从GUI Builder验证InputVerifier

Question

I created some JTextFields and JComboBox using Gui Builder(Drag and drop) and added a submit trigger JButton . I wanted to validate the Swing Controls by checking if textfields are empty calling the method verify() in my GUI.

validation class

public class validation extends InputVerifier
{
  @Override
  public boolean verify(JComponent input) 
  {
    String text = null;
    String cb = null;

    if(input instanceof JTextField)
    {
        text = ((JTextField) input).getText();
    }
    else if(input instanceof JComboBox)
    {
        cb = ((JComboBox) input).getSelectedItem().toString();
    }

    return true;
  }
}

AddEmployee

I already created a instance of my class validation.

public class AddEmployee extends javax.swing.JInternalFrame{

/**
 * Creates new form AddEmployee
 */
validation v = new validation();

   private void addButtonActionPerformed(java.awt.event.ActionEvent evt){
      String lastName = tfLastName.getText();
      String firstName = tfFirstName.getText();

      tfLastName.setName("lastName");
      tfFirstName.setName("firstName");

      v.verify(tfLastName,tfFirstName);
   }

}//end of AddEmployee

When I'm trying to passed the variable names of my JTextFields in verify() method it throws me a error.

no suitable method found for verify(JTextFields,JTextFields) method InputVerifier.verify is not applicable

What I did I created a void method verify() under validation class.

public void verify(JTextField tfLastName, JTextField tfFirstName) {

}

Question

• Where should I validate textfields? Should I validate under AddEmployee or validation class?

Any help or tips I would greatly appreciated!

Answer 1

Best practice: when you create the JTextField assign the verifier to it:

  tfLastName.setInputVerifier(new validation());

BTW: Use correct java naming convention: V alidation