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Set Transparent Color for the Whole JPanel

I have a JPanel with a JLabel which owns an Icon picture.
how do I set a transparent red color at the top of the whole JPanel (including JLabel Icon)?
I have the transparent backgriound color on for the panel but I want the whole panel including the picture and everything get this transparent color. something like a transparent colorful glass at the top of the JPanel
import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class TransparentJLabel {
private static final String IMAGE_PATH = "http://duke.kenai.com/Oracle/OracleStratSmall.png";
private static void createAndShowUI() {
JPanel panel = new JPanel();
panel.setBackground(Color.pink);
URL imageUrl;
try {
imageUrl = new URL(IMAGE_PATH);
BufferedImage image = ImageIO.read(imageUrl);
ImageIcon icon = new ImageIcon(image);
JLabel label = new JLabel(icon);
panel.add(label);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
JFrame frame = new JFrame("TransparentJLabel");
frame.getContentPane().add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}

If you just need a layered panel over the whole contentPane, a simple glassPane will do fine (override it's paintComponent(...) method). For example:
JPanel glassPane = new JPanel() {
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g.create();
g2.setColor(new Color(0, 100, 0, 100));
g2.fillRect(0, 0, getWidth(), getHeight());
g2.dispose();
}
};
glassPane.setOpaque(false);
frame.setGlassPane(glassPane);
frame.getGlassPane().setVisible(true);
However, if you want a layered panel over only one JPanel, I would use JLayer combined with LayerUI, as MadProgrammer already mentioned. You will need a custom LayerUI in which you override the paint(Graphics g, JComponent c) method. I know that sounds dangerous, but I honestly don't know of another way of doing it...
I've provided an example below, this is the output:
As you can see, panel1 (or more accurately, the JLayer) is slighty transparent (RGBA = "0, 100, 0, 100") and panel2 is normal.
Code:
import java.awt.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.*;
import javax.swing.plaf.LayerUI;
public class Example {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new Example();
}
});
}
public Example() {
JFrame frame = new JFrame("Example");
JPanel panel1 = new JPanel();
panel1.add(new JButton("Panel 1"));
MyLayerUI layerUI = new MyLayerUI();
JLayer<JPanel> panel1Layer = new JLayer<JPanel>(panel1, layerUI);
panel1.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
if (layerUI.hasOverlay()) {
layerUI.setOverlay(false);
} else {
layerUI.setOverlay(true);
}
panel1Layer.repaint();
}
});
JPanel panel2 = new JPanel();
panel2.add(new JButton("Panel 2"));
JPanel contentPane = new JPanel(new GridLayout(2, 1));
contentPane.add(panel1Layer);
contentPane.add(panel2);
frame.setContentPane(contentPane);
frame.setSize(300, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
class MyLayerUI extends LayerUI<JPanel> {
private boolean overlay = true;
#Override
public void paint(Graphics g, JComponent c) {
super.paint(g, c);
if (hasOverlay()) {
Graphics2D g2 = (Graphics2D) g.create();
g2.setColor(new Color(0, 100, 0, 100));
g2.fillRect(0, 0, c.getWidth(), c.getHeight());
g2.dispose();
}
}
public boolean hasOverlay() {
return overlay;
}
public void setOverlay(boolean overlay) {
this.overlay = overlay;
}
}

Java - Creating PNG/Textlogo and drawing it to JFrame

I'm trying to print a string that the user can enter to a textbox, to a JFrame.
My problem is that the paintComponent method is never being called. Why?
PNGCreatorWindow Class:
public class PNGCreatorWindow {
private JFrame frame;
private JTextField txtText;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
PNGCreatorWindow window = new PNGCreatorWindow();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public PNGCreatorWindow() {
initialize();
}
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 678, 502);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
txtText = new JTextField();
txtText.setBounds(121, 13, 216, 22);
frame.getContentPane().add(txtText);
txtText.setColumns(10);
JButton btnGenerate = new JButton("Generate");
btnGenerate.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
}
});
btnGenerate.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent arg0) {
GeneratePNGImage();
}
});
btnGenerate.setBounds(436, 6, 183, 36);
frame.getContentPane().add(btnGenerate);
JPanel panel = new JPanel();
panel.setBounds(107, 151, 338, 160);
frame.getContentPane().add(panel);
}
protected void GeneratePNGImage() {
PNGImage img = new PNGImage(txtText.getText());
frame.getContentPane().add(img);
frame.getContentPane().validate();
frame.getContentPane().setVisible(true);
frame.repaint();
}
}
PNGImage Class:
public class PNGImage extends JComponent {
private String text;
public PNGImage(String text){
this.text = text;
}
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
g2.setColor(Color.red);
g2.drawString(this.text, 100,100);
g2.fillRect(50, 50, 1000, 1000);
}
}

