Develop Reference

Java drawstring working fine in earlier part of the code to count points but doesn't work when to show game over [duplicate]

After learning that dispose() should be called on Graphics/Graphics2D object after use, I went about changing my game to incorporate this.
When I added g2d.dispose() in overridden paintComponent(Graphics g) of JPanel, my components which I added (extensions of JLabel class) where not rendered I was able to still click on them etc but they would not be painted.
I tested with a normal JLabel and JButton with same effect (though JButton is rendered when mouse is over it).
So my question is why does this happen?
Here is an SSCCE to demonstrate:
after uncommenting call to dispose() in paintComponent of MainMenuPanel class:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.net.URL;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
public Test() {
try {
initComponents();
} catch (Exception ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Test();
}
});
}
private void initComponents() throws Exception {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
MainMenuPanel mmp = new MainMenuPanel();
frame.add(mmp);
frame.pack();
frame.setVisible(true);
}
}
class MainMenuPanel extends JPanel {
//create labels for Main Menu
private PopUpJLabel versusesModeLabel;
private PopUpJLabel singlePlayerModeLabel;
private PopUpJLabel optionsLabel;
private PopUpJLabel helpLabel;
private PopUpJLabel aboutLabel;
//create variable to hold background
private Image background;
private Dimension preferredDimensions;
public static String gameType;
public static final String SINGLE_PLAYER = "Single Player", VERSUS_MODE = "VS Mode";
/**
* Default constructor to initialize double buffered JPanel with
* GridBagLayout
*/
public MainMenuPanel() {
super(new GridBagLayout(), true);
try {
initComponents();
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, "Could not load main menu background!", "Main Menu Error: 0x004", JOptionPane.ERROR_MESSAGE);
System.exit(4);
}
}
/*
* Create JPanel and its components
*/
private void initComponents() throws Exception {
//set prefered size of JPanel
preferredDimensions = new Dimension(800, 600);
background = scaleImage(800, 600, ImageIO.read(new URL("http://photos.appleinsider.com/12.08.30-Java.jpg")));
//create label instances
singlePlayerModeLabel = new PopUpJLabel("Single Player Mode");
singlePlayerModeLabel.setEnabled(false);
versusesModeLabel = new PopUpJLabel("Versus Mode");
optionsLabel = new PopUpJLabel("Options");
helpLabel = new PopUpJLabel("Help");
aboutLabel = new PopUpJLabel("About");
//create new constraints for gridbag
GridBagConstraints gc = new GridBagConstraints();
gc.fill = GridBagConstraints.HORIZONTAL;
gc.ipady = 50;//vertical spacing
//add newGameLabel to panel with constraints
gc.gridx = 0;
gc.gridy = 0;
add(singlePlayerModeLabel, gc);
gc.gridy = 1;
add(versusesModeLabel, gc);
//add optionsLabel to panel with constraints (x is the same)
gc.gridy = 2;
add(optionsLabel, gc);
//add helpLabel to panel with constraints (x is the same)
gc.gridy = 3;
add(helpLabel, gc);
//add aboutLabel to panel with constraints (x is the same)
gc.gridy = 4;
add(aboutLabel, gc);
}
public static BufferedImage scaleImage(int w, int h, BufferedImage img) throws Exception {
BufferedImage bi;
//bi = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
bi = new BufferedImage(w, h, img.getType());
Graphics2D g2d = (Graphics2D) bi.createGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.addRenderingHints(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY));
g2d.drawImage(img, 0, 0, w, h, null);
g2d.dispose();
return bi;
}
/*
* Will return the preffered size of JPanel
*/
#Override
public Dimension getPreferredSize() {
return preferredDimensions;
}
/*
* Will draw the background to JPanel with anti-aliasing on and quality rendering
*/
#Override
protected void paintComponent(Graphics grphcs) {
super.paintComponent(grphcs);
//convert graphics object to graphics2d object
Graphics2D g2d = (Graphics2D) grphcs;
//set anti-aliasing on and rendering etc
//GamePanel.applyRenderHints(g2d);
//draw the image as the background
g2d.drawImage(background, 0, 0, null);
//g2d.dispose();//if I uncomment this no LAbels will be shown
}
}
class PopUpJLabel extends JLabel {
public final static Font defaultFont = new Font("Arial", Font.PLAIN, 50);
public final static Font hoverFont = new Font("Arial", Font.BOLD, 70);
PopUpJLabel(String text) {
super(text);
setHorizontalAlignment(JLabel.CENTER);
setForeground(Color.ORANGE);
setFont(defaultFont);
//allow component to be focusable
setFocusable(true);
//add focus adapter to change fints when focus is gained or lost (used for transversing labels with keys)
addFocusListener(new FocusAdapter() {
#Override
public void focusGained(FocusEvent fe) {
super.focusGained(fe);
if (isEnabled()) {
setFont(getHoverFont());
}
}
#Override
public void focusLost(FocusEvent fe) {
super.focusLost(fe);
setFont(getDefaultFont());
}
});
addMouseListener(new MouseAdapter() {
#Override
public void mouseEntered(MouseEvent me) {
super.mouseEntered(me);
if (isEnabled()) {
setFont(getHoverFont());
}
//call for focus mouse is over this component
requestFocusInWindow();
}
});
}
Font getDefaultFont() {
return defaultFont;
}
Font getHoverFont() {
return hoverFont;
}
}

The thing is that the Graphics context you are using in paintComponent is created and provided by the caller (the framework), which is also responsible for disposing of it.
You only need to dispose of Graphics when you actually create it yourself (for example by calling Component.getGraphics()). In your case, you're not creating it, you're just casting it, so do not call dispose in this case.

