Android Fragment与Activity之间的相互通信实例代码

public interface showMsgListener{
    void showMsg(String str);
  }

  private showMsgListener msgListener;

  @Override
  public void onAttach(Activity activity) {
    super.onAttach(activity);
    try {
      if(activity!=null){
        msgListener=(MainActivity)activity;
      }
    } catch (ClassCastException e) {
      throw new ClassCastException(activity.toString()
          + " must implement showMsgListener");
    }
  }

    mButton.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View view) {
        msgListener.showMsg("Hello Android!(接口)");
      }
    });

 @Override
  public void showMsg(String str) {
    Toast.makeText(MainActivity.this, str, Toast.LENGTH_SHORT).show();
  }

  private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
      String action = intent.getAction();
      if (action.equals(ACTION_NAME)) {
        String msg = intent.getStringExtra("msg");
        Toast.makeText(MainActivity.this, msg, Toast.LENGTH_SHORT).show();
      }

    }
  };

  public void registerBoradcastReceiver() {
    IntentFilter myIntentFilter = new IntentFilter();
    myIntentFilter.addAction(ACTION_NAME);
    registerReceiver(mBroadcastReceiver, myIntentFilter);
  }

  @Override
  protected void onDestroy() {
    super.onDestroy();
    unregisterReceiver(mBroadcastReceiver);
  }

public static Fragment getInstance(String msg){
    Bundle bundle = new Bundle();
    bundle.putString("msg",msg);
    MainFragment fragment=new MainFragment();
    fragment.setArguments(bundle);
    return fragment;
  }

 public void initDatas() {
    Bundle bundle=getArguments();
    if(bundle!=null){
      String msg=bundle.getString("msg");
      Toast.makeText(getActivity(), msg, Toast.LENGTH_SHORT).show();
    }
  }