I made a few changes to your code to get it to draw the text on the JPanel.
I put the JTextField and the JButton inside of a control panel (JPanel) and set a layout manager (FlowLayout) for the control panel. You should always use a layout manager for laying out Swing components.
I defined the image panel (PNGImage) as part of the laying out of the Swing components. First, you lay all of the Swing components out. Then, you change their state.
I removed the mouse adapter and just used an action listener on the JButton. The action listener works with the mouse.
In the PNGImage class, I added a setter, so I could pass the text to the class later, after the user typed the text in the JTextField.
I added a call to setPreferredSize so that I could set the size of the drawing canvas. I removed all other sizing, and used the pack method of JFrame to make the JFrame the appropriate size to hold the Swing components.
I added a null test to paintComponent, so that the text would only be drawn when there was some text to draw.
Here's the code. I put all the code in one module to make it easier to paste.
package com.ggl.testing;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class PNGCreatorWindow {
private JFrame frame;
private JTextField txtText;
private PNGImage imagePanel;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
new PNGCreatorWindow();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public PNGCreatorWindow() {
initialize();
}
private void initialize() {
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel controlPanel = new JPanel();
controlPanel.setLayout(new FlowLayout());
txtText = new JTextField(10);
controlPanel.add(txtText);
JButton btnGenerate = new JButton("Generate");
btnGenerate.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
generatePNGImage();
}
});
controlPanel.add(btnGenerate);
imagePanel = new PNGImage();
frame.getContentPane().add(controlPanel, BorderLayout.NORTH);
frame.getContentPane().add(imagePanel, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
protected void generatePNGImage() {
imagePanel.setText(txtText.getText());
imagePanel.repaint();
}
public class PNGImage extends JPanel {
private static final long serialVersionUID = 602718701626241645L;
private String text;
public PNGImage() {
setPreferredSize(new Dimension(400, 300));
}
public void setText(String text) {
this.text = text;
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
if (this.text != null) {
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.red);
g2.drawString(this.text, 100, 100);
}
}
}
}
Edited to add an action listener that saves the contents of a JPanel as a .png file:
package com.ggl.crossword.controller;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.awt.image.RenderedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFileChooser;
import javax.swing.JPanel;
import javax.swing.filechooser.FileFilter;
import javax.swing.filechooser.FileNameExtensionFilter;
import com.ggl.crossword.view.CrosswordFrame;
public class CreateImageActionListener implements ActionListener {
private CrosswordFrame frame;
private JPanel panel;
public CreateImageActionListener(CrosswordFrame frame,
JPanel panel) {
this.frame = frame;
this.panel = panel;
}
#Override
public void actionPerformed(ActionEvent event) {
writeImage();
}
public void writeImage() {
FileFilter filter =
new FileNameExtensionFilter("PNG file", "png");
JFileChooser fc = new JFileChooser();
fc.setFileFilter(filter);
int returnValue = fc.showSaveDialog(frame.getFrame());
if (returnValue == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
if (!file.getAbsolutePath().endsWith(".png")) {
file = new File(file.getAbsolutePath() + ".png");
}
RenderedImage image = createImage(panel);
try {
ImageIO.write(image, "png", file);
} catch (IOException e) {
e.printStackTrace();
}
}
}
private BufferedImage createImage(JPanel panel) {
int w = panel.getWidth();
int h = panel.getHeight();
BufferedImage bi = new BufferedImage(w, h,
BufferedImage.TYPE_INT_RGB);
Graphics2D g = bi.createGraphics();
panel.paint(g);
g.dispose();
return bi;
}
}