Because .dispose() releases your resources. Yes, everything.

JTabbedPane and it's tab transparency won't work

I've done several inspection and done research on how to make a single panel transparent so that the image underneath it will show but has been unsuccessful with panels on a JTabbedPane. I have setOpaque(false) and setBackground(new Color(0,0,0,20)) on both the panels of the JTabbedPane and also did the same on the JTabbedPane itself. However, I still can't get the image on the back of the tabbed pane to show. What else am I missing here?
tabbePane.java
package tabbedpanetransparencypractice;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.*;
public class tabbedPane extends JTabbedPane{
JPanel tab1panel = new JPanel();
JPanel tab2panel = new JPanel();
public tabbedPane(){
this.setPreferredSize(new Dimension(400,400));
this.setBackground(new Color(0,0,0,20));
this.setOpaque(false);
tab1panel.setBackground(new Color(0,0,0,20));
tab2panel.setBackground(new Color(0,0,0,20));
tab1panel.setOpaque(false);
tab2panel.setOpaque(false);
this.addTab("Tab 1", tab1panel);
this.addTab("Tab 2", tab2panel);
}
}
topPanel.java
package tabbedpanetransparencypractice;
import javax.swing.*;
import java.awt.*;
public class topPanel extends JPanel{
Image myBG = new ImageIcon(getClass().getClassLoader().getResource("Assets/loginBg.jpg")).getImage();
#Override
public void paintComponent(Graphics g){
g.drawImage(myBG,0,0,getWidth(),getHeight(),this);
}
public topPanel(){
addTabbedPane();
}
public void addTabbedPane(){
tabbedPane tabbedpane = new tabbedPane();
this.add(tabbedpane);
}
}
frame.java
package tabbedpanetransparencypractice;
import java.awt.Dimension;
import javax.swing.*;
public class frame extends JFrame{
topPanel myPanel = new topPanel();
public frame(){
this.setPreferredSize(new Dimension(600,600));
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
this.pack();
this.setLocationRelativeTo(null);
addComponents();
}
final void addComponents(){
this.setContentPane(myPanel);
}
}
main.java
package tabbedpanetransparencypractice;
public class main {
public static void main(String[] args) {
frame myFrame = new frame();
}
}
This is the output I get (I want the tab1 and tab2 to be transparent to reveal the bg image underneath)
I'd appreciate any help. Thanks.

First, Swing DOES NOT know how to deal with component's whose background colors are alpha based but which are opaque. Swing only knows how to deal with fully opaque and fully transparent components.
Using alpha based colors will generate weird and random paint artefacts. The simple answer is, you should never apply a alpha based color to a component's background (the only exception is JFrame - thanks Sun :P)
The primary solution is, fake it.
That is, make the component transparent (setOpaque(false)) and paint the background at a reduced alpha level. You can then use a alpha based color (because the component is no longer reliant on the color, as it's transparent), but I tend to just use a AlphaComposite as it's generally easier to control and manipulate.
import java.awt.AlphaComposite;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagLayout;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
BackgroundPane bp = new BackgroundPane();
bp.setLayout(new BorderLayout());
bp.setBorder(new EmptyBorder(20, 20, 20, 20));
SeeThroughTabbedPane tp = new SeeThroughTabbedPane();
tp.setAlpha(0.5f);
tp.addTab("Tab 1", new TestPane("I be see through"));
tp.addTab("Tab 2", new TestPane("But you can't see me"));
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(bp);
frame.add(tp);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane(String text) {
setOpaque(false);
setLayout(new GridBagLayout());
JLabel label = new JLabel(text);
label.setForeground(Color.WHITE);
add(label);
}
}
public class BackgroundPane extends JPanel {
private BufferedImage bg;
public BackgroundPane() {
try {
bg = ImageIO.read(new File("/Volumes/Disk02/Dropbox/MegaTokyo/megatokyo_omnibus_1_3_cover_by_fredrin-d4oupef 50%.jpg"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
public Dimension getPreferredSize() {
return bg == null ? new Dimension(200, 200) : new Dimension(bg.getWidth(), bg.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (bg != null) {
Graphics2D g2d = (Graphics2D) g.create();
int x = (getWidth() - bg.getWidth()) / 2;
int y = (getHeight() - bg.getHeight()) / 2;
g2d.drawImage(bg, x, y, this);
g2d.dispose();
}
}
}
public class SeeThroughTabbedPane extends JTabbedPane {
private float alpha;
public SeeThroughTabbedPane() {
setOpaque(false);
setAlpha(1f);
}
public void setAlpha(float value) {
if (alpha != value) {
float old = alpha;
this.alpha = value;
firePropertyChange("alpha", old, alpha);
repaint();
}
}
public float getAlpha() {
return alpha;
}
#Override
protected void paintComponent(Graphics g) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(getBackground());
g2d.setComposite(AlphaComposite.SrcOver.derive(getAlpha()));
g2d.fillRect(0, 0, getWidth(), getHeight());
g2d.dispose();
super.paintComponent(g);
}
}
}
Remember, anything you added to the JTabbedPane which is still opaque will remain so, not in my TestPane's constructor, I set the panel's opaque state to false
You might also like to take a look at Painting in AWT and Swing and Performing Custom Painting

