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Custom maximize, minimize buttons

I created custom buttons for maximize, minimize and exit. And everything is working, with one exception, program does not remember in which state window was, before minimization. So my question is, is there a way, program to remember window state before minimization, and restore that state, and not to return only on NORMAL state?
My solution for:
maximize:
JButton btnO = new JButton("O");
btnO.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
if (frame.getExtendedState() == JFrame.MAXIMIZED_BOTH) {
frame.setExtendedState(JFrame.NORMAL);
} else {
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
}
}
});
and Minimize:
JButton btnMinimize = new JButton("-");
btnMinimize.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
frame.setExtendedState(JFrame.ICONIFIED);
}
});

You can take the ComponentListener approach and restore its state when the component (in your case, the frame), is resized. Some extra comments inside the code.
Take a look at this example:
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
public class FrameState extends JFrame {
private static final long serialVersionUID = 1965751967944243251L;
private int state = -1; // Variable to keep the last state.
public FrameState() {
super("Nothing :)");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JButton b = new JButton("-");
b.addActionListener(e -> {
state = getExtendedState(); //Store the state before "-" is pressed
setExtendedState(JFrame.ICONIFIED);
});
JButton o = new JButton("O");
o.addActionListener(e -> {
if (getExtendedState() == JFrame.MAXIMIZED_BOTH) {
setExtendedState(JFrame.NORMAL);
} else {
setExtendedState(JFrame.MAXIMIZED_BOTH);
}
});
getContentPane().setLayout(new FlowLayout());
getContentPane().add(o);
getContentPane().add(b);
setSize(new Dimension(300, 300));
setLocationRelativeTo(null);
addComponentListener(new ComponentListener() {
#Override
public void componentShown(ComponentEvent arg0) {
}
#Override
public void componentResized(ComponentEvent arg0) {
if (state != -1) {
setExtendedState(state); //Restore the state.
state = -1; //If it is not back to -1, window won't be resized properly by OS.
}
}
#Override
public void componentMoved(ComponentEvent arg0) {
}
#Override
public void componentHidden(ComponentEvent arg0) {
}
});
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
FrameState f = new FrameState();
f.setVisible(true);
});
}
}

You can use this code in JButton to maximize and restore JFrame.
In order to perform this function, you have import JFrame even though the JFrame has been extended in your java class.
if(getExtendedState()==NORMAL)
{
setExtendedState(MAXIMIZED_BOTH);
}
else
{
setExtendedState(NORMAL);
}

JMenuItem.setSelected() does not alter appearance of selected item?

I wish to programmatically cause a particular item on a menu to be selected and to display as such so that if Enter is pressed, the corresponding action will be performed. Ubnfortunately I find that neither JMenuItem.setSelected(), nor JPopupMenu.setSelectedItem() does what I want. Basically I want to happen what happens when either the arrow key is pressed or the mouse moves into the space of a particular item - the background color alters, indicating the selection. I did not program that, it just happens. Why don't these APIs do the same thing? This is driving me nuts. It should not be this hard. Is there some API that does what I want?

This kinda worked:
JMenuItem#setArmed(boolean);
although you don't see it unless you traverse the JMenus to get there. Perhaps if you call that on each menu above it?
EDIT:
Perhaps you want an accelerator for your menu item?
See: How To Use Menus: Enabling Keyboard Operation

java.awt.Robot can do Trick ;)
Consider the code Given below:
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JMenuBar;
import javax.swing.JOptionPane;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
import java.awt.Dimension;
import java.awt.BorderLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.Robot;
public class JMenuFrame extends JFrame implements ActionListener
{
JMenuBar bar;
JMenu menu ;
String[] items;
JMenuItem[] menuItems;
JButton start;
Robot robot;
public void prepareAndShowGUI()
{
try
{
robot = new Robot();
}
catch (Exception ex){}
bar = new JMenuBar();
menu = new JMenu("File");
items = new String[]{"Open","Save","Save As","Quit"};
menuItems = new JMenuItem[items.length];
start = new JButton("Click me");
for (int i = 0 ; i < items.length ; i++)
{
menuItems[i] = new JMenuItem(items[i]);
menuItems[i].addActionListener(this);
menu.add(menuItems[i]);
}
bar.add(menu);
setJMenuBar(bar);
start.addActionListener(this);
getContentPane().add(start,BorderLayout.SOUTH);
setPreferredSize(new Dimension(300,400));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent evt)
{
if ("Click me".equals(evt.getActionCommand()))
{
menu.doClick();
if (robot!=null)
{
for (int i = 0 ; i<=2 ; i++) //Suppose you want to select 3rd MenuItem
{
if (!menuItems[i].isEnabled())
{
continue;
}
robot.keyPress(KeyEvent.VK_DOWN);
robot.keyRelease(KeyEvent.VK_UP);
}
}
}
else
{
JOptionPane.showMessageDialog(this,evt.getActionCommand()+" is pressed","Information",JOptionPane.INFORMATION_MESSAGE);
}
}
public static void main(String st[])
{
SwingUtilities.invokeLater( new Runnable()
{
public void run()
{
JMenuFrame mf = new JMenuFrame();
mf.prepareAndShowGUI();
}
});
}
}

