What will happen if send message to handler whose activity has been unvisible?

Question

我在activity onCreate方法中创建了一个处理程序，并启动一个后台线程。在后台线程中，我将调用处理程序的sendMessage方法（在处理程序的handleMessage方法中，我更新了活动的UI），但是活动可能是不可见的，会是什么发生？

Answer 1

If you don't do anything UI-related in that handler, it'll execute fine. Keep in mind that holding references to inactive Activity could create a memory leak - you'll prevent the VM from collecting unused resources.