You might be able to use UIManager.put("TabbedPane.contentAreaColor", new Color(255, 255, 0, 100));
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TransparentTabbedPaneTest {
public JComponent makeUI() {
Color bgc = new Color(110, 110, 0, 100);
Color fgc = new Color(255, 255, 0, 100);
UIManager.put("TabbedPane.shadow", fgc);
UIManager.put("TabbedPane.darkShadow", fgc);
UIManager.put("TabbedPane.light", fgc);
UIManager.put("TabbedPane.highlight", fgc);
UIManager.put("TabbedPane.tabAreaBackground", fgc);
UIManager.put("TabbedPane.unselectedBackground", fgc);
UIManager.put("TabbedPane.background", bgc);
UIManager.put("TabbedPane.foreground", Color.WHITE);
UIManager.put("TabbedPane.focus", fgc);
UIManager.put("TabbedPane.contentAreaColor", fgc);
UIManager.put("TabbedPane.selected", fgc);
UIManager.put("TabbedPane.selectHighlight", fgc);
UIManager.put("TabbedPane.borderHightlightColor", fgc);
JTabbedPane tabs = new JTabbedPane();
JPanel tab1panel = new JPanel();
tab1panel.setBackground(new Color(0, 220, 220, 50));
JPanel tab2panel = new JPanel();
tab2panel.setBackground(new Color(220, 0, 0, 50));
JPanel tab3panel = new JPanel();
tab3panel.setBackground(new Color(0, 0, 220, 50));
JCheckBox cb = new JCheckBox("setOpaque(false)");
cb.setOpaque(false);
tab3panel.add(cb);
tab3panel.add(new JCheckBox("setOpaque(true)"));
tabs.addTab("Tab 1", tab1panel);
tabs.addTab("Tab 2", tab2panel);
tabs.addTab("Tab 3", new AlphaContainer(tab3panel));
JPanel p = new JPanel(new BorderLayout()) {
private Image myBG = new ImageIcon(getClass().getResource("test.png")).getImage();
#Override public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(myBG, 0, 0, getWidth(), getHeight(), this);
}
};
p.add(tabs);
p.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
return p;
}
public static void main(String... args) {
EventQueue.invokeLater(() -> {
JFrame f = new JFrame();
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.getContentPane().add(new TransparentTabbedPaneTest().makeUI());
f.setSize(320, 240);
f.setLocationRelativeTo(null);
f.setVisible(true);
});
}
}
//https://tips4java.wordpress.com/2009/05/31/backgrounds-with-transparency/
class AlphaContainer extends JComponent {
private JComponent component;
public AlphaContainer(JComponent component) {
this.component = component;
setLayout( new BorderLayout() );
setOpaque( false );
component.setOpaque( false );
add( component );
}
/**
* Paint the background using the background Color of the
* contained component
*/
#Override
public void paintComponent(Graphics g) {
g.setColor( component.getBackground() );
g.fillRect(0, 0, getWidth(), getHeight());
}
}

Painting issue in custom layered container?

So I am working on a project here that requires a custom JLayeredPane - like class.
It has two members 'ground' and 'foreground' that are JPanel and an background (Image) member.
The way it was supposed to show was that the background Image should have been drawn and then all the components of the ground on top of it and then foreground's components at the apex. So foreground covers up ground which covers up background. Background should be shown only at places that do not have a Component in ground and foreground or where there is transparency in the JPanels.
It's paint function goes like this:
#Override
public void paint(Graphics g){
g.drawImage(background, 0, 0, null);
ground.paint(g.create());
foreground.paint(g.create());
g.dispose();
}
But nothing like that happens. Just the background image gets painted and nothing else shows.
I have used System.out.println() function to check that ground and foreground actually hold components and they do. But they just don't show.
Can anyone help me here?