It's ugly as sin, but this, in connection with splungebob's setArmed() answer above is the full solution:
First, make the menu a MenuKeyListener and add it a a MenuKeyListener to itself. Then:
public void menuKeyReleased(MenuKeyEvent e) {
if (e.getModifiers() == 0) {
switch (e.getKeyCode()) {
case KeyEvent.VK_ENTER:
case KeyEvent.VK_SPACE:
for (MenuElement elem : this.getSubElements()) {
if (elem instanceof JMenuItem) {
JMenuItem item = (JMenuItem) elem;
if (item.isArmed()) {
Action action = item.getAction();
if (action != null) {
action.actionPerformed(new ActionEvent(this, 0, null));
e.consume();
setVisible(false);
}
}
}
}
}
}
}
I can't believe that this was this difficult. Swing has definite limitations when it comes to building keyboard-centric interfaces.

Although I'm not sure I agree with the requirements (see my comment in the OP), I still wanted to give it a crack. The first half of the code is just setting up the GUI so that the condition can be creted by the user.
- A menu is created with 3 items, and 3 separate checkboxes are created to control the state of the menu items.
- If at any time only one menu item is enabled, auto-expand the menu and "pre-select" the item. The code to auto-expand the menu was ripped from JMenu.
- Add a MenuKeyListener to the menu to capture the user hitting the space bar while the menu tree is expanded.
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
public class JMenuDemo implements Runnable
{
private final String[] ACTIONS = new String[]{"Open", "Print", "Close"};
private JMenu fileMenu;
private JMenuItem[] menuItems;
private JCheckBox[] checkBoxes;
public static void main(String args[])
{
SwingUtilities.invokeLater(new JMenuDemo());
}
public void run()
{
JPanel panel = new JPanel(new GridLayout(0,1));
panel.setBorder(BorderFactory.createTitledBorder("Enabled"));
menuItems = new JMenuItem[ACTIONS.length];
checkBoxes = new JCheckBox[ACTIONS.length];
for (int i = 0; i < ACTIONS.length; i++)
{
final int index = i;
final String action = ACTIONS[i];
menuItems[i] = new JMenuItem(action);
menuItems[i].setAccelerator(KeyStroke.getKeyStroke(action.charAt(0),
ActionEvent.ALT_MASK));
menuItems[i].setMnemonic(action.charAt(0));
menuItems[i].addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
System.out.println(action);
}
});
checkBoxes[i] = new JCheckBox(action);
checkBoxes[i].setSelected(true);
checkBoxes[i].addItemListener(new ItemListener()
{
public void itemStateChanged(ItemEvent event)
{
checkBoxChanged(index);
}
});
panel.add(checkBoxes[i]);
}
JFrame frame = new JFrame("Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setJMenuBar(createJMenuBar());
frame.add(panel, BorderLayout.SOUTH);
frame.setSize(300, 400);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private void checkBoxChanged(int index)
{
menuItems[index].setEnabled(checkBoxes[index].isSelected());
evaluate();
}
private JMenuBar createJMenuBar()
{
fileMenu = new JMenu("File");
fileMenu.setMnemonic('F');
fileMenu.addMenuKeyListener(new MenuKeyListener()
{
#Override
public void menuKeyTyped(MenuKeyEvent event)
{
autoClick(event);
}
#Override
public void menuKeyPressed(MenuKeyEvent event) {}
#Override
public void menuKeyReleased(MenuKeyEvent event) {}
});
for (int i = 0; i < menuItems.length; i++)
{
fileMenu.add(menuItems[i]);
}
JMenuBar menuBar = new JMenuBar();
menuBar.add(fileMenu);
return menuBar;
}
private void autoClick(MenuKeyEvent event)
{
if (event.getModifiers() == 0 && event.getKeyChar() == KeyEvent.VK_SPACE)
{
for (JMenuItem menuItem : menuItems)
{
if (menuItem.isArmed())
{
menuItem.doClick();
MenuSelectionManager.defaultManager().setSelectedPath(null);
}
}
}
}
private void evaluate()
{
JMenuItem onlyOne = null;
for (JMenuItem menuItem : menuItems)
{
menuItem.setArmed(false);
if (menuItem.isEnabled())
{
if (onlyOne == null)
{
onlyOne = menuItem;
}
else
{
onlyOne = null;
break;
}
}
}
// Show the path if only one is enabled
if (onlyOne != null)
{
onlyOne.setArmed(true);
MenuElement me[] = buildMenuElementArray(fileMenu);
MenuSelectionManager.defaultManager().setSelectedPath(me);
}
}
/*
* Copied from JMenu
*/
private MenuElement[] buildMenuElementArray(JMenu leaf)
{
Vector<JComponent> elements = new Vector<JComponent>();
Component current = leaf.getPopupMenu();
while (true)
{
if (current instanceof JPopupMenu)
{
JPopupMenu pop = (JPopupMenu) current;
elements.insertElementAt(pop, 0);
current = pop.getInvoker();
}
else if (current instanceof JMenu)
{
JMenu menu = (JMenu) current;
elements.insertElementAt(menu, 0);
current = menu.getParent();
}
else if (current instanceof JMenuBar)
{
JMenuBar bar = (JMenuBar) current;
elements.insertElementAt(bar, 0);
MenuElement me[] = new MenuElement[elements.size()];
elements.copyInto(me);
return me;
}
}
}
}

