package swingdemo;

import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.event.*;

public class MyFrame extends JFrame implements ActionListener {
  private JTextArea textArea = new JTextArea();

  public MyFrame() {
    this.setTitle("SwingDemo Frame");

    //--------------------------------------
    //set the layout to BorderLayout
    //--------------------------------------
    this.getContentPane().setLayout(new BorderLayout());

    //-----------------------------------
    //creating graphical components
    //-----------------------------------
    textArea.setText("");
    JScrollPane scrollPane = new JScrollPane(textArea);

    JButton clearTextButton = new JButton("Clear TextArea");
    JButton appendTextButton = new JButton("Append Text");
    JButton setTextButton = new JButton("Set Text");

    JPanel panel = new JPanel();
    panel.add(setTextButton);
    panel.add(appendTextButton);
    panel.add(clearTextButton);

    this.getContentPane().add(scrollPane, BorderLayout.CENTER);
    this.getContentPane().add(panel, BorderLayout.SOUTH);

    //---------------------------------
    //set the event handling
    //---------------------------------
    setTextButton.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
        textArea.setText("Ein wenig Text");
      }
    });
    appendTextButton.addActionListener(new AppendTextActionListener());
    clearTextButton.addActionListener(this);

    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    /*this.addWindowListener(new WindowAdapter(){
      public void windowClosing(WindowEvent e){
        System.exit(0);
      }
    });*/
  }

  /**
  *  Example for an ActionListener as inner class
  */
  private class AppendTextActionListener implements ActionListener{
    public void actionPerformed(ActionEvent e){
      textArea.append("Ein wenig mehr Text");
    }
  }

  public void actionPerformed(ActionEvent e){
      textArea.setText("");
  }

  public static void main(String[] args){
    MyFrame frame = new MyFrame();
    frame.setSize(400,500);
    frame.setVisible(true);
    //frame.pack();frame.show();
  }
}