The most significant issue is you're not calling super.paint, which is preventing what ever was previously painted to the Graphics context from been cleared or any child components from been painted.
For painting the background, you should be using paintComponent, which is used to paint the background of the component.
If you need to paint under the child components, but above the background, you should still use paintComponent, but paint the background first and then the next layer. The components will be painted after paintComponent.
Painting over components is actually more complex
Take a closer look at Custom Painting and Painting in Swing and AWT
Updated based on code snippets
In Screen which extends from Container, you are doing...
#Override
public void paint(Graphics g) {
super.paint(g);
GraphicsUtilities.drawPictureTiled(background, g);
paintComponents(g);
g.dispose();
}
Don't call paintComponents, super.paint has already done this.
Don't call dispose on a Graphics context you don't create
Based on the rest of the example code I have, you should be extending from JPanel and overriding paintComponent instead. This will allow you to put under the component layer
Because GroundPanel and ForeGroundPanel are both JPanels, there's no need to ever paint them yourself. In fact, you could simply use OverlayLayout or even a GridBagLayout and add them directly to the NestedScreen which is itself a container...
So, I stripped down you example code so I could get it working with the missing code as an example. I got a little more fancy and simply made a JPanel to act as the pause screen
This is all done by simply overlaying the components on top of each other using a GridBagLayout
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test1001 {
public static void main(String[] args) {
new Test1001();
}
public Test1001() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
try {
NestedScreen screen = new NestedScreen();
screen.setBackgroundLayer(ImageIO.read(getClass().getResource("/Sky.png")));
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(screen);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
} catch (IOException exp) {
exp.printStackTrace();
}
}
});
}
public interface GraphicsEngineComponents {
}
public class NestedScreen extends Screen implements GraphicsEngineComponents {
GroundPanel ground;
ForeGroundPanel foreground;
private PausePane pausePane;
public NestedScreen() {
ground = new GroundPanel();
foreground = new ForeGroundPanel();
pausePane = new PausePane();
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(pausePane, gbc);
add(foreground, gbc);
add(ground, gbc);
MouseAdapter handler = new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
pausePane.setVisible(!pausePane.isVisible());
}
};
addMouseListener(handler);
foreground.addMouseListener(handler);
ground.addMouseListener(handler);
}
public GroundPanel getGroundLayer() {
return ground;
}
public ForeGroundPanel getForegroundLayer() {
return foreground;
}
public void setBackgroundLayer(BufferedImage background) {
super.setBackgroundLayer(background);
}
public class GroundPanel extends JPanel {
public GroundPanel() {
setOpaque(false);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.GREEN);
g.fillRect(0, getHeight() - 200, getWidth(), 200);
}
}
public class PausePane extends JPanel {
private JLabel label;
public PausePane() {
setVisible(false);
setOpaque(false);
setBackground(new Color(0, 0, 0, 128));
setLayout(new GridBagLayout());
label = new JLabel("Paused");
label.setHorizontalAlignment(JLabel.CENTER);
label.setVerticalAlignment(JLabel.CENTER);
Font font = label.getFont();
font = font.deriveFont(Font.BOLD, 48f);
label.setFont(font);
label.setForeground(Color.WHITE);
add(label);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), getHeight());
}
}
public class ForeGroundPanel extends JPanel {
private BufferedImage pony;
public ForeGroundPanel() {
setOpaque(false);
try {
pony = ImageIO.read(getClass().getResource("/Pony.png"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (pony != null) {
int x = (getWidth() - pony.getWidth()) / 2;
int y = getHeight() - 200 - (pony.getHeight() / 2);
g.drawImage(pony, x, y, this);
}
}
}
}
public class Screen extends JPanel implements GraphicsEngineComponents {
private BufferedImage background;
public Screen() {
}
#Override
public String toString() {
return "Screen{" + "background=" + background + '}';
}
public BufferedImage getBackgroundPicture() {
return background;
}
#Override
public Dimension getPreferredSize() {
return background == null ? super.getPreferredSize() : new Dimension(background.getWidth(), background.getHeight());
}
protected void setBackgroundLayer(BufferedImage background) {
if (background != null && background.getHeight() != 0 && background.getWidth() != 0) {
this.background = background;
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (background != null) {
g.drawImage(background, 0, 0, this);
}
}
}
}
Take a look at Painting in AWT and Swing and Performing Custom Painting to understand how painting works in Swing.
A basic idea would be to avoid using all these compound or nested components and instead, create an engine that can paint the layers directly onto a Graphics context, maybe even painting to a BufferedImage which you can the paint onto a single component...

There are a few ways you go about doing this. I'll just introduce one way.
Create a background panel where you paint the background image (in the example below, it is BackgroundPanel with the image only being the forresty background). Set that panel as the content pane to the frame.
Create another ground panel where you can also paint something (in the example below if it the GroundPanel with only the image of bugs bunny painted.