jMenu1.doClick(); // this open the menu again

I found this setSelectedPath() works well in unison of mouse hover, unlike using menuItem.setArmed()
MenuSelectionManager.defaultManager().setSelectedPath(new MenuElement[]{popupMenu, menuItem});

getting right click location from popmenu action event

I have a java program that opens a popup menu when right clicked in a JPanel. When any of the popup menu items are clicked, I want to print the location of the right click that triggered the popupmenu in the terminal. How do I do this? How do I get the location of where the right click happened from within popup action events?
How does the code change if the popup menu is in a JComponent?
Here is the program.
import java.awt.EventQueue;
import java.awt.event.*;
import javax.swing.*;
public class MenuTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
MenuFrame frame = new MenuFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}
class MenuFrame extends JFrame
{
public MenuFrame()
{
setTitle("MenuTest");
setSize(300, 200);
Action cutAction = new TestAction("Cut");
Action copyAction = new TestAction("Copy");
Action pasteAction = new TestAction("Paste");
JPopupMenu popup = new JPopupMenu();
popup.add(cutAction);
popup.add(copyAction);
popup.add(pasteAction);
JPanel panel = new JPanel();
panel.setComponentPopupMenu(popup);
add(panel);
panel.addMouseListener(new MouseAdapter() {});
}
class TestAction extends AbstractAction
{
public TestAction(String name)
{
super(name);
}
public void actionPerformed(ActionEvent event)
{
System.out.println("Right click happened at ?"); // How do I get right click location?
}
}
}

Add a mouse listener to pressed events, (clicked events get captured by popup):
panel.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
clickLocation.setSize(e.getX(), e.getY());
}
});
Action cutAction = new TestAction("Cut", clickLocation);
Action copyAction = new TestAction("Copy", clickLocation);
Action pasteAction = new TestAction("Paste", clickLocation);
Print out the dimension:
private Dimension clickLocation;
public TestAction(String name, Dimension clickLocation) {
super(name);
this.clickLocation = clickLocation;
}
public void actionPerformed(ActionEvent event) {
System.out.println("Right click happened at " + clickLocation);
}

you were on the right track. i personally prefer to show it manually in the MouseAdapter so i can add methods on other mouseevents. for this you probably need to remove the panel.setComponentPopupMenu(popup);
panel.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent arg0) {
if (arg0.getButton() == MouseEvent.BUTTON3) { //Button3 is rightclick
popup.show(panel, arg0.getX(), arg0.getY());
}
}
});

Here is the code that I was looking for. Thank you Schippi and Garret for your help.
import java.awt.EventQueue;
import java.awt.event.*;
import javax.swing.*;
import java.awt.geom.*;
public class MenuTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
MenuFrame frame = new MenuFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}
class MenuFrame extends JFrame
{
public MenuFrame()
{
setTitle("MenuTest");
setSize(300, 200);
Action cutAction = new TestAction("Cut");
Action copyAction = new TestAction("Copy");
Action pasteAction = new TestAction("Paste");
JPopupMenu popup = new JPopupMenu();
popup.add(cutAction);
popup.add(copyAction);
popup.add(pasteAction);
JPanel panel = new JPanel();
panel.setComponentPopupMenu(popup);
add(panel);
panel.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
clickLocation= e.getPoint();
}
});
}
class TestAction extends AbstractAction
{
public TestAction(String name)
{
super(name);
}
public void actionPerformed(ActionEvent event)
{
System.out.println("Right click happened at (" + clickLocation.getX()+"," + clickLocation.getY()+ ")");
}
}
private Point2D clickLocation;
}

