We know that the UI thread of android is the main thread of android, and the main thread is thread-safe. Some time-consuming threads, such as downloading, uploading or parsing large files, cannot be placed in the main thread. Why do you say this? Because the time-consuming operation in the main thread will cause the interface to get stuck, resulting in ANR (application unresponsive), ANR gives the customer a very bad experience, and as a programmer, try to avoid this situation. How do we do it? In fact, we can use multi-threading to solve. For example, we can start a new thread to do this time-consuming operation without affecting the interface loading of the main thread. Here is an example to illustrate:
public class HandlerTest extends Activity{
private Handler handler;
private Runnable runnable = new Runnable {
public void run{
initViews(); //Big data loading
}
}
public void onCreate(){
super.savedInstance (....);
handler = new Handler ();
// initViews(); easy to get stuck if loaded like this
//We use another method to achieve
handler.postDelayed(runnable,1000); Open another thread to load data
}
public void initViews(){
.......
.......
...... //load a lot of data
}
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The above multi-threaded method can avoid causing ANR and can also achieve fast loading!