += 1

        shot_r = self.shot_rect()

        if shot_r.x() > self.width() or shot_r.y() > self.height():
            self._auto_shoot_timer.stop()
        else:
            region = region.united(QRegion(shot_r))

        self.update(region)

    def paintEvent(self, event):
        painter = QPainter(self)

        self.paint_cannon(painter)
        if self._auto_shoot_timer.isActive():
            self.paint_shot(painter)
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()

    def paint_shot(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.black)
        painter.drawRect(self.shot_rect())

    barrel_rect = QRect(33, -4, 15, 8)

    def paint_cannon(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.blue)

        painter.save()
        painter.translate(0, self.height())
        painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16)
        painter.rotate(-self._current_angle)
        painter.drawRect(CannonField.barrel_rect)
        painter.restore()

    def cannon_rect(self):
        result = QRect(0, 0, 50, 50)
        result.moveBottomLeft(self.rect().bottomLect())
        return result

    def shot_rect(self):
        gravity = 4.0

        time = self._timer_count / 40.0
        velocity = self._shoot_force
        radians = self._shoot_angle * math.pi / 180

        velx = velocity * math.cos(radians)
        vely = velocity * math.sin(radians)
        x0 = (CannonField.barrel_rect.right() + 5) * math.cos(radians)
        y0 = (CannonField.barrel_rect.right() + 5) * math.sin(radians)
        x = x0 + velx * time
        y = y0 + vely * time - 0.5 * gravity * time * time

        result = QRect(0, 0, 6, 6)
        result.moveCenter(QPoint(round(x), self.height() - 1 - round(y)))
        return result


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("&Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange()
        angle.set_range(5, 70)

        force = LCDRange()
        force.set_range(10, 50)

        cannon_field = CannonField()

        angle.value_changed.connect(cannon_field.set_angle)
        cannon_field.angle_changed.connect(angle.set_value)

        force.value_changed.connect(cannon_field.set_force)
        cannon_field.force_changed.connect(force.set_value)

        shoot = QPushButton("&Shoot")
        shoot.setFont(QFont("Times", 18, QFont.Bold))

        shoot.clicked.connect(cannon_field.shoot)

        top_layout = QHBoxLayout()
        top_layout.addWidget(shoot)
        top_layout.addStretch(1)

        left_layout = QVBoxLayout()
        left_layout.addWidget(angle)
        left_layout.addWidget(force)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addLayout(top_layout, 0, 1)
        grid_layout.addLayout(left_layout, 1, 0)
        grid_layout.addWidget(cannon_field, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        force.set_value(25)
        angle.setFocus()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.setGeometry(100, 100, 500, 355)
    widget.show()
    sys.exit(app.exec())

# PySide6 tutorial 14


import sys
import math
import random

from PySide6.QtCore import (QPoint, QRect, QTime, QTimer, QSize, Qt, SIGNAL,
                            SLOT, Signal, Slot)
from PySide6.QtGui import (QColor, QFont, QKeySequence, QPainter, QPalette,
                           QShortcut, QRegion)
from PySide6.QtWidgets import (QApplication, QFrame, QGridLayout, QHBoxLayout,
                               QLabel, QLCDNumber, QPushButton, QSizePolicy,
                               QSlider, QVBoxLayout, QWidget)


class LCDRange(QWidget):

    value_changed = Signal(int)

    def __init__(self, text=None, parent=None):
        if isinstance(text, QWidget):
            parent = text
            text = None

        super().__init__(parent)

        self.init()

        if text:
            self.set_text(text)

    def init(self):
        lcd = QLCDNumber(2)
        self.slider = QSlider(Qt.Horizontal)
        self.slider.setRange(0, 99)
        self.slider.setValue(0)
        self.label = QLabel()
        self.label.setAlignment(Qt.AlignHCenter | Qt.AlignTop)
        self.label.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Fixed)

        self.slider.valueChanged.connect(lcd.display)
        self.slider.valueChanged.connect(self.value_changed)

        layout = QVBoxLayout(self)
        layout.addWidget(lcd)
        layout.addWidget(self.slider)
        layout.addWidget(self.label)

        self.setFocusProxy(self.slider)

    def value(self):
        return self.slider.value()

