2017-03-06 58 views
0

我想通知UI線程有關從屬線程發生更改事件,以便UI線程可以更新視圖。對於一個執行確實幹得不錯,如:如何讓奴隸通知主人?

public Class MainActivity extends Activity{ 

private final Object mutex = new Object(); 
private String[] data; 
private boolean flag = false; 


      //UI Thread 
      synchronized(mutex) 
      { 
       try { 
        mutex.wait();      
        if(!flag){ 
         adapter = new PlayListAdapter(this, R.layout.activity_row_item, data);    
         listView = (ListView)findViewById(R.id.playlist_listView);   
         listView.setAdapter(adapter); 
         flag=true; 
        } else { 
         adapter.clear(); 
         adapter.addAll(data); 
         adapter.notifyDataSetChanged(); 
        } 
       } catch (InterruptedException e) { 
        e.printStackTrace(); 
       } 
      }  

      //Slave thread 
      While(true){ 
       //Waiting for an event to occur in order to update data 
       //change data 
       synchronized(mutex){ 
         mutex.notify(); 
       } 
      } 
    } 

但是當我試圖讓UI線程無限循環,等待從機的通知,該方案沒有奏效:

//UI Thread 
    while(true){ 
      synchronized(mutex) 
      { 
       try { 
        mutex.wait();      
        if(!flag){ 
         adapter = new PlayListAdapter(this, R.layout.activity_row_item, data);    
         listView = (ListView)findViewById(R.id.playlist_listView);   
         listView.setAdapter(adapter); 
         flag=true; 
        } else { 
         adapter.clear(); 
         adapter.addAll(data); 
         adapter.notifyDataSetChanged(); 
        } 
       } catch (InterruptedException e) { 
        e.printStackTrace(); 
       } 
      } 
    }  

我試着首先要改變從奴隸線程的視圖,並發現這是禁止在Android中,所以我試圖然後使用處理程序線程,但事情並沒有順利,因爲我的預期。

回答