Or if you don't want to get it from the event.
Point mousepospoint=null;
if((mousepospoint=componentname.getMousePosition()) != null){
//mouseposArray[0]=mousepospoint.x;
//mouseposArray[1]=mousepospoint.y;
mousepoints(mousepospoint.x,mousepospoint.y);
}//enif
int[] mouseposArray={0,0};
// requires a function to return it if mouseposArray[] is global
protected int[] mousepoints(int xpo,int ypo){
mouseposArray=new int[2];
mouseposArray[0]=xpo;
mouseposArray[1]=ypo;
return mouseposArray;
}//enmeth

how to drag and drop files from a directory in java

I want to implement dragging and dropping of files from a directory such as someones hard drive but can't figure out how to do it. I've read the java api but it talks of color pickers and dragging and dropping between lists but how to drag files from a computers file system and drop into my application. I tried writing the transferhandler class and a mouse event for when the drag starts but nothing seems to work. Now I'm back to just having my JFileChooser set so drag has been enabled but how to drop?
Any info or point in the right direction greatly appreciated.
import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import javax.swing.BorderFactory;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
import javax.swing.filechooser.FileFilter;
public class FileChooserDemo
extends JPanel
implements ActionListener
{
JLabel selectedFileLabel;
JList selectedFilesList;
JLabel returnCodeLabel;
public FileChooserDemo()
{
super();
createContent();
}
void initFrameContent()
{
JPanel closePanel = new JPanel();
add(closePanel, BorderLayout.SOUTH);
}
private void createContent()
{
setLayout(new BorderLayout());
JPanel NorthPanel = new JPanel();
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("File");
JMenuItem quit = new JMenuItem("Quit");
menuBar.add(menu);
menu.add(quit);
NorthPanel.add(menu,BorderLayout.NORTH);
JPanel buttonPanel = new JPanel(new GridLayout(7,1 ));
JButton openButton = new JButton("Open...");
openButton.setActionCommand("OPEN");
openButton.addActionListener(this);
buttonPanel.add(openButton);
JButton saveButton = new JButton("Save...");
saveButton.setActionCommand("SAVE");
saveButton.addActionListener(this);
buttonPanel.add(saveButton);
JButton delete = new JButton("Delete");
delete.addActionListener(this);
delete.setActionCommand("DELETE");
buttonPanel.add(delete);
add(buttonPanel, BorderLayout.WEST);
// create a panel to display the selected file(s) and the return code
JPanel displayPanel = new JPanel(new BorderLayout());
selectedFileLabel = new JLabel("-");
selectedFileLabel.setBorder(BorderFactory.createTitledBorder
("Selected File/Directory "));
displayPanel.add(selectedFileLabel, BorderLayout.NORTH);
selectedFilesList = new JList();
JScrollPane sp = new JScrollPane(selectedFilesList);
sp.setBorder(BorderFactory.createTitledBorder("Selected Files "));
MouseListener listener = new MouseAdapter()
{
public void mousePressed(MouseEvent me)
{
JComponent comp = (JComponent) me.getSource();
TransferHandler handler = comp.getTransferHandler();
handler.exportAsDrag(comp, me, TransferHandler.MOVE);
}
};
selectedFilesList.addMouseListener(listener);
displayPanel.add(sp);
returnCodeLabel = new JLabel("");
returnCodeLabel.setBorder(BorderFactory.createTitledBorder("Return Code"));
displayPanel.add(returnCodeLabel, BorderLayout.SOUTH);
add(displayPanel);
}
public void actionPerformed(ActionEvent e)
{
int option = 0;
File selectedFile = null;
File[] selectedFiles = new File[0];
if (e.getActionCommand().equals("CLOSE"))
{
System.exit(0);
}
else if (e.getActionCommand().equals("OPEN"))
{
JFileChooser chooser = new JFileChooser();
chooser.setDragEnabled(true);
chooser.setMultiSelectionEnabled(true);
option = chooser.showOpenDialog(this);
selectedFiles = chooser.getSelectedFiles();
}
else if (e.getActionCommand().equals("SAVE"))
{
JFileChooser chooser = new JFileChooser();
option = chooser.showSaveDialog(this);
selectedFiles = chooser.getSelectedFiles();
}
// display the selection and return code
if (selectedFile != null)
selectedFileLabel.setText(selectedFile.toString());
else
selectedFileLabel.setText("null");
DefaultListModel listModel = new DefaultListModel();
for (int i =0; i < selectedFiles.length; i++)
listModel.addElement(selectedFiles[i]);
selectedFilesList.setModel(listModel);
returnCodeLabel.setText(Integer.toString(option));
}
public static void main(String[] args)
{
SwingUtilities.invokeLater
(new Runnable()
{
public void run()
{
FileChooserDemo app = new FileChooserDemo();
app.initFrameContent();
JFrame frame = new JFrame("LoquetUP");
frame.getContentPane().add(app);
frame.setDefaultCloseOperation(3);
frame.setSize(600,400);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
//frame.pack();
frame.setVisible(true);
}
});
}
}

