Android BroadcastReceiver onReceive在MainActivity中更新TextView

Question

在MainActivity中，我有一个TextView：textV1。我在MainActivity中也有一个更新该textview的方法：

public void updateTheTextView(final String t) {
    MainActivity.this.runOnUiThread(new Runnable() {
        public void run() {
            TextView textV1 = (TextView) findViewById(R.id.textV1);
            textV1.setText(t);
        }
    });
}

在BroadcasrReceiver中，我需要在MainActivity中更新textV1中的文本。

public class NotifAlarm extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
            // other things done here like notification

            // NEED TO UPDATE TEXTV1 IN MAINACTIVITY HERE
    }
}

如何才能做到这一点？BroadcastReceiver从服务运行。我无法更改此代码。我可以从onReceive（）访问和更改MainActivity中的textV1吗？我尝试了很多事情，但都失败了。

Answer 1

在您的MainActivity初始化MainActivity类变量如下。

public class MainActivity extends Activity {
    private static MainActivity ins;
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ins = this;     
    }

    public static MainActivity  getInstace(){
        return ins;
    }

    public void updateTheTextView(final String t) {
        MainActivity.this.runOnUiThread(new Runnable() {
            public void run() {
                TextView textV1 = (TextView) findViewById(R.id.textV1);
                textV1.setText(t);
            }
        });
    }
}


public class NotifAlarm extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        try {
            MainActivity  .getInstace().updateTheTextView("String");
        } catch (Exception e) {

        }           
    }
}