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.
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.
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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.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:
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.