Im not sure how to get the data from my text field

I want to get the data from my textfield and set it to int h. and have that change the size of the rectangle im drawing, but im not sure how to go get the data from the textfield, I tired using e.getsource in actionperfomred but it cannot find my textfield. My code is below:
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;
import javax.swing.*;
import java.net.*;
import java.sql.*;
import java.lang.Object;
import java.awt.Graphics;
import java.awt.Graphics2D;
/**
* This class demonstrates how to load an Image from an external file
*/
public class test extends Component {
int x=77, y=441, w=23, h=10;
BufferedImage img =
new BufferedImage(100, 50,
BufferedImage.TYPE_INT_ARGB);
// BufferedImage img;
public void paint(Graphics g) {
g.drawImage(img, 0, 0, null);
// g.fillRect(10,10,10,10);
}
public test() {
try {
img = ImageIO.read(new File("sales-goal.png"));
} catch (IOException e) {}
Graphics2D g = img.createGraphics();
Color myColor = Color.decode("#32004b");
g.setColor(myColor);
g.fillRect(x,y,w,h);
//77,441,23,10
}
public Dimension getPreferredSize() {
if (img == null) {
return new Dimension(100,100);
} else {
//return new Dimension(img.getWidth(null), img.getHeight(null));
return new Dimension(300,600);
}
}
public static void main(String[] args) {
JFrame f = new JFrame("Load Image Sample");
JTextField textField=new JTextField();
f.add(textField);
textField.setBounds(10,10,40,30);
textField.setVisible(true);
f.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
f.add(new test());
f.pack();
f.setVisible(true);
}
public void actionPerformed(ActionEvent e) {
// if (e.getSource() == textField) {}
}
}

The variable textField is local to main. If you want to access it from actionPerformed, you'll need to change it to an instance variable.

Yeah. I agree with #jpm. You need to declare it as an instance variable.
Do the following:-
public class test extends Component {
//Declare the variable here.
private static JTextField textfield;
public static void main(String[] args) {
//Whenever you use the textfield use like this. Remove the keyword 'JTextField'.
textfield = new JTextField();
}
}

Im not sure how to get the data from my text field

My text field is local to main so I cannot access it from actionPerformed, I believe I need to make it a instance variable but I'm not sure how to because my frame is also in main so I'm not sure how I would then add it to the frame.
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;
import javax.swing.*;
import java.net.*;
import java.sql.*;
import java.lang.Object;
import java.awt.Graphics;
import java.awt.Graphics2D;
/**
* This class demonstrates how to load an Image from an external file
*/
public class Test extends JPanel {
int x=77, y=441, w=23, h=10;
BufferedImage img =
new BufferedImage(100, 50,
BufferedImage.TYPE_INT_ARGB);
// BufferedImage img;
public void paintComponent(Graphics g) {
g.drawImage(img, 0, 0, null);
// g.fillRect(10,10,10,10);
}
public Test() {
try {
img = ImageIO.read(new File("sales-goal.png"));
} catch (IOException e) {}
Graphics2D g = img.createGraphics();
Color myColor = Color.decode("#32004b");
g.setColor(myColor);
g.fillRect(x,y,w,h);
//77,441,23,10
}
public Dimension getPreferredSize() {
if (img == null) {
return new Dimension(100,100);
} else {
//return new Dimension(img.getWidth(null), img.getHeight(null));
return new Dimension(300,600);
}
}
public static void main(String[] args) {
JFrame f = new JFrame("Load Image Sample");
JTextField textField=new JTextField();
f.add(textField);
textField.setBounds(10,10,40,30);
textField.setVisible(true);
f.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
f.add(new Test());
f.pack();
f.setVisible(true);
}
public void actionPerformed(ActionEvent e) {
//if (e.getSource() == textField) {}
}
}

I think that you should not set up your swing application this way. Instead of creating everything in the main method you should create a subclass of JFrame and do the initialization in its constructor (or something like that). This class can then hold references to the components it contains. Example:
public class TestFrame extends JFrame {
private JTextField textField;
public TestFrame() {
super("Load Image Sample");
textField = new JTextField();
this.add(textField);
textField.setBounds(10,10,40,30);
textField.setVisible(true);
this.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
this.add(new Test());
this.pack();
this.setVisible(true);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == textField) {
// ...
}
}
}

create your frame and initialize it inside constructor.
public static void main(String[] args) {
new Test();
}