This is my take on the idea. I've used the "traditional" drag and drop API in this example. It has some extra "paint" tweaks just to show off what you might be able to do.
This example doesn't scan folders dropped onto it, so any folder will only register as a single file, but I'm sure you can work it out
public class TestDragNDropFiles {
public static void main(String[] args) {
new TestDragNDropFiles();
}
public TestDragNDropFiles() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new DropPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class DropPane extends JPanel {
private DropTarget dropTarget;
private DropTargetHandler dropTargetHandler;
private Point dragPoint;
private boolean dragOver = false;
private BufferedImage target;
private JLabel message;
public DropPane() {
try {
target = ImageIO.read(new File("target.png"));
} catch (IOException ex) {
ex.printStackTrace();
}
setLayout(new GridBagLayout());
message = new JLabel();
message.setFont(message.getFont().deriveFont(Font.BOLD, 24));
add(message);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
protected DropTarget getMyDropTarget() {
if (dropTarget == null) {
dropTarget = new DropTarget(this, DnDConstants.ACTION_COPY_OR_MOVE, null);
}
return dropTarget;
}
protected DropTargetHandler getDropTargetHandler() {
if (dropTargetHandler == null) {
dropTargetHandler = new DropTargetHandler();
}
return dropTargetHandler;
}
#Override
public void addNotify() {
super.addNotify();
try {
getMyDropTarget().addDropTargetListener(getDropTargetHandler());
} catch (TooManyListenersException ex) {
ex.printStackTrace();
}
}
#Override
public void removeNotify() {
super.removeNotify();
getMyDropTarget().removeDropTargetListener(getDropTargetHandler());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (dragOver) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(new Color(0, 255, 0, 64));
g2d.fill(new Rectangle(getWidth(), getHeight()));
if (dragPoint != null && target != null) {
int x = dragPoint.x - 12;
int y = dragPoint.y - 12;
g2d.drawImage(target, x, y, this);
}
g2d.dispose();
}
}
protected void importFiles(final List files) {
Runnable run = new Runnable() {
#Override
public void run() {
message.setText("You dropped " + files.size() + " files");
}
};
SwingUtilities.invokeLater(run);
}
protected class DropTargetHandler implements DropTargetListener {
protected void processDrag(DropTargetDragEvent dtde) {
if (dtde.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
dtde.acceptDrag(DnDConstants.ACTION_COPY);
} else {
dtde.rejectDrag();
}
}
#Override
public void dragEnter(DropTargetDragEvent dtde) {
processDrag(dtde);
SwingUtilities.invokeLater(new DragUpdate(true, dtde.getLocation()));
repaint();
}
#Override
public void dragOver(DropTargetDragEvent dtde) {
processDrag(dtde);
SwingUtilities.invokeLater(new DragUpdate(true, dtde.getLocation()));
repaint();
}
#Override
public void dropActionChanged(DropTargetDragEvent dtde) {
}
#Override
public void dragExit(DropTargetEvent dte) {
SwingUtilities.invokeLater(new DragUpdate(false, null));
repaint();
}
#Override
public void drop(DropTargetDropEvent dtde) {
SwingUtilities.invokeLater(new DragUpdate(false, null));
Transferable transferable = dtde.getTransferable();
if (dtde.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
dtde.acceptDrop(dtde.getDropAction());
try {
List transferData = (List) transferable.getTransferData(DataFlavor.javaFileListFlavor);
if (transferData != null && transferData.size() > 0) {
importFiles(transferData);
dtde.dropComplete(true);
}
} catch (Exception ex) {
ex.printStackTrace();
}
} else {
dtde.rejectDrop();
}
}
}
public class DragUpdate implements Runnable {
private boolean dragOver;
private Point dragPoint;
public DragUpdate(boolean dragOver, Point dragPoint) {
this.dragOver = dragOver;
this.dragPoint = dragPoint;
}
#Override
public void run() {
DropPane.this.dragOver = dragOver;
DropPane.this.dragPoint = dragPoint;
DropPane.this.repaint();
}
}
}
}

