javaswingjframemouse-listenerscomponentlistener

Swing: resizing a JFrame like Frames in Linux e.g


I would like to know if theres a possibility to implement the resizing of a JFrame in that manner, that it's been resized like for example the standart windows in linux. To be more precise: If the user starts do drag, only the future size if the window will be previewed, while the original content is not resized. As soon as the user releases the mouse, the Frame resizes to that size. In images:

(1) state before resizing

enter image description here

(2) user starts to drage (at the red circle)

enter image description here

(3) user releases the mouse, the frame gets resized

enter image description here

Is it possible to realize that in Java Swing?

EDIT:

As this program one day should run also in lower Java RE as the 7, I tried to combine mKorbel suggestions with and the suggestion in the comment with the translucend Frame. The result is close to the goal, except that

I think the first point is resolvable by a combination of the code and a MouseListener, something like if mouseReleased(), then resize . Here is the code, feel free to try it. For further suggestions I'm still happy about any suggestions.

The code is a slightly modification of the GradientTranslucentWindowDemo.java from the Java Tutorials. I hope it's permitted to post it here, otherwise please indicate me any violation against copyright causas. The black JPanel is supposed to be the content of the application, where as the contentPane stays invisible.

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.beans.PropertyChangeListener;

import javax.swing.*;
import static java.awt.GraphicsDevice.WindowTranslucency.*;

public class GroundFrame extends JFrame {

    Timer timer;
    JPanel panel2;

    public GroundFrame() {
        super("GradientTranslucentWindow");

        setBackground(new Color(0,0,0,0));
        setSize(new Dimension(300,200));
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel panel = new JPanel() {
        panel.setBackground(new Color(0,0,0,0));
        setContentPane(panel);

        setLayout(null);
        panel2 = new JPanel();
        panel2.setBackground(Color.black);
        panel2.setBounds(0,0,getContentPane().getWidth(), getContentPane().getHeight());
        getContentPane().add(panel2);

        addComponentListener(new ComponentListener() {

            @Override
            public void componentShown(ComponentEvent e) {}

            @Override
            public void componentResized(ComponentEvent e) {
                timer = new Timer(50, new Action() {

                    @Override
                    public void actionPerformed(ActionEvent e) {
                        if(timer.isRunning()){

                        }else{
                            resizePanel(getContentPane().getSize());
                        }
                    }

                    @Override
                    public void setEnabled(boolean b) {}

                    @Override
                    public void removePropertyChangeListener(PropertyChangeListener listener) {}

                    @Override
                    public void putValue(String key, Object value) {}

                    @Override
                    public boolean isEnabled() {return false;}

                    @Override
                    public Object getValue(String key) {return null;}

                    @Override
                    public void addPropertyChangeListener(PropertyChangeListener listener) {}
                });
                timer.setRepeats(false);
                timer.start();

            }

            @Override
            public void componentMoved(ComponentEvent e) {}

            @Override
            public void componentHidden(ComponentEvent e) {}
        });
    }

    public void resizePanel(Dimension dim){
        panel2.setBounds(0,0,dim.width, dim.height);
        repaint();
    }

    public static void main(String[] args) {
        GraphicsEnvironment ge =
            GraphicsEnvironment.getLocalGraphicsEnvironment();
        GraphicsDevice gd = ge.getDefaultScreenDevice();
        boolean isPerPixelTranslucencySupported =
            gd.isWindowTranslucencySupported(PERPIXEL_TRANSLUCENT);

        if (!isPerPixelTranslucencySupported) {
            System.out.println(
                "Per-pixel translucency is not supported");
                System.exit(0);
        }

        JFrame.setDefaultLookAndFeelDecorated(true);

        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                GroundFrame gtw = new GroundFrame();
                gtw.setVisible(true);
            }
        });
    }
}

Solution

  • +1 to mKorbel and Denis Tulskiy's answers.

    I did a sort of abstract solution which might be of help. It supports resizing (increasing and decreasing height and width) of JFrame from all four sides of the JFrame (NORTH, EAST, SOUTH and WEST) it also can be re-sized by width and height simultaneously when mouse is moved to one of the for corners.

    Basically what I did was:

    Check out this example I made:

    import java.awt.Cursor;
    import java.awt.Dimension;
    import java.awt.event.MouseAdapter;
    import java.awt.event.MouseEvent;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    
    public class JFrameSizeAfterDrag extends JFrame {
    
        //direction holds the position of drag
        private int w = 0, h = 0, direction, startX = 0, startY = 0;
    
        public JFrameSizeAfterDrag() {
            setResizable(false);
            setDefaultCloseOperation(EXIT_ON_CLOSE);
    
            addMouseListener(new MouseAdapter() {
                //so we can see if from where the user clikced is he increasing or decraesing size
                @Override
                public void mousePressed(MouseEvent me) {
                    super.mouseClicked(me);
                    startX = me.getX();
                    startY = me.getY();
                    System.out.println("Clicked: " + startX + "," + startY);
                }
    
