Method for android to read the data of scan code module

In this paper, we share the specific code of android reading scan code module data for your reference. The specific contents are as follows

android Read Scan Module Data * * Undertake Read Data in dispatchKeyEvent Method * *

Take over the read data in dispatchKeyEvent method

private StringBuilder mScanCodeBuilder = new StringBuilder();
   @Override
    public boolean dispatchKeyEvent(@NonNull KeyEvent event) {
        LogUtil.d(TAG, "dispatchKeyEvent " + event.getAction() + ",   " + event.getKeyCode());
           checkLetterStatus(event);// Judge upper and lower case letters 
        if (event.getAction() == KeyEvent.ACTION_DOWN) {

             mScanCodeBuilder.append(getInputCode(event));
            if (event.getKeyCode() == KeyEvent.KEYCODE_ENTER) {
                // If it is Enter key, return directly 
                String scanResult = mScanCodeBuilder.toString();
                mScanCodeBuilder.setLength(0);
                LogUtil.d(TAG, "dispatchKeyEvent, " + scanResult);
                String scanResults = scanResult.replace(" ", "");
            } else {
                // Delay post If 500ms Inside, there are other events 
                mHandler.removeCallbacks(mScanningFishedRunnable);
                mHandler.postDelayed(mScanningFishedRunnable, 500);
            }

            return true;
        }
        return super.dispatchKeyEvent(event);
    }

Judge upper and lower case letters

private void checkLetterStatus(KeyEvent event) {

        int keyCode = event.getKeyCode();
        if (keyCode == KeyEvent.KEYCODE_SHIFT_RIGHT || keyCode == KeyEvent.KEYCODE_SHIFT_LEFT) {
            if (event.getAction() == KeyEvent.ACTION_DOWN) {
                // Press shift Key, representing uppercase 
                mCaps = true;
            } else {
                // Loosen shift Key for lowercase 
                mCaps = false;
            }
        }
    }

Read character method

private char getInputCode(KeyEvent event) {
    int keyCode = event.getKeyCode();
    char aChar;
    if (keyCode >= KeyEvent.KEYCODE_A && keyCode <= KeyEvent.KEYCODE_Z) {
        // Alphabet 
        aChar = (char) ((mCaps ? 'A' : 'a') + keyCode - KeyEvent.KEYCODE_A);
    } else if (keyCode >= KeyEvent.KEYCODE_0 && keyCode <= KeyEvent.KEYCODE_9) {
        // Figures 
        aChar = (char) ('0' + keyCode - KeyEvent.KEYCODE_0);
    } else {
        // Symbol 
        switch (keyCode) {
            case KeyEvent.KEYCODE_GRAVE:
                aChar = '`';
                break;
            case KeyEvent.KEYCODE_COMMA:
                aChar = ',';
                break;
            case KeyEvent.KEYCODE_APOSTROPHE:
                aChar = '\'';
                break;
            case KeyEvent.KEYCODE_POUND:
                aChar = '#';
                break;
            case KeyEvent.KEYCODE_STAR:
                aChar = '*';
                break;
            case KeyEvent.KEYCODE_PERIOD:
                aChar = '.';
                break;
            case KeyEvent.KEYCODE_MINUS:
                aChar = mCaps ? '_' : '-';
                break;
            case KeyEvent.KEYCODE_SLASH:
                aChar = '/';
                break;
            case KeyEvent.KEYCODE_BACKSLASH:
                aChar = mCaps ? '|' : '\\';
                break;
            case KeyEvent.KEYCODE_EQUALS:
                aChar = '=';
                break;
            case KeyEvent.KEYCODE_SEMICOLON:
                aChar = ';';
                break;
            case KeyEvent.KEYCODE_PLUS:
                aChar = '+';
                break;
            case KeyEvent.KEYCODE_AT:
                aChar = '@';
                break;
            case KeyEvent.KEYCODE_LEFT_BRACKET:
                aChar = '[';
                break;
            case KeyEvent.KEYCODE_RIGHT_BRACKET:
                aChar = ']';
                break;
            default:
                aChar = ' ';
                break;
        }
    }
    Log.d(TAG, "char" + aChar);
    return aChar;
}

Delay 500 millisecond correlation

private Handler mHandler = new Handler(this);
    private final Runnable mScanningFishedRunnable=new Runnable() {
        @Override
        public void run() {

        }
    };