Create your foreground panel and add it to the ground panel. You can add your foreground components to it. (in the example below the foreground image is the grassy hill, and I also add a button to it
All the panels' opaque property should be set to false, as to allow the panel behind it to be shown under any transparency.
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.AbstractAction;
import javax.swing.InputMap;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
public class ThreeTier {
public static final int DIM_WIDTH = 600;
public static final int DIM_HEIGHT = 400;
private BufferedImage backgroundImage;
private BufferedImage groundImage;
private BufferedImage foregroundImage;
public ThreeTier() {
initImages();
JFrame frame = new JFrame();
frame.setContentPane(new BackgroundPanel());
frame.add(new GroundPanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private void initImages() {
try {
backgroundImage = ImageIO.read(getClass().getResource("/resources/background.png"));
foregroundImage = ImageIO.read(getClass().getResource("/resources/foreground.png"));
groundImage = ImageIO.read(getClass().getResource("/resources/bugsBunny.png"));
} catch (IOException ex) {
Logger.getLogger(ThreeTier.class.getName()).log(Level.SEVERE, null, ex);
}
}
class BackgroundPanel extends JPanel {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(backgroundImage, 0, 0, DIM_WIDTH, DIM_HEIGHT, this);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(ThreeTier.DIM_WIDTH, ThreeTier.DIM_HEIGHT);
}
}
class GroundPanel extends JPanel {
private static final String RIGHT_ACTION = "rightAction";
private int imageX = 50;
private int imageY = 140;
public GroundPanel() {
setOpaque(false);
add(new ForegroundPanel());
InputMap im = getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
im.put(KeyStroke.getKeyStroke("RIGHT"), RIGHT_ACTION);
getActionMap().put(RIGHT_ACTION, new AbstractAction() {
public void actionPerformed(ActionEvent e) {
if (imageX >= DIM_WIDTH) {
imageX = 0 - groundImage.getWidth();
repaint();
} else {
imageX += 10;
repaint();
}
}
});
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(groundImage, imageX, imageY, groundImage.getWidth(), groundImage.getHeight(), this);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(ThreeTier.DIM_WIDTH, ThreeTier.DIM_HEIGHT);
}
}
class ForegroundPanel extends JPanel {
public ForegroundPanel() {
setOpaque(false);
setLayout(new FlowLayout(FlowLayout.TRAILING, 10, 0));
JButton button = new JButton("I'm in the Foreground!");
add(button);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(foregroundImage, 0, 0, DIM_WIDTH, DIM_HEIGHT, this);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(ThreeTier.DIM_WIDTH, ThreeTier.DIM_HEIGHT);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ThreeTier();
}
});
}
}
UPDATE
Of course you could always just use the JLayeredPane. That's what it's for. See this example
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Image;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.LineBorder;
public class LayeredPaneDemo {
public static final int DIM_WIDTH = 600;
public static final int DIM_HEIGHT = 400;
public LayeredPaneDemo() {
ContainerPanel container = new ContainerPanel();
JLabel title = new JLabel("Lame Google Map");
title.setFont(new Font("verdana", Font.BOLD, 36));
title.setHorizontalAlignment(JLabel.CENTER);
JPanel panel = new JPanel(new GridBagLayout());
panel.add(container);
JFrame frame = new JFrame();
frame.add(panel);
frame.add(title, BorderLayout.NORTH);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new LayeredPaneDemo();
}
});
}
public class ContainerPanel extends JPanel {
public ContainerPanel() {
JLayeredPane layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(new Dimension(DIM_WIDTH, DIM_HEIGHT));
BackgroundPanel bg = new BackgroundPanel();
GroundPanel gg = new GroundPanel();
ForegroundPanel fg = new ForegroundPanel();
bg.setBounds(0, 0, DIM_WIDTH, DIM_HEIGHT);
layeredPane.add(bg, new Integer(1));
gg.setBounds(0, 0, DIM_WIDTH, DIM_HEIGHT);
layeredPane.add(gg, new Integer(2));
fg.setBounds(0, 0, DIM_WIDTH, DIM_HEIGHT);
layeredPane.add(fg, new Integer(3));
setLayout(new GridBagLayout());
add(layeredPane);
setBorder(new LineBorder(Color.BLUE, 10));
}
}
public class ForegroundPanel extends JPanel {
public ForegroundPanel() {
JPanel buttonPanel = new JPanel(new GridLayout(3, 3));
buttonPanel.setOpaque(false);
buttonPanel.add(new JLabel());
buttonPanel.add(new JButton("UP"));
buttonPanel.add(new JLabel());
buttonPanel.add(new JButton("Left"));
buttonPanel.add(new JLabel());
buttonPanel.add(new JButton("Right"));
buttonPanel.add(new JLabel());
buttonPanel.add(new JButton("Down"));
buttonPanel.add(new JLabel());
FlowLayout flow = (FlowLayout) getLayout();
flow.setAlignment(FlowLayout.TRAILING);
flow.setHgap(0);
flow.setVgap(0);
add(buttonPanel);
setOpaque(false);
}
}
public class GroundPanel extends JPanel {
Image image = null;
public GroundPanel() {
try {
image = ImageIO.read(getClass().getResource("/resources/california.png"));
} catch (IOException ex) {
Logger.getLogger(LayeredPaneDemo.class.getName()).log(Level.SEVERE, null, ex);
}
setOpaque(false);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, DIM_WIDTH, DIM_HEIGHT, this);
}
}
public class BackgroundPanel extends JPanel {
public BackgroundPanel() {
setLayout(new GridBagLayout());
setBackground(Color.WHITE);
try {
Image img = ImageIO.read(getClass().getResource("/resources/google.jpg"));
add(new JLabel(new ImageIcon(img)));
} catch (IOException ex) {
Logger.getLogger(LayeredPaneDemo.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}

