Synchronous, callback, asynchronous, thread

Synchronization:

Callback:

Asynchronous:

 

Thread
Although you can put your applicationProgramRestricted to a single process, sometimes you still need to derive a thread to process Background tasks.
Because the user interface must respond to user operations in a very timely manner, the thread controlling the activity should not be used to process
Network downloads and other time-consuming operations. All tasks that cannot be completed instantly should be arranged in different threads.
Thread inCodeIs created with a standard Java thread object. Android provides many classes to facilitate thread management: Logoff
To run a message loop in a thread, handler is used to process messages, and handlerthread is used to use a message loop
Enable a thread.