You need to experiment with Drag & Drop and see exactly what flavors are available when you try to drag files. If you do this in your custom TransferHandler you'll be pleasantly surprised one Flavor is the DataFlavor.javaFileListFlavor, which indicates that the item can be used simply as a List. Try it and you'll see that it works!
Note on review of your posted code, I don't see any code for your attempt at using a TransferHandler, so it is hard to say what you could be doing wrong here.
Edit 1
You seem to be trying to use a MouseListener for your drag and drop, and I'm not familiar with this usage. Can you show a reference to a tutorial that tells you to do this?
Edit 2
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.io.File;
import java.io.IOException;
import java.util.List;
import javax.swing.*;
#SuppressWarnings("serial")
public class FileDragDemo extends JPanel {
private JList list = new JList();
public FileDragDemo() {
list.setDragEnabled(true);
list.setTransferHandler(new FileListTransferHandler(list));
add(new JScrollPane(list));
}
private static void createAndShowGui() {
FileDragDemo mainPanel = new FileDragDemo();
JFrame frame = new JFrame("FileDragDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
#SuppressWarnings("serial")
class FileListTransferHandler extends TransferHandler {
private JList list;
public FileListTransferHandler(JList list) {
this.list = list;
}
public int getSourceActions(JComponent c) {
return COPY_OR_MOVE;
}
public boolean canImport(TransferSupport ts) {
return ts.isDataFlavorSupported(DataFlavor.javaFileListFlavor);
}
public boolean importData(TransferSupport ts) {
try {
#SuppressWarnings("rawtypes")
List data = (List) ts.getTransferable().getTransferData(
DataFlavor.javaFileListFlavor);
if (data.size() < 1) {
return false;
}
DefaultListModel listModel = new DefaultListModel();
for (Object item : data) {
File file = (File) item;
listModel.addElement(file);
}
list.setModel(listModel);
return true;
} catch (UnsupportedFlavorException e) {
return false;
} catch (IOException e) {
return false;
}
}
}

Toggle read-only in Java

Is there a way to toggle a read-only mode so when you click any object in your window it simply returns what you clicked, ignoring the object's usual event handling? IE, while in this "read-only" mode, if you click on a Button, it simply returns the button, not actually pressing the button. Then I could do something like:
if ("thing pressed" == button) "do this";
else if ("thing pressed" == panel) "do that";
else "do nothing";
Here's my code, its a frame with 3 colored boxes. Clicking the 2nd box, the 3rd box, or the background will display a message. Clicking box 1 does nothing. I like using new mouse adapters so I want to do it this way.
Now what I want is when you click box 1, box 1 is treated as selected (if that helps you get the picture). Then if you click anywhere, including box 1 again, box 1 is deselected and nothing else (meaning that box 2, box 3. or the background's message will display). At that time, only if box 2 or 3 were clicked, they will still not display their normal message but a different message would be displayed.
I'm very sorry if I come off a little short.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Labels {
public static void main(String[] args) {
new Labels();
}
Square l1, l2, l3;
public Labels() {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
l1 = new Square();
l2 = new Square();
l3 = new Square();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(120, 150);
frame.setResizable(false);
panel.setVisible(true);
panel.setLayout(null);
l1.setLocation(5, 5);
l2.setLocation(5, 60);
l3.setLocation(60, 5);
l2.setColor("yellow");
l3.setColor("black");
l1.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
//do nothing
}
});
l2.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("Pushed label 2");
}
});
l3.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("Pushed label 3");
}
});
panel.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("pushed background");
}
});
frame.add(panel);
panel.add(l1);
panel.add(l2);
panel.add(l3);
}
class Square extends JLabel{
Color color = Color.blue;
public Square() {
// TODO Auto-generated constructor stub\
setVisible(true);
setSize(50,50);
}
public void paint(Graphics g) {
super.paint(g);
g.setColor(color);
g.fillRect(0, 0, 50, 50);
}
public void setColor(String color){
if (color == "white") this.color = Color.white;
else if (color == "black") this.color = Color.black;
else if (color == "yellow") this.color = Color.yellow;
else {
System.out.println("Invalid color");
return;
}
repaint();
}
}
}

