// SwingGUIsFrameDemoPanel.java
// One each of several Swing GUI widgets in a JFrame
//** with some JPanels to improve the layout
/*
A panel is just a container of widgets.
managed by a layout manager.

JPanel myPanel = new JPanel();  //instantiate a panel
myPanel.setLayout( new GridLayout(2,4));  //specify its layou manager
myPanel.add( someGUIobject );   //add widgets to this panel

container.add (myPanel);  //add this panel to its container 
OR  //add this panel in a particular place in its container:
container.add (myPanel, BorderLayout.SOUTH); 

Or, if need a lot of panels, declare an array of them:
  JPanel[] myPanels = new JPanel[size];
then loop instantiating each panel and adding to container:
  for (int i=0; i<myPanels.length; i++) {    
      myPanels[i] = new JPanel();
      myPanels[i].setLayout(new FlowLayout());
      container.add(myPanels[i]); 
  }
 
*/ 
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;

public class SwingGUIsFrameDemoPanel
    implements ActionListener, ItemListener, ListSelectionListener {

    private JFrame outputFrame;
    private Container container;
    private JPanel [] myPanels;   //** array of JPanels
    private JLabel myLabel;
    private JTextField myTextField;
    private JPasswordField myPasswordField;
    private JButton myButton, myButton2;
    private JCheckBox myCheckBox1, myCheckBox2;
    private JRadioButton myRadioButton1, myRadioButton2;
    private ButtonGroup myButtonGroup;
    private JComboBox myComboBox;
    private JList myList;
    private JTextArea myTextArea;
    String [] names = {"fred", "jane", "steve", "susan", "bob"};

    public static void main( String [] args ) {
	SwingGUIsFrameDemoPanel myFrameDemo = new SwingGUIsFrameDemoPanel();
    }
    
    //constructor
    public SwingGUIsFrameDemoPanel() {
	outputFrame = new JFrame();
	outputFrame.setSize(600,500);
	outputFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	
	container = outputFrame.getContentPane();  
	//** the panels flow, their contents do not:
	container.setLayout( new FlowLayout() );   
	//*** 6 rows, each a JPanel with some widgets:
//	container.setLayout( new GridLayout(6,1) );   
	container.setBackground(Color.CYAN);    //panels will be default color.
	
	//**
	int size=6;  
	myPanels = new JPanel[size];   //**creates the array (but not the panels)
	for (int i=0; i<myPanels.length; i++) {
	    myPanels[i] = new JPanel();  //create a panel
	    myPanels[i].setLayout(new FlowLayout());  //specify its layout
	    container.add(myPanels[i]);   //add it to frame container
	}
	    
	myLabel = new JLabel( "My JLabel" );
	//** add to panel in element 0 of array of panels.
	//**Note this is the only difference wtih using the panel.
	myPanels[0].add( myLabel );    
	
	myTextField = new JTextField( "My JTextField", 20 );  
	myPanels[0].add( myTextField );
	myTextField.addActionListener( this ); 
	
	myPasswordField = new JPasswordField( "Type your password here",20 );
	myPanels[0].add( myPasswordField );
	myPasswordField.addActionListener( this ); 
	
	myButton = new JButton( "My JButton" );
	myPanels[1].add( myButton );
	myButton.addActionListener( this ); 
	
	
	myCheckBox1 = new JCheckBox( "My JCheckBox 1" );
	myPanels[2].add( myCheckBox1 );
	myCheckBox1.addItemListener( this ); 
	
	myCheckBox2 = new JCheckBox( "My JCheckBox 2", true );
	myPanels[2].add( myCheckBox2 );
	myCheckBox2.addItemListener( this ); 
	
	
	myRadioButton1 = new JRadioButton( "My JRadioButton 1" );
	myPanels[3].add( myRadioButton1 );
	myRadioButton1.addItemListener( this ); 
	
	myRadioButton2 = new JRadioButton( "My JRadioButton 2" );
	myPanels[3].add( myRadioButton2 );
	myRadioButton2.addItemListener( this ); 
	
	myButtonGroup = new ButtonGroup();
	myButtonGroup.add(myRadioButton1);
	myButtonGroup.add(myRadioButton2);
	
	myComboBox = new JComboBox(names);
	myComboBox.setMaximumRowCount(3);
	myPanels[4].add( myComboBox );
	myComboBox.addItemListener( this );

	myList = new JList(names);
	myList.setVisibleRowCount(3);
	myList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
	myPanels[4].add(new JScrollPane(myList));  
	myList.addListSelectionListener( this );

