android – 如何在Fragment中注册Receiver

我在ListView中显示蓝牙设备.我之前在Activity中尝试过它并且它有效,但现在我必须在Fragment中包含这个ListView

很明显,这里不存在一两件事,比如registerReceiver,unregisterReceiver和RESULT_CANCELED.

protected void onResume() {
    registerReceiver(receiver,filter);
     filter = new IntentFilter(BluetoothAdapter.ACTION_disCOVERY_STARTED);
    registerReceiver(receiver,filter);
     filter = new IntentFilter(BluetoothAdapter.ACTION_disCOVERY_FINISHED);
    registerReceiver(receiver,filter);
     filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
    registerReceiver(receiver,filter);
}

@Override
protected void onPause() {
    // Todo Auto-generated method stub
    super.onPause();
    unregisterReceiver(receiver);


}

    @Override
    public void onActivityResult(int requestCode,int resultCode,Intent data) {
        // Todo Auto-generated method stub
        super.onActivityResult(requestCode,resultCode,data);
        if(resultCode == RESULT_CANCELED){
            Toast.makeText(getActivity(),"El Bluetooth debe estar activado para continuar",Toast.LENGTH_SHORT).show();
            getActivity().finish();
        }
    }

以registerReceiver,unegisterReceiver和if(resultCode == RESULT_CANCELED){开头的行’给我带来了问题.

作为一个附加的事实,我试图将其更改为Activity而不是Fragment,但我的Main类有一个错误,因为我正在使用Fragments.

解决方法

所有这些方法和变量都属于Activity类.因此,请考虑使用父级Activity of Fragment的上下文来调用它们.

您可以将所需方法称为：

getActivity().registerReceiver(receiver,filter);

和

getActivity().unregisterReceiver(receiver);

如果(resultCode为== RESULT_CANCELED){

可以替换为

if(resultCode == Activity.RESULT_CANCELED){

希望这能解决你的问题.