QGraphicsScene、QGraphicsItem与QGraphicsView绘制标尺
时间: 2024-04-29 12:16:25 浏览: 17
QGraphicsScene、QGraphicsItem和QGraphicsView可以用来绘制标尺。下面是一个示例代码,演示了如何使用这些类来实现标尺的绘制[^1]:
```python
from PyQt5.QtWidgets import QGraphicsScene, QGraphicsView, QGraphicsLineItem, QApplication
from PyQt5.QtCore import Qt, QPointF
class RulerScene(QGraphicsScene):
def __init__(self, parent=None):
super().__init__(parent)
self.setSceneRect(0, 0, 500, 100)
# 绘制水平标尺
for i in range(0, 501, 50):
line = QGraphicsLineItem(i, 0, i, 10)
self.addItem(line)
text = self.addText(str(i))
text.setPos(i - text.boundingRect().width() / 2, 15)
# 绘制垂直标尺
for i in range(0, 101, 10):
line = QGraphicsLineItem(0, i, 10, i)
self.addItem(line)
text = self.addText(str(i))
text.setPos(15, i - text.boundingRect().height() / 2)
class RulerView(QGraphicsView):
def __init__(self, parent=None):
super().__init__(parent)
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setRenderHint(QPainter.Antialiasing)
self.setDragMode(QGraphicsView.ScrollHandDrag)
self.setTransformationAnchor(QGraphicsView.AnchorUnderMouse)
self.setResizeAnchor(QGraphicsView.AnchorUnderMouse)
self.setInteractive(True)
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
scene = RulerScene()
view = RulerView(scene)
view.show()
sys.exit(app.exec_())
```
这段代码创建了一个自定义的QGraphicsScene子类RulerScene,用于绘制标尺。在RulerScene的构造函数中,我们设置了场景的大小,并使用QGraphicsLineItem和QGraphicsTextItem来绘制水平和垂直的标尺线和标签。然后,我们创建了一个自定义的QGraphicsView子类RulerView,用于显示场景。在RulerView的构造函数中,我们设置了一些视图的属性,例如滚动条策略、渲染提示、拖动模式等。最后,我们创建了一个QApplication实例,将RulerScene和RulerView关联起来,并显示出来。