Don't disable anything. Simply change the state of your class, perhaps by using a few boolean flag variables/fields and change these flags depending on what is pressed.
So have boolean fields called label1PressedLast, label2PressedLast, and label3PressedLast or something similar, and when a label is pressed, check the states of all other flags and have your program's behavior change depending on the state of these flags and the label that was just pressed. Then set all flags to false except for the one corresponding to the label that was just pressed.
For example, this little program reacts only if the first and then the third JLabel have been pressed:
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;
public class FlagEg extends JPanel {
private static final int LABEL_COUNT = 3;
private JLabel[] labels = new JLabel[LABEL_COUNT];
private boolean[] flags = new boolean[LABEL_COUNT];
public FlagEg() {
setLayout(new GridLayout(1, 0, 20, 0));
setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
// panel mouse listener
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent arg0) {
inactivateAll();
}
});
MouseListener labelsMouseListener = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent mouseEvt) {
myMousePressed(mouseEvt);
}
};
// create JLabels and add MouseListener
for (int i = 0; i < labels.length; i++) {
labels[i] = new JLabel("Label " + (i + 1));
labels[i].addMouseListener(labelsMouseListener);
labels[i].setOpaque(true);
labels[i].setBorder(BorderFactory.createLineBorder(Color.black));
add(labels[i]);
}
}
private void inactivateAll() {
for (int i = 0; i < labels.length; i++) {
labels[i].setBackground(null);
flags[i] = false;
}
}
private void myMousePressed(MouseEvent mouseEvt) {
JLabel label = (JLabel) mouseEvt.getSource();
// which label was pressed?
int index = -1;
for (int i = 0; i < labels.length; i++) {
if (label == labels[i]) {
index = i;
}
}
// check if first label and then third pressed:
if (flags[0] && index == 2) {
System.out.println("first and then third label pressed!");
}
// reset all labels and flags to initial state
inactivateAll();
// set pressed label background color and set flag of label just pressed
labels[index].setBackground(Color.pink);
flags[index] = true;
}
private static void createAndShowGui() {
FlagEg mainPanel = new FlagEg();
JFrame frame = new JFrame("Flag Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Logic iteration two: only label 1 is the "primer" JLabel. This is actually easier to implement, because now you only need one boolean flag, that representing label 1 being pressed:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class FlagEg2 extends JPanel {
private static final int LABEL_COUNT = 3;
private JLabel[] labels = new JLabel[LABEL_COUNT];
private boolean label1Flag = false;
public FlagEg2() {
setLayout(new GridLayout(1, 0, 20, 0));
setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
// panel mouse listener
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent arg0) {
inactivateAll();
}
});
MouseListener labelsMouseListener = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent mouseEvt) {
myMousePressed(mouseEvt);
}
};
// create JLabels and add MouseListener
for (int i = 0; i < labels.length; i++) {
labels[i] = new JLabel("Label " + (i + 1));
labels[i].addMouseListener(labelsMouseListener);
labels[i].setOpaque(true);
labels[i].setBorder(BorderFactory.createLineBorder(Color.black));
add(labels[i]);
}
}
private void inactivateAll() {
for (int i = 0; i < labels.length; i++) {
labels[i].setBackground(null);
label1Flag = false;
}
}
private void myMousePressed(MouseEvent mouseEvt) {
JLabel label = (JLabel) mouseEvt.getSource();
// which label was pressed?
int index = -1;
for (int i = 0; i < labels.length; i++) {
if (label == labels[i]) {
index = i;
}
}
if (label1Flag) {
if (index == 1) {
System.out.println("Label 1 and label 2 pressed");
} else if (index == 2) {
System.out.println("Label 1 and label 3 pressed");
}
}
// reset all labels and flags to initial state
inactivateAll();
// if label1, then activate it
if (index == 0) {
labels[0].setBackground(Color.pink);
label1Flag = true;
}
}
private static void createAndShowGui() {
FlagEg2 mainPanel = new FlagEg2();
JFrame frame = new JFrame("Flag Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

package javaapplication6;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
/**
*
* #author Jan Vorcak <vorcak#mail.muni.cz>
*/
public class Main {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
MouseListener listener = new MouseAdapter() {
private int count = 0;
#Override
public void mouseClicked(MouseEvent e) {
if(e.getComponent() instanceof JLabel) {
count++;
if (count >= 2) {
System.out.println("clicked 2 times on labels");
count = 0;
}
} else {
count = 0;
}
}
};
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JLabel l1 = new JLabel("Label 1");
JLabel l2 = new JLabel("Label 2");
JLabel l3 = new JLabel("Label 3");
l1.addMouseListener(listener);
l2.addMouseListener(listener);
l3.addMouseListener(listener);
frame.addMouseListener(listener); // or panel.addMouseListener(listener);
panel.add(l1);
panel.add(l2);
panel.add(l3);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
}

