Result activity closes main activity when pressing back button

Question

I'm developing an app, where I have a button wich displays a dialog Activity where it finds bluetooth devices.

It works fine, but if I press de back button while in this activity, instead of returning to the main activity, it destroys it.

The dialog activity is the same that in the BluetoothChat example. This is the code of the main activity:

   /*********************
 * 
 * ONCREATE
 * 
 ********************/

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    final Button button1 = (Button) findViewById(R.id.button1);
    final Button button2 = (Button) findViewById(R.id.button2);



    /**Call to the Configuration activity*/
    button2.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            lanzarConfiguracion (null);
        }
    });

    /**Call to the DeviceList activity*/
    button1.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            lanzarBusqueda (null);
        }
    });

    GlobalVar.mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

    if (GlobalVar.mBluetoothAdapter == null) {
        Toast.makeText(this, "Bluetooth is not available", Toast.LENGTH_LONG).show();
        finish();
        return;
    }
}



/*********************
 * 
 * ONSTART
 * 
 ********************/

@Override
public void onStart() {
    super.onStart();

    if (!GlobalVar.mBluetoothAdapter.isEnabled()) {

        Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
        startActivityForResult(enableBtIntent, GlobalVar.REQUEST_ENABLE_BT);
    }
    else {
        if (GlobalVar.mTransmission == null) setupCaller();
    }
}



/*********************
 * 
 * ONDESTROY
 * 
 ********************/

@Override
public void onDestroy() {
    super.onDestroy();
    /**Stop the Bluetooth chat services*/
    if (GlobalVar.mTransmission != null) GlobalVar.mTransmission.stop();
}



/*********************
 * 
 * OPTIONS
 * 
 ********************/

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    /**Inflate the menu; this adds items to the action bar if it is present.*/
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.info:
            lanzarInfo(null);
            break;
        case R.id.config:
            lanzarConfiguracion(null);
            break;
    }
    return true; /** true -> consumimos el item, no se propaga*/
}




@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    switch (requestCode) {
        case GlobalVar.REQUEST_CONNECT_DEVICE:
            /**When DeviceListActivity returns with a device to connect*/
            if (resultCode == Activity.RESULT_OK) {
                connectDevice(data);
            }
        case GlobalVar.REQUEST_ENABLE_BT:
            /**When the request to enable Bluetooth returns*/
            if (resultCode == Activity.RESULT_OK) {
                /**Bluetooth is now enabled, so set up a chat session*/
                setupCaller();
            } else {
                /**User did not enable Bluetooth or an error occurred*/
                Toast.makeText(this, R.string.bt_not_enabled_leaving, Toast.LENGTH_SHORT).show();
                finish();
            }
            break;
    }

}


private void connectDevice(Intent data) {
    /**Get the device MAC address*/
    String address = data.getExtras().getString(DeviceListDialog.EXTRA_DEVICE_ADDRESS);
    /**Get the BluetoothDevice object*/
    BluetoothDevice device = GlobalVar.mBluetoothAdapter.getRemoteDevice(address);
    /**Attempt to connect to the device*/
    try{
        GlobalVar.mTransmission.connect(device);
    }catch(Exception ex) {
    }
}


private final void setStatus(int resId) {
    final ActionBar actionBar = getActionBar();
    actionBar.setSubtitle(resId);
}

private final void setStatus(CharSequence subTitle) {
    final ActionBar actionBar = getActionBar();
    actionBar.setSubtitle(subTitle);
}


/**
 * The Handler that gets information back from the Transmission
 */
public final Handler mHandler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
        switch (msg.what) {
            case GlobalVar.MESSAGE_STATE_CHANGE:
                switch (msg.arg1) {
                    case GlobalVar.STATE_CONNECTED:
                        setStatus(getString(R.string.title_connected_to, GlobalVar.mConnectedDeviceName));
                        GlobalVar.mCommunicationArrayAdapter.clear();
                        break;
                    case GlobalVar.STATE_CONNECTING:
                        setStatus(R.string.title_connecting);
                        break;
                    case GlobalVar.STATE_LISTEN:
                    case GlobalVar.STATE_NONE:
                        setStatus(R.string.title_not_connected);
                        break;
                }
                break;
            case  GlobalVar.MESSAGE_WRITE:
                byte[] writeBuf = (byte[]) msg.obj;
                /**construct a string from the buffer*/
                String writeMessage = new String(writeBuf);
                GlobalVar.mCommunicationArrayAdapter.add("Me:  " + writeMessage);
                break;
            case  GlobalVar.MESSAGE_READ:
                byte[] readBuf = (byte[]) msg.obj;
                /**construct a string from the valid bytes in the buffer*/
                String readMessage = new String(readBuf, 0, msg.arg1);
                GlobalVar.mCommunicationArrayAdapter.add(GlobalVar.mConnectedDeviceName+":  " + readMessage);
                break;
            case  GlobalVar.MESSAGE_DEVICE_NAME:
                /**save the connected device's name*/
                GlobalVar.mConnectedDeviceName = msg.getData().getString(GlobalVar.DEVICE_NAME);
                Toast.makeText(getApplicationContext(), "Connected to " + GlobalVar.mConnectedDeviceName, Toast.LENGTH_SHORT).show();
                break;
            case  GlobalVar.MESSAGE_TOAST:
                Toast.makeText(getApplicationContext(), msg.getData().getString(GlobalVar.TOAST), Toast.LENGTH_SHORT).show();
                break;
        }
    }
};


public void setupCaller() {
    /**Initialize the Transmission to perform bluetooth connections*/
    GlobalVar.mTransmission = new Transmission(this, mHandler);
    /**Initialize the array adapter here for avoid errors with the Handler above*/
    //GlobalVar.mCommunicationArrayAdapter = new ArrayAdapter<String>(this, R.layout.message);
}





/*********************
 * 
 * INTENTS
 * 
 ********************/

public void lanzarConfiguracion (View view) {
    Intent i = new Intent (this, Configuration.class);
    startActivity(i);
}
public void lanzarInfo (View view) {
    Intent i = new Intent(this, Info.class);
    startActivity(i);
}
public void lanzarBusqueda (View view) {
    Intent serverintent = new Intent(this, DeviceListDialog.class);
    startActivityForResult(serverintent, GlobalVar.REQUEST_CONNECT_DEVICE);
}

}

Answer 1

You forgot the break statement before

    case GlobalVar.REQUEST_ENABLE_BT:

The execution continues in this case, and reaches the finish() statement because the default RESULT_CODE for back press is Activity.RESULT_CANCEL.