Question

我正在研究android应用程序，我将数据从Activity 2传递回Activity 1.我通过intent传递它。问题是在Activity 1中，它在bundle中显示值，但是当我使用bundle.getString("");时，它显示的是null值。在调试中，我正在使用bundle Bundle[{list_size=3}]。我的代码如下，请在这里帮助我。

活动1：

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if(resultCode==105){
            TextView txtCounter = (TextView) findViewById(R.id.txtCounter);
// It showing value at MBuddle, but at MBuddle it is showing null.
            Bundle MBuddle = data.getExtras();
            String MMessage = MBuddle .getString("list_size");
            txtCounter.setText(MMessage);
        }
}

活动2：

@Override
    public void onBackPressed() {
        int REQUEST_CONTACTS = 105;
        Intent intent = new Intent();
        intent.putExtra("list_size", fListContacts.size());
        setResult(REQUEST_CONTACTS, intent);
        finish();
    }

Answer 1

在这里你必须使用getIntent（）..改变你的代码

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if(resultCode==105){
        TextView txtCounter = (TextView) findViewById(R.id.txtCounter);
        // It showing value at MBuddle, but at MBuddle it is showing null.
        Bundle MBuddle = data.getExtras();
        String MMessage = MBuddle .getString("list_size");
        txtCounter.setText(MMessage);
    }
}

到

@Override
public void onBackPressed() {
    int REQUEST_CONTACTS = 105;
    Intent intent = getIntent();
    intent.putExtra("list_size", fListContacts.size());
    setResult(REQUEST_CONTACTS, intent);
    finish();
}

活性1

var socket = io.connect("http://127.0.0.1:8002");

console.log(socket); // This works

socket.on('connect', function(){
   console.log('connected');  // Does not show meaning event not fired
});

活动2

var http = require('http');
var server = http.createServer().listen(8002);
var io = require('socket.io').listen(server);
var cookie_reader = require('cookie');
var querystring = require('querystring');
var redis = require('redis');

//Configure socket.io to store cookie set by Django
io.use(function(){
    io.set('authorization', function(data, accept){
        if(data.headers.cookie){
            data.cookie = cookie_reader.parse(data.headers.cookie);
            return accept(null, true);
        }
        return accept('error', false);
    });
    // io.set('log level', 1);
    // io.set('origins', 'http://127.0.0.1:8001');
});

io.sockets.on('connection', function (socket) {
    console.log("Someone connected"); // Nothing shows
    // Create redis client
    /*client = redis.createClient();

    // Subscribe to the Redis events channel
    client.subscribe('notifications.' + socket.handshake.cookie['sessionid']);

    // Grab message from Redis and send to client
    client.on('message', function(channel, message){
        console.log('on message', message);
        socket.send(message);
    });

    // Unsubscribe after a disconnect event
    socket.on('disconnect', function () {
        client.unsubscribe('notifications.' + socket.handshake.cookie['sessionid']);
    });*/
});

Answer 2

  @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data)       

 if (requestCode == REQUEST_CODE) {
                if (resultCode == Activity.RESULT_OK) {
                    String contents = intent.getStringExtra(Intents.Scan.RESULT);
                }}
}

===============

            Intent intent = new Intent(getIntent().getAction());
            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET);
            intent.putExtra(KEY, data);
            setResult(RESULT_OK, intent);
            finish();

RESULT_OK可以是int值

Answer 3

您应该尝试更改您的活动1，如下所示。可能是因为fListContacts.size()返回int值：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if(resultCode==105){
        TextView txtCounter = (TextView) findViewById(R.id.txtCounter);
        Bundle MBuddle = data.getExtras();
        String MMessage = String.valueOf(MBuddle.getInt("list_size"));
        txtCounter.setText(MMessage);
    }
}

和活动2 将new Intent()更改为getIntent()

onActivityResult（）处的Bundel.getString（“”）给出null值

3 个答案: