强制QGraphicsItem要留 [英] Forcing QGraphicsItem To Stay Put

问题描述

我有一个 QGraphicsScene 充满 QGraphicsItems ，用户可以平移和缩放检查所有的 QGraphicsItems 。但是，我想有一个 QGraphicsTextItem 标签，总是保持在屏幕的左上角。忽略缩放很容易，因为我可以只是 setFlags（QGraphicsItem :: ItemIgnoresTransformations），但我还没有想出如何强制位置保持在顶部 - 剩下。

I have a QGraphicsScene that is filled with QGraphicsItems, and the user is able to pan and zoom around to inspect all of the various QGraphicsItems. However, I would like to have a QGraphicsTextItem label that always stays put at the top left of the screen. Ignoring the zooms is easy, as I can just setFlags(QGraphicsItem::ItemIgnoresTransformations), but I've yet to figure out how to force the position to stay at the top-left. What's the best way to make my label "float" in the same place?

推荐答案

也许你只想放一个普通的 QLabel 直接在视图上，而不是试图使一部分场景留在一个地方，如此问题。

Perhaps you just want to put a regular QLabel right on the view instead of trying to make a part of the scene stay in one place as discussed in this question.

注意： / strong>正如在另一个答案中提到的，这个技巧通常不会与硬件加速视图一起使用。在这些情况下，您需要将文本项目作为场景的一部分。

Note: As mentioned in another answer, this trick will often not work with hardware accelerated views. In these cases, you will need to make the text items a part of the scene.

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