我使用了这个解决方案，我认为它比onWindowFocusChanged()更好。如果你打开一个对话片段，然后旋转电话，onWindowFocusChanged将被调用只有当用户关闭对话框):

    yourView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

        @Override
        public void onGlobalLayout() {
            // Ensure you call it only once :
            yourView.getViewTreeObserver().removeGlobalOnLayoutListener(this);

            // Here you can get the size :)
        }
    });

编辑:由于removeGlobalOnLayoutListener已弃用，你现在应该做:

@SuppressLint("NewApi")
@SuppressWarnings("deprecation")
@Override
public void onGlobalLayout() {

    // Ensure you call it only once :
    if(android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.JELLY_BEAN) {
        yourView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
    }
    else {
        yourView.getViewTreeObserver().removeGlobalOnLayoutListener(this);
    }

    // Here you can get the size :)
}

如果你使用RxJava & RxBindings，一行。类似的方法没有样板。这也解决了蒂姆·奥廷(Tim Autin)的回答中隐藏警告的问题。

RxView.layoutChanges(yourView).take(1)
      .subscribe(aVoid -> {
           // width and height have been calculated here
      });

就是它了。不需要取消订阅，即使从未调用。

带post的答案是不正确的，因为大小可能无法重新计算。 另一个重要的事情是视图和所有它的祖先必须是可见的。为此，我使用属性view . isshows。

下面是我的kotlin函数，它可以放在utils中的某个地方:

fun View.onInitialized(onInit: () -> Unit) {
    viewTreeObserver.addOnGlobalLayoutListener(object : OnGlobalLayoutListener {
        override fun onGlobalLayout() {
            if (isShown) {
                viewTreeObserver.removeOnGlobalLayoutListener(this)
                onInit()
            }
        }
    })
}

用法是:

myView.onInitialized {
    Log.d(TAG, "width is: " + myView.width)
}

你调用getWidth()太早了。UI还没有在屏幕上调整大小和布局。

无论如何，我怀疑您是否想要做您正在做的事情——动画小部件不会改变它们的可点击区域，因此无论它如何旋转，按钮仍然会对原始方向的点击做出响应。

也就是说，您可以使用维度资源来定义按钮大小，然后从布局文件和源代码中引用该维度资源，以避免此问题。

正如Ian在这篇Android开发者文章中所述:

Anyhow, the deal is that layout of the contents of a window happens after all the elements are constructed and added to their parent views. It has to be this way, because until you know what components a View contains, and what they contain, and so on, there's no sensible way you can lay it out. Bottom line, if you call getWidth() etc. in a constructor, it will return zero. The procedure is to create all your view elements in the constructor, then wait for your View's onSizeChanged() method to be called -- that's when you first find out your real size, so that's when you set up the sizes of your GUI elements. Be aware too that onSizeChanged() is sometimes called with parameters of zero -- check for this case, and return immediately (so you don't get a divide by zero when calculating your layout, etc.). Some time later it will be called with the real values.

我们可以用

@Override
 public void onWindowFocusChanged(boolean hasFocus) {
  super.onWindowFocusChanged(hasFocus);
  //Here you can get the size!
 }