Sample 004

package wiki.snippets;

import java.awt.FlowLayout;
import java.io.File;

import javax.swing.JFrame;

import org.beanfabrics.model.TextPM;
import org.beanfabrics.model.PMManager;
import org.beanfabrics.support.Validation;
import org.beanfabrics.swing.BnTextField;
/**
 * Sample for extending a TextPM to add a custom validation
 */
public class Sample004 {
    public static void main(String[] args) {
        
        // We define a subclass of TextPM for holding a directory path
        /**
         * This is a pM for a directory path. It will be valid only 
         * when the directory exists.
         */
        class DirectoryPathPM extends TextPM {
            
            public DirectoryPathPM() {
                PMManager.setup(this);
                setMandatory(true);
            }
            
            /**
             * Evaluates if the text content is a path to an existing directory.
             * @return true, if the text is a path to an existing directory
             */
            @Validation(message="This is not a valid directory")
            public boolean isDirectory() {
                return new File(this.getText()).isDirectory();
            }
        }
        
        // create an instance
        DirectoryPathPM model = new DirectoryPathPM();
        // set the text to the path of the user's home directory
        model.setText( System.getProperty("user.home"));
        
        // create a textfield
        BnTextField textfield = new BnTextField();
        textfield.setColumns(30);

        // bind the textfield to the model
        textfield.setPresentationModel(model);

        // show the textfield inside a window
        JFrame frame = new JFrame("Enter path to directory");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout( new FlowLayout());
        frame.add(textfield);
        frame.setSize(400, 100);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
        
    }
}