android - Handler与runOnUiThread更新UI的区别

Question

Handler与runOnUiThread更新UI有什么区别？
分别更适合在哪种情况下用？

Answer 1

In terms of implementation principles, there is no difference between the two. runOnUiThread也是借助Handler实现的。
对于使用场景，runOnUiThread用法简单，并且共享了同一个Handler，用起来高效、方便。另外，如果在主线程中直接调用，runOnUiThread也可以判断并立即执行，不再推入消息队列。
而Handler由于更加基础，所以可定制性要比runOnUiThreadStronger, it can implement functions such as marking and delay, and can be pushed into other message loop threads instead of the main thread.

Answer 2

runOnUiThread directly encapsulates a Runnable object into a Message and hands it to the Looper of the main thread for execution. The execution code is:

handler.post(mRunnable);

If Handler wants to get the same effect, first the Looper bound by Handler must be the Looper of the main thread, which can be obtained through Looper.getMainLooper(). Then also send a runable object through post.

There is essentially no difference.