问题描述

如何从TabHost中引用一个子activity来调用一个公共函数？

在TabHost中有两个子activity，这两个子activity在两个tab中。在其中的一个activity实现了一个公共函数，我想从父类TabHost中调用这个函数，来触发tab中的一些action。
能否从TabHost中引用activity本身来调用一个公共函数？
tabhost设置：

res = getResources();     tabHost = getTabHost();     TabHost.TabSpec spec;     Intent intent;      intent = new Intent().setClass(this home.class);    spec = tabHost.newTabSpec(""home"").setIndicator(""Groups"" res.getDrawable(R.drawable.groups)).setContent(intent);    tabHost.addTab(spec);    intent = new Intent().setClass(this messages.class);    spec = tabHost.newTabSpec(""messages"").setIndicator(""Messages"" res.getDrawable(R.drawable.messages)).setContent(intent);        tabHost.addTab(spec);

解决方案

是之前遇见过这个问题是这样解决的：
1.在manifest文件中设置intent filter
2.给子activity添加嵌套的'listener'
3.在子activity的onResume()/onPause()到register/unregister监听器
4.在TabActivity创建intent，然后广播。
AndroidManifest.xml

<activity    android:name="".MyActivity""    android:label=""@string/app_name""    <intent-filter>        <action android:name=""com.mycompany.myApp.DO_SOMETHING"" />    </intent-filter></activity>

MyActivity.java

public class MyActivity extends Activity {    private MyListener listener = null;    private Boolean MyListenerIsRegistered = false;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreated(savedInstanceState);        listener = new MyListener();    }    @Override    protected void onResume() {        super.onResume();        if (!MyListenerIsRegistered) {            registerReceiver(listener new IntentFilter(""com.mycompany.myApp.DO_SOMETHING""));            MyListenerIsRegisterd = true;        }    }    @Override    protected void onPause() {        super.onPause();        if (MyListenerIsRegistered) {            unregisterReceiver(listener);            MyListenerIsRegistered = false;        }    }    // Nested 'listener'    protected class MyListener extends BroadcastReceiver {        @Override        public void onReceive(Context context Intent intent) {            // No need to check for the action unless the listener will            // will handle more than one - let's do it anyway            if (intent.getAction().equals(""com.mycompany.myApp.DO_SOMETHING"")) {                // Do something            }        }    }}

main TabActivity

private void MakeChildDoSomething() {    Intent i = new Intent();    i.setAction(""com.mycompany.myApp.DO_SOMETHING"");    sendBroadcast(i);}

解决方案二：
希望能帮你解决问题：

 Activity currentActivity = getLocalActivityManager().getActivity(_TabHost.getCurrentTabTag());    if(currentActivity != null && currentActivity instanceof iMyActivity)    {    // 传递给子类    ((iMyActivity)currentActivity).onLaunchDelegate();    }