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javastringjtextfieldreadline

Java JTextField Converting to upper/lowercase while writing

I've got question regarding to typing in JTextField. My program search thru few csv files and look for specified in JTextField string. I have add to readLine function ".toLowerCase" to read all strings as lowercase. Is it possible to set JTextField to automatically convert uppercase to lower case while writing to JTextField?

if (line.toLowerCase().contains(searchedString))...

Solution

  • Yes, you can use the KeyListener and when a key is pressed in the textfield, you will make the input string lowerCase while keeping the cursor position where it was. Like the code below:

    jTextField1.addKeyListener(new KeyListener() {
    @Override
    public void keyTyped(KeyEvent e) {

    }

    @Override
    public void keyPressed(KeyEvent e) {
    }

    @Override
    public void keyReleased(KeyEvent e) {
        int pos = jTextField1.getCaretPosition();
        jTextField1.setText(jTextField1.getText().toLowerCase());
        jTextField1.setCaretPosition(pos);
    }
});

    Source: