作用都是重绘界面
贴上源码
invalidate()
在UI线程调用
/**
* Invalidate the whole view. If the view is visible,
* {@link #onDraw(android.graphics.Canvas)} will be called at some point in
* the future.
* <p>
* This must be called from a UI thread. To call from a non-UI thread, call
* {@link #postInvalidate()}.
*/
public void invalidate() {
invalidate(true);
}
postInvalidate()
在非UI线程调用， 查看源码会发现， 底层也是通过调用invalidate()方法来实现重绘UI的
/**
* <p>Cause an invalidate to happen on a subsequent cycle through the event loop.
* Use this to invalidate the View from a non-UI thread.</p>
*
* <p>This method can be invoked from outside of the UI thread
* only when this View is attached to a window.</p>
*
* @see #invalidate()
* @see #postInvalidateDelayed(long)
*/
public void postInvalidate() {
postInvalidateDelayed(0);
}
