注册和取消注册

1、一个activity发送
       Intent intent=new     Intent().setAction("com.Notepad.NotepadView.mReceiver")
        .putExtra("BitmapName", gesName);
        sendBroadcast(intent);

2、另一个acitivty接收
       IntentFilter filter=new IntentFilter();
filter.addAction("com.Notepad.NotepadView.mReceiver");
registerReceiver(mReceiver, filter);



private BroadcastReceiver mReceiver=new BroadcastReceiver(){
@Override
public void onReceive(Context context, Intent intent) {
String BitmapName=intent.getExtras().getString("BitmapName");
String info="<img src='"+ BitmapName+"'/>";
note.getText().insert(note.getSelectionStart(),Html.fromHtml(info,imgObj,null));
}
  };


public boolean onKeyDown(int keyCode,KeyEvent event){
  if(keyCode==KeyEvent.KEYCODE_BACK){
                this.unregisterReceiver(mReceiver); //记得取消注册，否则退出时，会在注册的地方报错
  this.finish();
         }
});