You could want to create a listener that do the job for using the putClientProperty method of JComponent.
public class JComponentClickCountListener extends MouseAdapter {
private final Integer ONE = 1;
#Override
public void mouseClicked(MouseEvent e) {
if (e.getComponent() instanceof JComponent) {
JComponent jComponent = (JComponent) e.getComponent();
Object property = jComponent.getClientProperty(JComponentClickCountListener.class);
if (property instanceof Number) {
property = ONE + ((Number) property).intValue();
}
else {
property = ONE;
}
jComponent.putClientProperty(JComponentClickCountListener.class, property);
}
}
}
Then in your code you can decide to have a single instace of that class for all of your components or create a new one each time.
This could give you the advantage of using the propertyChangeListener for future actions.
PS.
The code example do not represent all logic for OP question but i could by used as solid base. Later on i will try to update it. To cover that.
EDIT2:
I think that you should separate the logic, of selection and action over selected items. Then the task is divided into two tasks. First is the possibility to store the information about it state, clicked active, clicked again inactive. The second tasks it to operate on that status when a jComponent status was changed.
This is an simple example that i wrote, the functionality is to highlight the background of labels when the are selected and remove it when it was clicked again or the panel was clicked remove all selections.
This example is divided to three elements Enum, Iterface and class that manage the logic of selection
Enum - we store the possible statuses and a property key.
public enum JComponentActivationStatus {
NONE,
ACTIVE,
INACTIVE;
public static final String PROPERTY_KEY = JComponentActivationStatus.class.getCanonicalName();
}
Interface - provide a delegate for action to be taken when jcomponenet status change.
public abstract interface JComponenetActivationStatusChangeAction<T extends JComponent> {
public abstract void onActivation(T object);
public abstract void onDeactivation(T object);
}
Class - This class mange the status logic of jcomponents.
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.JComponent;
public class JComponenetActivationManager {
public static <T extends JComponent> T addMouseStatusControl(T jComponent) {
jComponent.addMouseListener(new JComponentMouseStatusModyfier());
return jComponent;
}
public static <T extends JComponent> T addActivationStatusChangeAction(T jComponenet, JComponenetActivationStatusChangeAction<T> statusChangeAction) {
jComponenet.addPropertyChangeListener(craeteJCompositeActivationStatusChangeListener(statusChangeAction));
return jComponenet;
}
public static <T extends JComponent> PropertyChangeListener craeteJCompositeActivationStatusChangeListener(JComponenetActivationStatusChangeAction<T> action) {
return new JComponentStatusPropertyChangeListener<T>(action);
}
/**
* Class that set the status for the JComponet after doubClicl
*/
private final static class JComponentMouseStatusModyfier extends MouseAdapter {
#Override
public void mouseClicked(MouseEvent e) {
if(e.getComponent() instanceof JComponent) {
JComponent jComponent = (JComponent) e.getComponent();
Object propertyValue = jComponent.getClientProperty(JComponentActivationStatus.PROPERTY_KEY);
if(JComponentActivationStatus.ACTIVE.equals(propertyValue)) { //We check that the ACTIVE status is already selected, if so we inactive.
propertyValue = JComponentActivationStatus.INACTIVE; //If so we inactive it.
} else {
propertyValue = JComponentActivationStatus.ACTIVE; // Otherwise we set it as active
}
jComponent.putClientProperty(JComponentActivationStatus.PROPERTY_KEY, propertyValue); // We use the property key form status
}
}
}
/**
* Help class that fire the actions after status is changed
*/
private static final class JComponentStatusPropertyChangeListener<T extends JComponent> implements PropertyChangeListener {
private final JComponenetActivationStatusChangeAction<T> statusChangeAction;
/**
*
*/
public JComponentStatusPropertyChangeListener(JComponenetActivationStatusChangeAction<T> statusChangeAction) {
if(statusChangeAction == null) {
throw new IllegalArgumentException("action can not be null at this point");
}
this.statusChangeAction = statusChangeAction;
}
#Override
public void propertyChange(PropertyChangeEvent evt) {
if(JComponentActivationStatus.PROPERTY_KEY.equals(evt.getPropertyName())) {
if(JComponentActivationStatus.ACTIVE.equals(evt.getNewValue())) {
statusChangeAction.onActivation((T) evt.getSource());
}
if(JComponentActivationStatus.INACTIVE.equals(evt.getNewValue())){
statusChangeAction.onDeactivation((T) evt.getSource());
}
}
}
}
}
That class contain two public static method, that allow the developer to add the functionality to mange status to any jComponent object, add subscribe the action handler if any change occur.
At the end we have the main method that test our solution
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JLabel l1 = new JLabel("Label 1");
JLabel l2 = new JLabel("Label 2");
JLabel l3 = new JLabel("Label 3");
panel.setBackground(Color.CYAN);
addMouseStatusControl(panel);
addMouseStatusControl(l1);
addMouseStatusControl(l2);
addMouseStatusControl(l3);
JComponenetActivationStatusChangeAction<JLabel> activeBackground = new JComponenetActivationStatusChangeAction<JLabel>() {
#Override
public void onActivation(JLabel object) {
object.setOpaque(true);
object.setBackground(Color.YELLOW);
}
#Override
public void onDeactivation(JLabel object) {
object.setOpaque(false);
object.setBackground(object.getParent().getBackground());
}
};
JComponenetActivationStatusChangeAction<JPanel> deactivateChildrens = new JComponenetActivationStatusChangeAction<JPanel>() {
#Override
public void onDeactivation(JPanel object) {
}
#Override
public void onActivation(JPanel object) {
for(Component component : object.getComponents()) {
if(component instanceof JComponent) {
((JComponent) component).putClientProperty(JComponentActivationStatus.PROPERTY_KEY,JComponentActivationStatus.INACTIVE);
}
}
}
};
addActivationStatusChangeAction(l1, activeBackground);
addActivationStatusChangeAction(l2, activeBackground);
addActivationStatusChangeAction(l3, activeBackground);
addActivationStatusChangeAction(panel, deactivateChildrens);
panel.add(l1);
panel.add(l2);
panel.add(l3);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
The solution is very flexible and extendable in case you will need to add more labels.
The example is for those that want to learn. Any comment would be appreciate.