private void validateField() {
		if (isFieldValid()) {
			setBackground(defaultBackgroundColor == null ? VALID_COLOR : defaultBackgroundColor);
		}
		else {
			setBackground(INVALID_COLOR);
		}
	}
Checks the validity of the field and sets the appropriate
field attributes.
Ghidra/Framework/Docking/src/main/java/docking/widgets/textfield/HintTextField.java