Question

我有两项活动（Activity1和Activity2）和一项AsyncTask（AsyncTask1）

Activity1有一个按钮，点按即可控制Activity2，Activity2有一个AsyncTask，而该任务的onPostExecute()我想要处理{ {1}}中的{1}}。

示例：

活性1

TextView

活性2

Activity1

AsyncTask1

public class Activity1 extends RoboSherlockActivity {
  @Inject (R.id.name) EditText name;
  @Inject (R.id.mybutton) Button button;

  public void onCreate (Bundle savedInstanceState) {
   ...
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent activity2 = new Intent(context, Activity2.class);
                startActivity(activity2);
            }
        });
   ....
  }
}

问题

如何在AsyncTask的public class Activity2 extends RoboSherlockActivity { @InjectView (R.id.name) EditText secret; .... public boolean onCreateOptionsMenu(Menu menu) { menu.add("Save") return true; } ... @Override public boolean onOptionsItemSelected(MenuItem menuItem) { if (menuItem.getTitle().toString().equalsIgnoreCase("Save")) { new AsyncTask1(this, secret.getText().toString()).execute(); } return true; } }中设置名称？

Answer 1

Activity2有一个AsyncTask，在那个任务中我想要onPostExecute（）处理Activity1中的TextView。

不，你不能。您可以在Activtiy1中使用startActivtiyForResult并更新textview

在Activity1中

  Intent intent=new Intent(Activity.this,Activity2.class);  
  startActivityForResult(intent, 2);

然后

   @Override  
   protected void onActivityResult(int requestCode, int resultCode, Intent data)  
   {  
             super.onActivityResult(requestCode, resultCode, data);  

              // check if the request code is same as what is passed  here it is 2  
               if(requestCode==2)  
                     {  
                        String message=data.getStringExtra("key");   
                        textView1.setText(message);  

                     }  

 }

在Activity2中

 Intent intent;
   @Override
   protected void onCreate(Bundle savedInstanceState)
   super.onCreate(savedInstanceState);
   setContentView(R.layout.second);
   intent = getIntent();
   ...// rest of the code
 }

在onSuccess

 protected void onSuccess(String result) {
   intent.putExtra("key",value);  
   setResult(2,intent);  
   activity.finish();
 }

Answer 2

试试这个......

在Activity1中创建一个sharedPreference，从asynctask store中获取成功结果在sharedPreference＆amp;完成活动。

在Activity1的onResume中，从sharedPreference＆amp;获取值。如果它不为null，则设置为Textview ..

Answer 3

我会尝试另一种方法。我不会尝试从AsyncTask更改活动1的元素，而是将AsynTask中的意图发送到活动1。

protected void onSuccess(String result) {
 activity.finish();
 Intent intent = new Intent("MY_CUSTOM_INTENT");
 activity.sendBroadcast(intent);

}

在活动中

  @Override
  public void onResume(){
    super.onResume();
    LocalBroadcastManager.getInstance(this).registerReceiver(myHandler, new IntentFilter("MY_CUSTOM_INTENT");
  }
 BroadcastReceiver myHandler= new BroadcastReceiver() {
     @Override
     public void onReceive(Context context, Intent intent) {
          //CHANGE HERE THE TEXTVIEW
     }
 };

Answer 4

您可以使用静态变量来执行此操作：

public class Activity1 extends RoboSherlockActivity {
  ...

  public static Activity1 instance = null;

  public EditText getName(){
      return name;
  }

  public void onCreate (Bundle savedInstanceState) {
   ...
   instance = this;
   ....
  }

  public void onDestroy(){
    instance = null;
  }
}

并调用此方法：

protected void onSuccess(String result) {
 activity.finis();
 Activity1.instance.getName.setText(result);
 //HERE I WANT TO SET THE NAME: name.setText(result); //How can I do this??
}

如何从AsyncTask管理活动

4 个答案: