android get barcode scanner input without edittext

Question

I have a physical barcode scanner and I want to get it's input, i.e the barcode, in the app without having a focused EditText.

I tried adding a KeyListener in my Activity. However, none of its implemented methods (onKeyUp, onKeyDown etc) was called.

Then I added the dispatchKeyEvent, which worked, but is never called as many times as the barcode length. Instead, before the barcode is read, some random button in my view gets focus from the barcode scanner.

String barcode = "";

@Override
public boolean dispatchKeyEvent(KeyEvent e) {
    char pressedKey = (char) e.getUnicodeChar();
    barcode += pressedKey;
    if (e.getKeyCode() == KeyEvent.KEYCODE_ENTER) {
        Toast.makeText(getApplicationContext(), "barcode--->>>" + barcode, Toast.LENGTH_LONG)
                .show();
    }

    return super.dispatchKeyEvent(e);
}

I've seen a few questions out there in SO but none really gave a concrete answer.

Answer 1

For me, for a barcode scanner (USB, reference STA pcs) works the next code:

@Override
public boolean dispatchKeyEvent(KeyEvent e) {

    if(e.getAction()==KeyEvent.ACTION_DOWN){
        Log.i(TAG,"dispatchKeyEvent: "+e.toString());
        char pressedKey = (char) e.getUnicodeChar();
        barcode += pressedKey;
    }
    if (e.getAction()==KeyEvent.ACTION_DOWN && e.getKeyCode() == KeyEvent.KEYCODE_ENTER) {
        Toast.makeText(getApplicationContext(), 
            "barcode--->>>" + barcode, Toast.LENGTH_LONG)
        .show();

        barcode="";
    }

    return super.dispatchKeyEvent(e);
}

Answer 2

First, thank you all. Since my App has to look up the barcode in the DB I had to not add the ENTER_KEY input to the Barcode String, also to prevent any focused button of going off I made the Method return false.

String barcode = "";
@Override
public boolean dispatchKeyEvent(KeyEvent e) {
    if(e.getAction()==KeyEvent.ACTION_DOWN
            && e.getKeyCode() != KeyEvent.KEYCODE_ENTER){ //Not Adding ENTER_KEY to barcode String
        char pressedKey = (char) e.getUnicodeChar();
        barcode += pressedKey;
    }
    if (e.getAction()==KeyEvent.ACTION_DOWN 
            && e.getKeyCode() == KeyEvent.KEYCODE_ENTER) {
        Log.i(TAG,"Barcode Read: "+barcode);
        barcodeLookup(barcode);// or Any method handling the data
        barcode="";
    }
        return false;
}