作用都是重繪界面
貼上源碼
invalidate()
在UI線程調(diào)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線程調(diào)用芬为， 查看源碼會發(fā)現(xiàn)煤禽， 底層也是通過調(diào)用invalidate()方法來實現(xiàn)重繪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);
}