Drawing directly on glasspane: not working

I am developing an app using Swing. While user interact with the app, help data may become available in a closed section of the screen, and I'd like to draw a small arrow pointing to that section when this happens.
To do this, I extended a JPanel and added it as the glasspane of the app jframe. The name of the custom glass pane class is AlertGlassPane.
The AlertGlassPane do this: waits until new help data is available. When this happens and the help section is closed, it finds the position of the help section on the screen and then draws an animated arrow at its side.
To draw the arrow I extended the method paintComponent of the glass pane.
To animate the arrow I created a small thread that loop every 100 ms, calling repaint on the glass pane.
The problem: Java ignores my drawing... if a trigger the start of the animation and stand still, nothing happens. No drawing is shown on the app.
I know that the loop is running and paintComponent is being called, but the custom paint is not taking effect.
But if I move the mouse over the region where the arrow should be rendered, it does! But just when the mouse is moving. If a stop move the mouse, the animation stops too, and the arrow freezes on the last position before the mouse stop (or leaves the area).
I tried a lot of things (as set the clip region of the drawing, for example), but nothing seems to work. The only thing that works was when I called by mistake repaint from inside the paintComponent.
At this moment I'm looking for a way to comunicate to the rendering system that a givem region of my glasspane needs to be repainted (repaint(x, y, w, h) didn't work...). Maybe moving the custom rendering to a JLabel and then adding this label to the glasspane? I don't like this approach...
I'll try to clean up the code before post a snippet here. Would it help?
Thanks in advance!
snnipet:
package br.com.r4j.test;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.image.BufferedImage;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.text.JTextComponent;
/**
*
* #author
*/
public class TestGlassPaneAnimation extends JPanel
{
private static TestGlassPaneAnimation gvp = new TestGlassPaneAnimation();
public static void main(String args[])
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
JFrame f = new JFrame("Anitest in glass");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//f.setResizable(false);
f.setLayout(new GridLayout(5, 3));
f.add(new JLabel("First Name :"));
f.add(new JTextField(20));
f.add(new JLabel("Last Name :"));
f.add(new JTextField(20));
f.add(new JLabel("Phone Number :"));
f.add(new JTextField(20));
f.add(new JLabel("Email:"));
f.add(new JTextField(20));
f.add(new JLabel("Address :"));
f.add(new JTextField(20));
JButton btnStart = new JButton("Click me, please!");
f.add(btnStart);
btnStart.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
gvp.startAnimation();
}
});
f.setGlassPane(gvp);
f.pack();
f.setVisible(true);
gvp.setVisible(true);
}
});
}
private BufferedImage icon;
private boolean animate = false;
private long timeStart = 0;
private Thread thrLastActive = null;
public TestGlassPaneAnimation()
{
setLayout(null);//this is the exception to the rule case a layoutmanager might make setting Jlabel co-ords harder
setOpaque(false);
Icon icon1 = UIManager.getIcon("OptionPane.warningIcon");
int imgW = icon1.getIconWidth();
int imgH = icon1.getIconHeight();
this.icon = ImageUtilities.getBufferedImageOfIcon(icon1, imgW, imgH);
this.animate = false;
}
public void startAnimation()
{
this.animate = true;
this.timeStart = (new Date()).getTime();
if (this.thrLastActive != null)
this.thrLastActive.interrupt();
this.thrLastActive = new Thread(new Runnable()
{
public void run()
{
try
{
while (true)
{
// int x = 250, y = 250;
// int width = 60, height = 60;
Thread.currentThread().sleep(100);
// frmRoot.invalidate();
// repaint(x, y, width, height);
repaint(new Rectangle(x, y, width, height));
// repaint(new Rectangle(10, 10, 2000, 2000));
// repaint();
// paintComponent(getGraphics());
}
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
this.thrLastActive.start();
}
protected void paintComponent(Graphics g)
{
try
{
// enables anti-aliasing
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
java.awt.Composite composite = g2.getComposite();
System.err.println("b1: " + g.getClipBounds());
if (this.animate)
{
long timeSpent = (new Date()).getTime() - timeStart;
int x = 10, y = 150;
int width = 60, height = 60;
float maxAlpha = 0.8f;
x += (-100*Math.sin(5*2*Math.PI*timeSpent/10000)+50)/15;
System.err.println("painting::x: " + x + ", y: " + y + ", sin: " + (Math.sin(6*2*Math.PI*timeSpent/10000)));
// g.setClip(x-10, y-10, width, height);
System.err.println("b2: " + g.getClipBounds());
AlphaComposite alpha2 = AlphaComposite.SrcOver.derive(maxAlpha);
g2.setComposite(alpha2);
g2.drawImage(this.icon, x, y, null);
g2.setComposite(composite);
g2.setComposite(composite);
}
}
catch (Throwable e)
{
System.err.println("Errr!");
e.printStackTrace();
}
}
}
class ImageUtilities {
public static BufferedImage resize(BufferedImage image, int width, int height) {
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TRANSLUCENT);
Graphics2D g2d = (Graphics2D) bi.createGraphics();
g2d.addRenderingHints(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY));
g2d.drawImage(image, 0, 0, width, height, null);
g2d.dispose();
return bi;
}
public static BufferedImage getBufferedImageOfIcon(Icon icon, int imgW, int imgH) {
BufferedImage img = new BufferedImage(imgW, imgH, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = (Graphics2D) img.getGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
icon.paintIcon(null, g2d, 0, 0);
g2d.dispose();
return img;
}
}

Hmm not sure exactly whats going on with the snippet you gave but as it looks like it was taken from mine I wrote another example (I had to change a 1 or 2 lines of code in showWarningIcon(Component c) and refreshLocations() methods but nothing major:
If anything except david is typed and the button (click me, please) clicked it will show this:
import java.awt.Component;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.image.BufferedImage;
import java.util.HashMap;
import java.util.Map;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
public class TestGlassPaneAnimation {
private static GlassValidationPane gvp = new GlassValidationPane();
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame("Anitest in glass");
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
//f.setResizable(false);
f.setLayout(new GridBagLayout());
GridBagConstraints gc = new GridBagConstraints();
gc.fill = GridBagConstraints.HORIZONTAL;
gc.weightx = 1;
gc.weighty = 1;
gc.insets = new Insets(15, 15, 15, 15);//give some space so icon doesnt cover components when shown
gc.gridx = 0;
gc.gridy = 0;
f.add(new JLabel("First Name:"), gc);
final JTextField jtf = new JTextField(20);
gc.gridx = 1;
f.add(jtf, gc);
gc.gridx = 0;
gc.gridy = 1;
f.add(new JLabel("Surname:"), gc);
final JTextField jtf2 = new JTextField(20);
gc.gridx = 1;
f.add(jtf2, gc);
JButton btnStart = new JButton("Click me, please!");
gc.gridx = 2;
f.add(btnStart, gc);
btnStart.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (!jtf.getText().equalsIgnoreCase("david")) {
gvp.showWarningIcon(jtf);
}
}
});
f.addComponentListener(new ComponentAdapter() {//so wjen frame is resized icons follow
#Override
public void componentResized(ComponentEvent ce) {
super.componentResized(ce);
gvp.refreshLocations();
}
});
f.setGlassPane(gvp);
f.pack();
f.setVisible(true);
gvp.setVisible(true);
}
});
}
}
class GlassValidationPane extends JPanel {
private HashMap<Component, JLabel> warningLabels = new HashMap<>();
private ImageIcon warningIcon;
public GlassValidationPane() {
setLayout(null);//this is the exception to the rule case a layoutmanager might make setting Jlabel co-ords harder
setOpaque(false);
Icon icon = UIManager.getIcon("OptionPane.warningIcon");
int imgW = icon.getIconWidth();
int imgH = icon.getIconHeight();
BufferedImage img = ImageUtilities.getBufferedImageOfIcon(icon, imgW, imgH);
warningIcon = new ImageIcon(ImageUtilities.resize(img, 24, 24));
}
void showWarningIcon(Component c) {
if (warningLabels.containsKey(c)) {
return;
}
JLabel label = new JLabel();
label.setIcon(warningIcon);
//int x=c.getX();//this will make it insode the component
int x = c.getX() - warningIcon.getIconWidth();//this makes it appear outside/next to component if space
int y = c.getY();
label.setBounds(x, y, warningIcon.getIconWidth(), warningIcon.getIconHeight());
add(label);
revalidate();
repaint();
warningLabels.put(c, label);
}
public void removeWarningIcon(Component c) {
for (Map.Entry<Component, JLabel> entry : warningLabels.entrySet()) {
Component component = entry.getKey();
JLabel jLabel = entry.getValue();
if (component == c) {
remove(jLabel);
revalidate();
repaint();
break;
}
}
warningLabels.remove(c);
}
public void refreshLocations() {
for (Map.Entry<Component, JLabel> entry : warningLabels.entrySet()) {
Component c = entry.getKey();
JLabel label = entry.getValue();
//int x=c.getX();//this will make it insode the component
int x = c.getX() - label.getIcon().getIconWidth();//this makes it appear outside/next to component
int y = c.getY();
label.setBounds(x, y, label.getIcon().getIconWidth(), label.getIcon().getIconHeight());
revalidate();
repaint();
}
}
}
class ImageUtilities {
public static BufferedImage resize(BufferedImage image, int width, int height) {
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TRANSLUCENT);
Graphics2D g2d = (Graphics2D) bi.createGraphics();
g2d.addRenderingHints(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY));
g2d.drawImage(image, 0, 0, width, height, null);
g2d.dispose();
return bi;
}
public static BufferedImage getBufferedImageOfIcon(Icon icon, int imgW, int imgH) {
BufferedImage img = new BufferedImage(imgW, imgH, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = (Graphics2D) img.getGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
icon.paintIcon(null, g2d, 0, 0);
g2d.dispose();
return img;
}
}
If you are looking for a more mature library have a look at JXLayer - Validation Overlays and Validation overlays using glass pane.
Also might want to have a read here which shows many ways of validating a textfields data (other than button press) like DocumentFilter and InputVerifier etc.