    @Slot(int)
    def set_value(self, value):
        self.slider.setValue(value)

    def text(self):
        return self.label.text()

    def set_range(self, minValue, maxValue):
        if minValue < 0 or maxValue > 99 or minValue > maxValue:
            qWarning(f"LCDRange::setRange({minValue}, {maxValue})\n"
                    "\tRange must be 0..99\n"
                    "\tand minValue must not be greater than maxValue")
            return

        self.slider.setRange(minValue, maxValue)

    def set_text(self, text):
        self.label.setText(text)


class CannonField(QWidget):

    angle_changed = Signal(int)
    force_changed = Signal(int)
    hit = Signal()
    missed = Signal()
    can_shoot = Signal(bool)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._current_angle = 45
        self._current_force = 0
        self._timer_count = 0
        self._auto_shoot_timer = QTimer(self)
        self._auto_shoot_timer.timeout.connect(self.move_shot)
        self._shoot_angle = 0
        self._shoot_force = 0
        self.target = QPoint(0, 0)
        self._game_ended = False
        self._barrel_pressed = False
        self.setPalette(QPalette(QColor(250, 250, 200)))
        self.setAutoFillBackground(True)
        self.new_target()

    def angle(self):
        return self._current_angle

    @Slot(int)
    def set_angle(self, angle):
        if angle < 5:
            angle = 5
        if angle > 70:
            angle = 70
        if self._current_angle == angle:
            return
        self._current_angle = angle
        self.update()
        self.angle_changed.emit(self._current_angle)

    def force(self):
        return self._current_force

    @Slot(int)
    def set_force(self, force):
        if force < 0:
            force = 0
        if self._current_force == force:
            return
        self._current_force = force
        self.force_changed.emit(self._current_force)

    @Slot()
    def shoot(self):
        if self.is_shooting():
            return
        self._timer_count = 0
        self._shoot_angle = self._current_angle
        self._shoot_force = self._current_force
        self._auto_shoot_timer.start(5)
        self.can_shoot.emit(False)

    first_time = True

    def new_target(self):
        if CannonField.first_time:
            CannonField.first_time = False
            midnight = QTime(0, 0, 0)
            random.seed(midnight.secsTo(QTime.currentTime()))

        self.target = QPoint(200 + random.randint(0, 190 - 1), 10 + random.randint(0, 255 - 1))
        self.update()

    def set_game_over(self):
        if self._game_ended:
            return
        if self.is_shooting():
            self._auto_shoot_timer.stop()
        self._game_ended = True
        self.update()

    def restart_game(self):
        if self.is_shooting():
            self._auto_shoot_timer.stop()
        self._game_ended = False
        self.update()
        self.can_shoot.emit(True)

    @Slot()
    def move_shot(self):
        region = QRegion(self.shot_rect())
        self._timer_count += 1

        shot_r = self.shot_rect()

        if shot_r.intersects(self.target_rect()):
            self._auto_shoot_timer.stop()
            self.hit.emit()
            self.can_shoot.emit(True)
        elif shot_r.x() > self.width() or shot_r.y() > self.height() or shot_r.intersects(self.barrier_rect()):
            self._auto_shoot_timer.stop()
            self.missed.emit()
            self.can_shoot.emit(True)
        else:
            region = region.united(QRegion(shot_r))

        self.update(region)

    def mousePressEvent(self, event):
        if event.button() != Qt.LeftButton:
            return
        if self.barrel_hit(event.position().toPoint()):
            self._barrel_pressed = True

    def mouseMoveEvent(self, event):
        if not self._barrel_pressed:
            return
        pos = event.position().toPoint()
        if pos.x() <= 0:
            pos.setX(1)
        if pos.y() >= self.height():
            pos.setY(self.height() - 1)
        rad = math.atan((float(self.rect().bottom()) - pos.y()) / pos.x())
        self.set_angle(round(rad * 180 / math.pi))

    def mouseReleaseEvent(self, event):
        if event.button() == Qt.LeftButton:
            self._barrel_pressed = False

    def paintEvent(self, event):
        painter = QPainter(self)

        if self._game_ended:
            painter.setPen(Qt.black)
            painter.setFont(QFont("Courier", 48, QFont.Bold))
            painter.drawText(self.rect(), Qt.AlignCenter, "Game Over")

        self.paint_cannon(painter)
        self.paint_barrier(painter)
        if self.is_shooting():
            self.paint_shot(painter)
        if not self._game_ended:
            self.paint_target(painter)
        # QPainter needs an explicit end() in PyPy. This will become a context manager in 6.3.
        painter.end()

    def paint_shot(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.black)
        painter.drawRect(self.shot_rect())

    def paint_target(self, painter):
        painter.setPen(Qt.black)
        painter.setBrush(Qt.red)
        painter.drawRect(self.target_rect())

    def paint_barrier(self, painter):
        painter.setPen(Qt.black)
        painter.setBrush(Qt.yellow)
        painter.drawRect(self.barrier_rect())

    barrel_rect = QRect(33, -4, 15, 8)

    def paint_cannon(self, painter):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.blue)

        painter.save()
        painter.translate(0, self.height())
        painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16)
        painter.rotate(-self._current_angle)
        painter.drawRect(CannonField.barrel_rect)
        painter.restore()

    def cannon_rect(self):
        result = QRect(0, 0, 50, 50)
        result.moveBottomLeft(self.rect().bottomLect())
        return result

    def shot_rect(self):
        gravity = 4.0

        time = self._timer_count / 40.0
        velocity = self._shoot_force
        radians = self._shoot_angle * math.pi / 180