                //when the mouse is relaeased set size
                @Override
                public void mouseReleased(MouseEvent me) {
                    super.mouseReleased(me);
                    System.out.println("Mouse released");
                    if (direction == 1 || direction == 2 || direction == 5 || direction == 6) {
                        setSize(w, h);
                    } else {//this should move x and y by as much as the mouse moved then use setBounds(x,y,w,h);
                        setBounds(getX() - (startX - me.getX()), getY() - (startY - me.getY()), w, h);
                    }
                    validate();
                }
            });
    
            addMouseMotionListener(new MouseAdapter() {
                private boolean canResize;
    
                //while dragging check direction of drag
                @Override
                public void mouseDragged(MouseEvent me) {
                    super.mouseDragged(me);
                    System.out.println("Dragging:" + me.getX() + "," + me.getY());
                    if (canResize && direction == 1) {//frame height  change
                        if (startY > me.getY()) {//decrease in height
                            h -= 4;
                        } else {//increase in height
                            h += 4;
                        }
                    } else if (canResize && direction == 2) {//frame width  change
                        if (startX > me.getX()) {//decrease in width
                            w -= 4;
                        } else {//increase in width
                            w += 4;
                        }
                    } else if (canResize && direction == 3) {//frame height  change
                        if (startX > me.getX()) {//decrease in width
                            w += 4;
                        } else {//increase in width
                            w -= 4;
                        }
                    } else if (canResize && direction == 4) {//frame width  change
                        if (startY > me.getY()) {//decrease in height
                            h += 4;
                        } else {//increase in height
                            h -= 4;
                        }
                    } else if (canResize && direction == 5) {//frame width and height  change bottom right
                        if (startY > me.getY() && startX > me.getX()) {//increase in height and width
                            h -= 4;
                            w -= 4;
                        } else {//decrease in height and with
                            h += 4;
                            w += 4;
                        }
                    } /* Windows dont usually support reszing from top but if you want :) uncomment code in mouseMoved(..) also
                     else if (canResize && direction == 6) {//frame width and height  change top left
                     if (startY > me.getY() && startX > me.getX()) {//decrease in height and with
                     h += 4;
                     w += 4;
                     } else {//increase in height and width
                     h -= 4;
                     w -= 4;
                     }
                     } else if (canResize && direction == 8) {//frame width and height  change top right
                     if (startY > me.getY() && startX > me.getX()) {//increase in height and width
                     h -= 4;
                     w -= 4;
                     } else {//decrease in height and with
                     h += 4;
                     w += 4;
                     }
                     }
                     */ else if (canResize && direction == 7) {//frame width and height  change bottom left
                        if (startY > me.getY() && startX > me.getX()) {//increase in height and width
                            h -= 4;
                            w -= 4;
                        } else {//decrease in height and with
                            h += 4;
                            w += 4;
                        }
                    }
                }
    
                @Override
                public void mouseMoved(MouseEvent me) {
                    super.mouseMoved(me);
                    if (me.getY() >= getHeight() - 10 && me.getX() >= getWidth() - 10) {//close to bottom and right side of frame show south east cursor and allow height witdh simaltneous increase/decrease
                        //System.out.println("resize allowed..");
                        canResize = true;
                        setCursor(Cursor.getPredefinedCursor(Cursor.SE_RESIZE_CURSOR));
                        direction = 5;
                    } /*Windows dont usually support reszing from top but if you want :) uncomment code in mouseDragged(..) too
                     else if (me.getY() <= 28 && me.getX() <= 28) {//close to top side and left side of frame show north west cursor and only allow increase/decrease in width and height simultaneosly
                     //System.out.println("resize allowed..");
                     canResize = true;
                     setCursor(Cursor.getPredefinedCursor(Cursor.NW_RESIZE_CURSOR));
                     direction = 6;
                     }  else if (me.getY() <= 28 && me.getX() >= getWidth() - 10) {//close to top and right side of frame show north east cursor and only allow increase/decrease in width and height simultaneosly
                     //System.out.println("resize allowed..");
                     canResize = true;
                     setCursor(Cursor.getPredefinedCursor(Cursor.NE_RESIZE_CURSOR));
                     direction = 8;
                     } 
                     */ else if (me.getY() >= getHeight() - 10 && me.getX() <= 10) {//close to bottom side and left side of frame show north west cursor and only allow increase/decrease in width and height simultaneosly
                        //System.out.println("resize allowed..");
                        canResize = true;
                        setCursor(Cursor.getPredefinedCursor(Cursor.SW_RESIZE_CURSOR));
                        direction = 7;
                    } else if (me.getY() >= getHeight() - 10) {//close to bottom of frame show south resize cursor and only allow increase height
                        //System.out.println("resize allowed");
                        canResize = true;
                        setCursor(Cursor.getPredefinedCursor(Cursor.S_RESIZE_CURSOR));
                        direction = 1;
                    } else if (me.getX() >= getWidth() - 10) {//close to right side of frame show east cursor and only allow increase width
                        //System.out.println("resize allowed");
                        canResize = true;
                        setCursor(Cursor.getPredefinedCursor(Cursor.E_RESIZE_CURSOR));
                        direction = 2;
                    } else if (me.getX() <= 10) {//close to left side of frame show east cursor and only allow increase width
                        //System.out.println("resize allowed");
                        canResize = true;
                        setCursor(Cursor.getPredefinedCursor(Cursor.W_RESIZE_CURSOR));
                        direction = 3;
                    } else if (me.getY() <= 28) {//close to top side of frame show east cursor and only allow increase height
                        // System.out.println("resize allowed..");
                        canResize = true;
                        setCursor(Cursor.getPredefinedCursor(Cursor.N_RESIZE_CURSOR));
                        direction = 4;
                    } else {
                        canResize = false;
                        setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
                        // System.out.println("resize not allowed");
                    }
                }
            });
    