Drawing warning symbol during form validation in Swing

I have developed a swing form which validates entries as the focus is lost from JTextComponent
and if the entry is correct ,the background is painted green Otherwise it is painted red.
Here is the code :-
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.text.JTextComponent;
public class Form extends JFrame implements FocusListener{
JTextField fname,lname,phone,email,address;
BufferedImage img;
public static void main(String args[])
{
SwingUtilities.invokeLater(new Runnable(){public void run(){new Form();}});
}
public Form()
{
super("Form with Validation Capability");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400,300);
setLayout(new GridLayout(5,3));
try {
img=ImageIO.read(new File("src/warning.png"));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
add(new JLabel("First Name :"));
add(fname=new JTextField(20));
add(new JLabel("Last Name :"));
add(lname=new JTextField(20));
add(new JLabel("Phone Number :"));
add(phone=new JTextField(10));
add(new JLabel("Email:"));
add(email=new JTextField(20));
add(new JLabel("Address :"));
add(address=new JTextField(20));
fname.addFocusListener(this);
lname.addFocusListener(this);
phone.addFocusListener(this);
email.addFocusListener(this);
address.addFocusListener(this);
setVisible(true);
}
public void focusGained(FocusEvent e)
{
((JTextComponent) e.getSource()).setBackground(Color.WHITE);
}
public void focusLost(FocusEvent e)
{
if(e.getSource().equals(fname))
{
validationForText(fname);
}
else if(e.getSource().equals(lname))
{
validationForText(lname);
}
else if(e.getSource().equals(email))
{
validationForEmail(email);
}
else if(e.getSource().equals(phone))
{
validationForNumber(phone);
}
else{
((JTextComponent) e.getSource()).setBackground(Color.GREEN);
}
}
public void validationForText(JTextComponent comp)
{
String temp=comp.getText();
if (temp.matches("^[A-Za-z]+$")) {
comp.setBackground(Color.GREEN);
}
else
comp.setBackground(Color.RED);
}
public void validationForNumber(JTextComponent comp)
{
String text=comp.getText();
if(text.matches("^[0-9]+$"))
comp.setBackground(Color.GREEN);
else
comp.setBackground(Color.RED);
}
public void validationForEmail(JTextComponent comp)
{
String text=comp.getText();
if(text.matches("[^#]+#([^.]+\\.)+[^.]+"))
comp.setBackground(Color.GREEN);
else
comp.setBackground(Color.RED);
}
}
Here is the output to my simple app :
Now I also want to draw a warning symbol (buffered image) at the lower left corner of incorrect field.Can anyone help me how to do this as i am not understanding where to paint the image.
(I would like to do it using JLayeredPane as I am learning its application,any code snippet will really help).