The event handling method actionPerformed must be registered by an ActionListener interface. As both textField and Test are components of the JFrame a logical place would be the JFrame, or a separate controller class that wires everything together.
I have rewritten your code with a more conventional approach on some details. For that I introduced a new class MyFrame.
public class MyFrame extends JFrame implements ActionListener {
JTextField textField = new JTextField();
public MyFrame(String title) {
super(title); // Or constructor without parameters and:
setTitle("Load Image Sample");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//setLayout(...); for instance with null for absolute positioning
add(textField);
textField.setBounds(10, 10, 40, 30);
textField.setVisible(true);
Test panel = new Test();
add(panel);
pack();
}
public static void main(String[] args) {
JFrame f = new MyFrame("Load Image Sample");
f.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("Text: " + textField.getText());
}
}
And then your JPanel
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JPanel;
/**
* This class demonstrates how to load an Image from an external file
*/
class Test extends JPanel {
int x = 77, y = 441, w = 23, h = 10;
BufferedImage img;
Color myColor = Color.decode("#32004b");
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(myColor);
g.fillRect(x, y, w, h);
g.drawImage(img, 0, 0, null);
// g.fillRect(10,10,10,10);
}
public Test() {
setBackground(Color.red);
try {
img = ImageIO.read(new File("sales-goal.png"));
} catch (IOException e) {
img = new BufferedImage(100, 50, BufferedImage.TYPE_INT_ARGB);
}
setPreferredSize(new Dimension(300, 600));
}
}

Page is not refreshing or not getting the input from my text field [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Im not sure how to get the data from my text field
I am entering a number into a text field and using that input to change an int which will change the size of a rectangle, Im not sure if something is wrong, where im not getting that data from that textfield or the page is just not reloading after it gets that data.
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;
import javax.swing.*;
import java.net.*;
import java.sql.*;
import java.lang.Object;
import java.awt.Graphics;
import java.awt.Graphics2D;
public class Test extends JPanel implements ActionListener{
JTextField textField;
JFrame f=new JFrame();
int x=77, y=441, w=23, h=10, entry;
BufferedImage img=null;
// BufferedImage img;
public static void main(String[] args) {
BufferedImage img =new BufferedImage(100, 50,BufferedImage.TYPE_INT_ARGB);
//textField = new JTextField();
JFrame f = new JFrame("Load Image Sample");
JTextField textField=new JTextField();
f.add(textField);
textField.setBounds(10,10,40,30);
textField.setVisible(true);
f.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
f.add(new Test());
f.pack();
f.setVisible(true);
}
public void paintComponent(Graphics g) {
g.drawImage(img, 0, 0, null);
Graphics2D i = img.createGraphics();
Color myColor = Color.decode("#32004b");
i.setColor(myColor);
i.fillRect(x,y,w,h);
// g.fillRect(10,10,10,10);
}
public Test() {
try {
img = ImageIO.read(new File("sales-goal.png"));
} catch (IOException e) {}
//77,441,23,10
}
public Dimension getPreferredSize() {
if (img == null) {
return new Dimension(100,100);
} else {
//return new Dimension(img.getWidth(null), img.getHeight(null));
return new Dimension(300,600);
}
}
public void actionPerformed(ActionEvent e) {
Graphics g= getGraphics();
textField.addActionListener(this);
if (e.getSource() == textField) {
entry= Integer.parseInt(textField.getText());
g.drawString("Test",50,50);
entry=h;
}
}
}

You are doing
JTextField textField=new JTextField();
in the main method which is creating a new local variable but your global JTextField textField; is never assigned. In your actionPerformed, you are using the global textField which is never initialized.

Declare the variable as
private static JTextField textField;
Remove 'JTextField' and use it as
textField = new JTextField();
in your main method

I would replace this line in your main method:
JTextField textField=new JTextField();
With these:
textField=new JTextField();
textField.addActionListener(this);
Then I would remove this line from your actionPerformed method:
textField.addActionListener(this);