            //just so GUI is visible and not small
            add(new JPanel() {
                @Override
                public Dimension getPreferredSize() {
                    return new Dimension(200, 200);
                }
            });
    
            pack();
            setVisible(true);
        }
    
        @Override
        public void setVisible(boolean bln) {
            super.setVisible(bln);
            w = getWidth();
            h = getHeight();
        }
    
        public static void main(String[] args) {
    
            /**
             * Create GUI and components on Event-Dispatch-Thread
             */
            javax.swing.SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                    new JFrameSizeAfterDrag();
                }
            });
        }
    }
    

    UPDATE:

    Great example you made I fixed the code by adding MouseAdapter which overrides mouseReleased(..) which calls resizePanel(...) when mouseReleased(..)

    see here for the fixed code (also fixed a few minor things like added ComponentAdapter instead of ComponentListener and AbstractAction instead of Action):

    import java.awt.*;
    import static java.awt.GraphicsDevice.WindowTranslucency.*;
    import java.awt.event.ActionEvent;
    import java.awt.event.ComponentAdapter;
    import java.awt.event.ComponentEvent;
    import java.awt.event.MouseAdapter;
    import java.awt.event.MouseEvent;
    import javax.swing.*;
    
    public class JFrameSizeAfterDrag2 extends JFrame {
    
        private Timer timer;
        private JPanel panel2;
        boolean canResize = true,firstTime = true;
    
    
        public JFrameSizeAfterDrag2() {
            super("GradientTranslucentWindow");
    
            setBackground(new Color(0, 0, 0, 0));
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
            setContentPane(new JPanel(null) {//contentpane layout is null only
                @Override
                protected void paintComponent(Graphics g) {
                    Paint p = new GradientPaint(0.0f, 0.0f, new Color(0, 0, 0, 0), 0.0f, getHeight(), new Color(0, 0, 0, 0), true);
                    Graphics2D g2d = (Graphics2D) g;
                    g2d.setPaint(p);
                    g2d.fillRect(0, 0, getWidth(), getHeight());
                }
    
                @Override
                public Dimension getPreferredSize() {
                    return new Dimension(300, 300);
                }
            });
    
            panel2 = new JPanel();
            panel2.setBackground(Color.black);
            getContentPane().add(panel2);
    
            addMouseListener(new MouseAdapter() {
                @Override
                public void mouseReleased(MouseEvent me) {
                    super.mouseReleased(me);
                    if (canResize) {
                        resizePanel(getContentPane().getSize());
                    }
                }
            });
    
            addComponentListener(new ComponentAdapter() {
    
                @Override
                public void componentResized(ComponentEvent e) {
                    timer = new Timer(50, new AbstractAction() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            if (timer.isRunning()) {
                                canResize = false;
                            } else {
                                canResize = true;
                                if (firstTime == true) {
                                    firstTime = false;
                                    resizePanel(getContentPane().getSize());
                                }
                            }
                        }
                    });
                    timer.setRepeats(false);
                    timer.start();
    
                }
            });
            pack();
        }
    
        public void resizePanel(Dimension dim) {
            panel2.setBounds(0, 0, dim.width, dim.height);
            revalidate();
        }
    
        public static void main(String[] args) {
            GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
            GraphicsDevice gd = ge.getDefaultScreenDevice();
            boolean isPerPixelTranslucencySupported = gd.isWindowTranslucencySupported(PERPIXEL_TRANSLUCENT);
    
            if (!isPerPixelTranslucencySupported) {
                System.out.println("Per-pixel translucency is not supported");
                System.exit(0);
            }
    
            JFrame.setDefaultLookAndFeelDecorated(true);
    
            SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                    JFrameSizeAfterDrag2 gtw = new JFrameSizeAfterDrag2();
                    gtw.setVisible(true);
                }
            });
        }
    }