Why not simply add a JLabel (using an appropriate LayoutManager to position it) with the inbuilt Swing warning icon UIManager.getIcon("OptionPane.warningIcon")
like so:
JLabel label=new JLabel(UIManager.getIcon("OptionPane.warningIcon"));
see here for more.
UPDATE:
As per your comment I would rather use GlassPane (and add JLabel to glasspane) for this as opposed too JLayeredPane. See here for more on RootPanes
Some suggestions:
Dont extend JFrame unnecessarily
Dont call setSize on JFrame. Use a correct LayoutManager and/or override getPreferredSize() where necessary and replace setSize call with pack() just before setting JFrame visible.
Dont implement FocusListener on the class unless you want to share the functionality with other classes.
Also get into the habit of using FocusAdapter vs FocusListener this applies to a few with appended Listener i.e MouseListener can be replaced for MouseAdapter. This allows us to only override the methods we want. In this case listener is correct as we do something on both overridden methods, but as I said more about the habit
Also always call super.XXX implementation of overridden methods i.e focusGained(FocusEvent fe) unless you are ignoring it for a reason
Here is code with above fixes including glasspane to show warning icon when field is red:
And removes it when is corrected:
import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.RenderingHints;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.image.BufferedImage;
import java.util.HashMap;
import java.util.Map;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.text.JTextComponent;
/**
*
* #author David
*/
public class GlassValidationPane extends JComponent {
private static JTextField fname, lname, phone, email, address;
private static GlassValidationPane gvp = new GlassValidationPane();
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame("Form with Validation Capability");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//f.setResizable(false);
f.setLayout(new GridLayout(5, 3));
f.add(new JLabel("First Name :"));
f.add(fname = new JTextField(20));
f.add(new JLabel("Last Name :"));
f.add(lname = new JTextField(20));
f.add(new JLabel("Phone Number :"));
f.add(phone = new JTextField(10));
f.add(new JLabel("Email:"));
f.add(email = new JTextField(20));
f.add(new JLabel("Address :"));
f.add(address = new JTextField(20));
f.addComponentListener(new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent ce) {
super.componentResized(ce);
gvp.refreshLocations();
}
});
FocusAdapter fl = new FocusAdapter() {
#Override
public void focusGained(FocusEvent fe) {
super.focusGained(fe);
((JTextComponent) fe.getSource()).setBackground(Color.WHITE);
}
#Override
public void focusLost(FocusEvent fe) {
super.focusLost(fe);
if (fe.getSource().equals(fname)) {
validationForText(fname);
} else if (fe.getSource().equals(lname)) {
validationForText(lname);
} else if (fe.getSource().equals(email)) {
validationForEmail(email);
} else if (fe.getSource().equals(phone)) {
validationForNumber(phone);
} else {
gvp.removeWarningIcon(((Component) fe.getSource()));
((JTextComponent) fe.getSource()).setBackground(Color.GREEN);
}
}
};
fname.addFocusListener(fl);
lname.addFocusListener(fl);
phone.addFocusListener(fl);
email.addFocusListener(fl);
address.addFocusListener(fl);
f.setGlassPane(gvp);
f.pack();
f.setVisible(true);
gvp.setVisible(true);
}
public void validationForText(JTextComponent comp) {
String temp = comp.getText();
if (temp.matches("^[A-Za-z]+$")) {
setGreen(comp);
} else {
setRed(comp);
}
}
public void validationForNumber(JTextComponent comp) {
String text = comp.getText();
if (text.matches("^[0-9]+$")) {
setGreen(comp);
} else {
setRed(comp);
}
}
public void validationForEmail(JTextComponent comp) {
String text = comp.getText();
if (text.matches("[^#]+#([^.]+\\.)+[^.]+")) {
setGreen(comp);
} else {
setRed(comp);
}
}
private void setRed(JTextComponent comp) {
comp.setBackground(Color.RED);
gvp.showWarningIcon(comp);
}
private void setGreen(JTextComponent comp) {
comp.setBackground(Color.GREEN);
gvp.removeWarningIcon(comp);
}
});
}
private HashMap<Component, JLabel> warningLabels = new HashMap<>();
private ImageIcon warningIcon;
public GlassValidationPane() {
setLayout(null);//this is the exception to the rule case a layoutmanager might make setting Jlabel co-ords harder
setOpaque(false);
Icon icon = UIManager.getIcon("OptionPane.warningIcon");
int imgW = icon.getIconWidth();
int imgH = icon.getIconHeight();
BufferedImage img = ImageUtilities.getBufferedImageOfIcon(icon, imgW, imgH);
warningIcon = new ImageIcon(ImageUtilities.resize(img, 24, 24));
}
void showWarningIcon(Component c) {
if (warningLabels.containsKey(c)) {
return;
}
JLabel label = new JLabel();
label.setIcon(warningIcon);
//int x=c.getX();//this will make it insode the component
int x = c.getWidth() - label.getIcon().getIconWidth();//this makes it appear outside/next to component
int y = c.getY();
label.setBounds(x, y, label.getIcon().getIconWidth(), label.getIcon().getIconHeight());
add(label);
label.setVisible(true);
revalidate();
repaint();
warningLabels.put(c, label);
}
public void removeWarningIcon(Component c) {
for (Map.Entry<Component, JLabel> entry : warningLabels.entrySet()) {
Component component = entry.getKey();
JLabel jLabel = entry.getValue();
if (component == c) {
remove(jLabel);
revalidate();
repaint();
break;
}
}
warningLabels.remove(c);
}
public void refreshLocations() {
for (Map.Entry<Component, JLabel> entry : warningLabels.entrySet()) {
Component c = entry.getKey();
JLabel label = entry.getValue();
//int x=c.getX();//this will make it insode the component
int x = c.getWidth() - label.getIcon().getIconWidth();//this makes it appear outside/next to component
int y = c.getY();
label.setBounds(x, y, label.getIcon().getIconWidth(), label.getIcon().getIconHeight());
revalidate();
repaint();
}
}
}
class ImageUtilities {
public static BufferedImage resize(BufferedImage image, int width, int height) {
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TRANSLUCENT);
Graphics2D g2d = (Graphics2D) bi.createGraphics();
g2d.addRenderingHints(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY));
g2d.drawImage(image, 0, 0, width, height, null);
g2d.dispose();
return bi;
}
public static BufferedImage getBufferedImageOfIcon(Icon icon, int imgW, int imgH) {
BufferedImage img = new BufferedImage(imgW, imgH, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = (Graphics2D) img.getGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
icon.paintIcon(null, g2d, 0, 0);
g2d.dispose();
return img;
}
}