TabHost页和子Activity之间的通讯

abHost的各个Tab页，都是由activity组成。

现在，某个子Activity中处理数据后，要自动跳转到另外一个Tab页中。这样，需要有个TabHost页和子Activity之间的通讯的机制。

子Activity通知TabHost：

1、通过广播方式

1）在TabHost中定义广播

定义变量

protected MessageBroadcastReceiver myReceiver = null;

在onCreate中注册： 加入receiveBroadcast();

private void receiveBroadcast() { myReceiver = new MessageBroadcastReceiver(); //Log.d(LOG_TAG, "receiveBroadcast() ::::: " + myReceiver.hashCode()); IntentFilter intentFilter = new IntentFilter("android.intent.action.MAIN"); registerReceiver(myReceiver, intentFilter); }

在onDestroy中释放广播

if (myReceiver != null) unregisterReceiver(myReceiver);

MessageBroadcastReceiver类定义:

public class MessageBroadcastReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { try { String action = intent.getAction(); if (action.equals("android.intent.action.MAIN")) { switch (intent.getIntExtra("msg", 0)) { case Constant.BROADCAST_KEY_TABHOST_CHANGE: { int tabIndex = intent.getIntExtra("tabIndex", 0); animateChangeTab(tabIndex); } } } } catch (Exception e) { e.printStackTrace(); Log.v(LOG_TAG, e.getMessage()); } } }

2）在子Activity中调用

Intent intent = new Intent("android.intent.action.MAIN");

intent.putExtra("msg", Constant.BROADCAST_KEY_TABHOST_CHANGE);

intent.putExtra("tabIndex", 0);

sendBroadcast(intent);

2、通过handler接收消息

1）在TabHost中定义Handler

// 得到主线程的Looper对象

Looper looper = Looper.myLooper();

// 这个myHandler由主线程创建所以它与主线程关联

public MessageHandler msgHandler = new MessageHandler(looper);

private void showMessage(String message) {

// 发送本次信息

msgHandler.removeMessages(0);

Message m = msgHandler.obtainMessage(1, 1, 1, message); // 构造要传递的消息

msgHandler.sendMessage(m); // 发送消息: 系统会自动调用handleMessage 方法来处理消息

}

public class MessageHandler extends Handler {

public MessageHandler(Looper looper) {

super(looper);

}

@Override

public void handleMessage(Message msg) { // 处理消息

switch (msg.what) {

case Constant.BROADCAST_KEY_TABHOST_CHANGE:

int tabIndex = (Integer) msg.obj;

animateChangeTab(tabIndex);

break;

default:

Toast.makeText(getApplicationContext(), msg.obj.toString(),

Toast.LENGTH_SHORT).show();

break;

}

}

}

2）在子Activity中调用

BasketballMainActivity t= (BasketballMainActivity) getParent();

Message message = new Message();

message.what = Constant.BROADCAST_KEY_TABHOST_CHANGE;

message.obj = 0;

t.msgHandler.sendMessage(message);

TabHost通知子Activity：

1、子Activity是活动的

在TabHost中增加

Activity currentActivity = getCurrentActivity();

if (currentActivity instanceof A) {

((A) currentActivity).处理方法XXX;

}

2、子Activity是不是活动的

在子Activity的

@Override

protected void onResume() {

//添加逻辑即可

}