GTK：在scrolled_window滚动后获取滚动事件上的指针位置
我在滚动窗口内有一个绘图区域（带有方便的视口）， 并且该绘图区域会根据传入的运动通知事件进行自我更新。 当我滚动该区域时，虽然显然没有发出任何运动事件， 但我想解决这个问题，所以尝试连接绘图区域 “滚动事件”信号发送至相同的运动通知回调。
我在这里面临的问题是这个信号是在滚动窗口之前发出的 已更新其视口，因此在回调中，我最终得到了在滚动之前为 true 的指针坐标，使其看起来在滚动时绘图区域始终“落后于实际指针一步”，而不移动指针本身。 我以为我可以通过使用 gdk_window_get_pointer 手动提取坐标来弥补这一点，但后来我意识到这不起作用，因为当回调开始时，指针在技术上仍处于其旧位置。 我还尝试使用 g_signal_connect_after 希望它能在视口滚动后调用回调，但它没有帮助。
我最后的希望是在滚动事件上启动一个计时器，并在最短的时间后触发回调，但这听起来真的很难看，我想不惜一切代价避免这种情况。
关于如何实现这一点有什么想法吗？ 提前致谢！
I've got a drawing area inside a scrolled window (with convenience viewport),
and this drawing area updates itself according to incoming motion-notify-events.
When I scroll the area though obviously no motion events are emitted,
but I wanted to work around this, and so tried to connect the drawing area's
"scroll-event" signal to the same motion-notify callback.
The problem I'm facing here is that this signal is emitted before the scrolled window
has update its viewport, so in the callback, I end up with pointer coordinates that were true just before scrolling, making it look like the drawing area is always "lagging a step behind" the actual pointer when scrolling while not moving the pointer itself.
I thought I could compensate for this by manually extracting the coordinates with gdk_window_get_pointer, but then I realized this cannot work as the pointer is technically still at its old position when the callback is commencing.
I also tried using g_signal_connect_after in hopes it would have the callback get called after the viewport was scrolled, but it didn't help.
My last hope would be to start a timer on scroll-events, and have the callback fire after a minimal amount of time, but this sounds realllly ugly, and I'd like to avoid that at any cost.
Any ideas as to how this could be realized?
Thanks in advance!
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解决方案是连接到 "value-changed " GtkScrolledWindow 信号
调整。
来源： https://mail.gnome.org /archives/gtk-app-devel-list/2011-September/msg00014.html
A solution would be to connect to the "value-changed" signal of the GtkScrolledWindow
adjustments.
Source: https://mail.gnome.org/archives/gtk-app-devel-list/2011-September/msg00014.html