	//**size is problematic... only partially visible if array of panels is in GridLayout
	//but FlowLayout frame container is OK.
	myTextArea = new JTextArea(10,40); 
	myPanels[5].add( new JScrollPane(myTextArea));
	
	outputFrame.setVisible(true);
    }

    
    // event handler for JButton, JTextField and JPasswordField events.
    public void actionPerformed( ActionEvent event ) {
	if ( event.getSource() == myButton ) {
	    JOptionPane.showMessageDialog(null,"myButton got it");
	    myTextArea.append("myButton pressed\n");
	}
	
	else if ( event.getSource() == myTextField ) {
	    //2 ways to get the text of the textfield:
	    JOptionPane.showMessageDialog(null,"myTextField got it one way: " +
					  event.getActionCommand() );
	    JOptionPane.showMessageDialog(null,"myTextField got it the other way: " +
					  myTextField.getText() );  //***access the text
	    myTextArea.append("myTextField: " + myTextField.getText() + "\n");
	    myTextField.setText( "" );   //***change the text
	}
	else if ( event.getSource() == myPasswordField ) {
	    JOptionPane.showMessageDialog(null,"myPasswordField got it: " +
					  event.getActionCommand()+ "  oops" );
	    myTextArea.append("myPasswordField entered\n");
	    myPasswordField.setText( "" );
	}
    } 
    
    
    
    // event handler for JCheckBox, JRadioButton and JComboBox events.
    public void itemStateChanged( ItemEvent event ) {
	if ( event.getSource() == myCheckBox1 ) {
	    if (event.getStateChange() == ItemEvent.SELECTED) {
		JOptionPane.showMessageDialog(null,"myCheckBox 1 selected");
		myTextArea.append("myCheckBox 1 selected\n");
	    }
	    else if (event.getStateChange() == ItemEvent.DESELECTED) {
		JOptionPane.showMessageDialog(null,"myCheckBox 1 deselected");
		myTextArea.append("myCheckBox 1 deselected\n");
	    }
	}
	else if ( event.getSource() == myCheckBox2 ) {
	    if ( myCheckBox2.isSelected() ) {   //alternate way to see which event happened
		JOptionPane.showMessageDialog(null,"myCheckBox 2 selected");
		myTextArea.append("myCheckBox 2 selected\n");
	    }
	    else if ( ! myCheckBox2.isSelected() ) {
		JOptionPane.showMessageDialog(null,"myCheckBox 2 deselected");
		myTextArea.append("myCheckBox 2 deselected\n");
	    }
	}
	
	else if ( event.getSource() == myRadioButton1 ) {
	    if ( myRadioButton1.isSelected() ) {
		JOptionPane.showMessageDialog(null,"myRadioButton 1 selected");
		myTextArea.append("myRadioButton 1 selected\n");
	    }
	}
	else if ( event.getSource() == myRadioButton2 ) {
	    if ( myRadioButton2.isSelected() ) {
		JOptionPane.showMessageDialog(null,"myRadioButton 2 selected");
		myTextArea.append("myRadioButton 2 selected\n");
	    }
	}

	else if ( event.getSource() == myComboBox ) {
	    if ( event.getStateChange() == ItemEvent.SELECTED ) {
		int i = myComboBox.getSelectedIndex();  //index of combobox items 
		JOptionPane.showMessageDialog(null,"myComboBox selected index:" +
					      i + "\nitem value: " + names[i]);
		myTextArea.append("myComboBox selected index: " +
				  i + "   item value: " + names[i] + "\n");
	    }
	}
    } 

    //event handler for JList.
    public void valueChanged( ListSelectionEvent event ) {
	if ( event.getSource() == myList ) {
            int i = myList.getSelectedIndex();  //similar to combobox
	    JOptionPane.showMessageDialog(null,"myList index: " + i +
					"\nitem value: " + names[i]);
	    myTextArea.append("myList selected index: " +
			      i + "   item value: " + names[i] + "\n");
	}				  
    }
}