/**
* Runs the specified action on the UI thread. If the current thread is the UI
* thread, then the action is executed immediately. If the current thread is
* not the UI thread, the action is posted to the event queue of the UI thread.
*
* @param action the action to run on the UI thread
*/
public final void runOnUiThread(Runnable action) {
if (Thread.
currentThread() !=
mUiThread) {
mHandler.post(action);
}
else {
action.run();
}
}
在非ui thread中想要更新ui操作，需要使用runOnUiThread来完成。若当前线程是ui thread则立即执行，否则action 会被post到ui thread的event queue中。
