ZoomableGraphicView.py 文件源码

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

        self.context_menu_position = None  # type: QPoint
        self.scene_type = 0

        self.zoom_in_action = QAction(self.tr("Zoom in"), self)
        self.zoom_in_action.setShortcut(QKeySequence.ZoomIn)
        self.zoom_in_action.triggered.connect(self.on_zoom_in_action_triggered)
        self.zoom_in_action.setShortcutContext(Qt.WidgetWithChildrenShortcut)
        self.zoom_in_action.setIcon(QIcon.fromTheme("zoom-in"))
        self.addAction(self.zoom_in_action)

        self.zoom_out_action = QAction(self.tr("Zoom out"), self)
        self.zoom_out_action.setShortcut(QKeySequence.ZoomOut)
        self.zoom_out_action.triggered.connect(self.on_zoom_out_action_triggered)
        self.zoom_out_action.setShortcutContext(Qt.WidgetWithChildrenShortcut)
        self.zoom_out_action.setIcon(QIcon.fromTheme("zoom-out"))
        self.addAction(self.zoom_out_action)

        self.zoom_original_action = QAction(self.tr("Zoom original"), self)
        self.zoom_original_action.setShortcut(QKeySequence(Qt.CTRL + Qt.Key_0))
        self.zoom_original_action.triggered.connect(self.on_zoom_original_action_triggered)
        self.zoom_original_action.setShortcutContext(Qt.WidgetWithChildrenShortcut)
        self.zoom_original_action.setIcon(QIcon.fromTheme("zoom-original"))
        self.addAction(self.zoom_original_action)

        self.redraw_timer = QTimer()
        self.redraw_timer.setSingleShot(True)
        self.redraw_timer.timeout.connect(self.redraw_view)

        self.zoomed.connect(self.on_signal_zoomed)

        self.scene_y_min = float("nan")  # NaN = AutoDetect
        self.scene_y_max = float("nan")  # NaN = AutoDetect

        self.scene_x_zoom_stretch = 1