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copied!<p>The reason you're getting a size of 0 is that the layout isn't finished until after the activity is fully created, i.e. onCreate(), onStart() and onResume() have all gone through. The easiest way I know of to get the exact size is to call your method after the layout has finished, such as by using a click listener on a button. Since the button isn't displayed until the layout is finished, the size must be available by the time its click listener is fired.</p> <p>This is only a guess, but I imagine that this is difficult to do precisely because they don't want people messing with layout sizes once the system has just finished laying out the screen. If they provided a "onLayoutFinished()" callback, then you could get yourself stuck in a loop if you modified the layout in that. For example, imagine: layout is completed; onLayoutFinished() called and you modify the layout in there; the existing layout is now invalid; layout re-done; onLayoutFinished() called again; your code gets called again - and so forth.</p> <p>Another way to do it is to make a custom View and override the <code>onMeasure(int, int)</code> method. The system triggers that method to get the size of each View; if you use something like my example below, you can get the <em>suggested</em> size before the layout is finished:</p> <pre><code>@Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec){ super.onMeasure(widthMeasureSpec, heightMeasureSpec); //getMeasuredHeight() and getMeasuredWidth() now contain the suggested size } </code></pre> <p>(I wrote that it's the suggested size because I think it's possible for the size to be changed after this based on layout constraints. However, that's a vague memory of something I read a while ago, and I never experimented in detail.) Once you've done that, you can use the size for whatever it is you wanted to do - you can even change the size it will use by using <code>setMeasuredDimension(newX, newY)</code>.</p>

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