        velx = velocity * math.cos(radians)
        vely = velocity * math.sin(radians)
        x0 = (CannonField.barrel_rect.right() + 5) * math.cos(radians)
        y0 = (CannonField.barrel_rect.right() + 5) * math.sin(radians)
        x = x0 + velx * time
        y = y0 + vely * time - 0.5 * gravity * time * time

        result = QRect(0, 0, 6, 6)
        result.moveCenter(QPoint(round(x), self.height() - 1 - round(y)))
        return result

    def target_rect(self):
        result = QRect(0, 0, 20, 10)
        result.moveCenter(QPoint(self.target.x(), self.height() - 1 - self.target.y()))
        return result

    def barrier_rect(self):
        return QRect(145, self.height() - 100, 15, 99)

    def barrel_hit(self, pos):
        matrix = QTransform()
        matrix.translate(0, self.height())
        matrix.rotate(-self._current_angle)
        matrix, invertible = matrix.inverted()
        return self.barrel_rect.contains(matrix.map(pos))

    def game_over(self):
        return self._game_ended

    def is_shooting(self):
        return self._auto_shoot_timer.isActive()

    def sizeHint(self):
        return QSize(400, 300)


class GameBoard(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)

        quit = QPushButton("&Quit")
        quit.setFont(QFont("Times", 18, QFont.Bold))

        quit.clicked.connect(qApp.quit)

        angle = LCDRange("ANGLE")
        angle.set_range(5, 70)

        force = LCDRange("FORCE")
        force.set_range(10, 50)

        cannon_box = QFrame()
        cannon_box.setFrameStyle(QFrame.WinPanel | QFrame.Sunken)

        self._cannon_field = CannonField()

        angle.value_changed.connect(self._cannon_field.set_angle)
        self._cannon_field.angle_changed.connect(angle.set_value)

        force.value_changed.connect(self._cannon_field.set_force)
        self._cannon_field.force_changed.connect(force.set_value)

        self._cannon_field.hit.connect(self.hit)
        self._cannon_field.missed.connect(self.missed)

        shoot = QPushButton("&Shoot")
        shoot.setFont(QFont("Times", 18, QFont.Bold))

        shoot.clicked.connect(self.fire)
        self._cannon_field.can_shoot.connect(shoot.setEnabled)

        restart = QPushButton("&New Game")
        restart.setFont(QFont("Times", 18, QFont.Bold))

        restart.clicked.connect(self.new_game)

        self.hits = QLCDNumber(2)
        self._shots_left = QLCDNumber(2)
        hits_label = QLabel("HITS")
        shots_left_label = QLabel("SHOTS LEFT")

        QShortcut(QKeySequence(Qt.Key_Enter), self, self.fire)
        QShortcut(QKeySequence(Qt.Key_Return), self, self.fire)
        QShortcut(QKeySequence(Qt.CTRL + Qt.Key_Q), self, self.close)

        top_layout = QHBoxLayout()
        top_layout.addWidget(shoot)
        top_layout.addWidget(self.hits)
        top_layout.addWidget(hits_label)
        top_layout.addWidget(self._shots_left)
        top_layout.addWidget(shots_left_label)
        top_layout.addStretch(1)
        top_layout.addWidget(restart)

        left_layout = QVBoxLayout()
        left_layout.addWidget(angle)
        left_layout.addWidget(force)

        cannon_layout = QVBoxLayout()
        cannon_layout.addWidget(self._cannon_field)
        cannon_box.setLayout(cannon_layout)

        grid_layout = QGridLayout(self)
        grid_layout.addWidget(quit, 0, 0)
        grid_layout.addLayout(top_layout, 0, 1)
        grid_layout.addLayout(left_layout, 1, 0)
        grid_layout.addWidget(cannon_box, 1, 1, 2, 1)
        grid_layout.setColumnStretch(1, 10)

        angle.set_value(60)
        force.set_value(25)
        angle.setFocus()

        self.new_game()

    @Slot()
    def fire(self):
        if self._cannon_field.game_over() or self._cannon_field.is_shooting():
            return
        self._shots_left.display(self._shots_left.intValue() - 1)
        self._cannon_field.shoot()

    @Slot()
    def hit(self):
        self.hits.display(self.hits.intValue() + 1)
        if self._shots_left.intValue() == 0:
            self._cannon_field.set_game_over()
        else:
            self._cannon_field.new_target()

    @Slot()
    def missed(self):
        if self._shots_left.intValue() == 0:
            self._cannon_field.set_game_over()

    @Slot()
    def new_game(self):
        self._shots_left.display(15)
        self.hits.display(0)
        self._cannon_field.restart_game()
        self._cannon_field.new_target()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    board = GameBoard()
    board.setGeometry(100, 100, 500, 355)
    board.show()
    sys.exit(app.exec())