how to pan images in QGraphicsView(如何在 QGraphicsView 中平移图像)
问题描述
我目前能够将我的图像加载到 Graphics 场景中,然后再次加载到 QGraphicsViewer 中.
I am currently able to load my image into a grahpics scene, and then again into a QGraphicsViewer.
我可以通过检测 QEvent::Wheel 然后调用 graphicsViews 的 scale() 函数来实现缩放功能.
I am able to implement a zoom feature by dtecting a QEvent::Wheel and then calling the graphicsViews's scale() function.
但是,我似乎无法弄清楚如何使平移功能正常工作.我基本上想检测鼠标何时点击了图像,然后随着鼠标向左、向右、向上或向下移动图像.
However, I can't seem to figure out how to get the pan functionality working. I basically want to detect when a mouse has clicked down on the image, and then move the image left, right, up or down along with the mouse.
截至目前,我基本上有一个 MouseFilter 类,用于检测事件,并根据事件类型做不同的事情.我将该侦听器附加到 QGraphicsView 对象
As of right now, I basically have a MouseFilter class that is detecting events, and doing different things depending on the event type. I attached that listener to the QGraphicsView object
推荐答案
QGraphicsView 具有内置的鼠标平移支持.设置正确的 DragMode 它将处理其余的.您确实需要启用滚动条才能工作.
QGraphicsView has build-in mouse-panning support. Set correct DragMode and it will handle the rest. You do need the enable scroll bars for that to work.
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本文标题为:如何在 QGraphicsView 中平移图像


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