I'm on Ubuntu 15.04 and I have written following program:
import java.awt.Frame;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class TimeTable extends Frame {
private Frame frame;
public TimeTable(){
setupGUI();
}
private void setupGUI(){
frame = new Frame("TimeTable");
frame.setSize(400, 400);
frame.addWindowListener(new WindowAdapter(){
public void wndClose(WindowEvent wndEvent){
System.exit(0);
}
});
frame.setVisible(true);
}
public static void main(String[] args){
TimeTable timetable = new TimeTable();
}
}
It should be a little GUI (AWT) Test-Window.
I build it with:
>> javac TimeTable.java
And run it with:
>> java TimeTable
The ICON of the AWT APP is shown in my Launcher Sidebar, but the Window doesn't appears on my Desktop.
Why not?
You can install Java on Ubuntu without graphics libraries (headless?).
Install the standard Java including graphics libraries and it should work. Your code works fine on Windows inside IntelliJ.
Related
I recently decided to upgrade an old Swing application from Java 1.6 to 1.8. Unfortunately, when I build and launch the application under Java 8 the window appears and is empty. If I build and launch under Java 7 or 6 the content displays as expected. Here is a sample code that reproduced my problem:
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class SwingRenderingIssue {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame();
frame.setTitle("hello world");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.add(new JButton("hello again"));
frame.setContentPane(panel);
frame.pack();
frame.setVisible(true);
}
});
}
}
The Java 8 version I have is jdk-8u181-linux-x64.
I have the following swing code :
import java.awt.Dimension;
import java.awt.GraphicsEnvironment;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingUtilities;
public class JFrameDemo {
private JFrame jframe = new JFrame();
public JFrameDemo() {
jframe.setSize(new Dimension(800, 20));
jframe.setUndecorated(true);
jframe.getContentPane().add(new JLabel("xxxxxxxxxxx"));
jframe.setVisible(true);
jframe.setAlwaysOnTop(true);
jframe.setLocation(0, 0);
GraphicsEnvironment env = GraphicsEnvironment.getLocalGraphicsEnvironment();
jframe.setMaximizedBounds(env.getMaximumWindowBounds());
jframe.toFront();
jframe.repaint();
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new JFrameDemo();
}
});
}
}
My jframe window is always on top and also in the top of the screen but when other window from os ,like a browser window, is maximized my jframe overlaps that window .
When any os windows are maximized to be maximized below my jframe window.
you can see:
WRONG Behavior
GOOD Behavior
Since I understood java has no support for that feature so I am asking now if exists any native library which should I load using the jni.
So the behavior that I am looking for can be made using the jna lib: Docking a java application jna on windows
Respected all,
I am making a Swing-application window in ECLIPSE. When I run the program as 'JAVA-Application' the program functions well. However when I try to run the program as "Java_applet" the components like 'command button', 'textbox' are invisible.
I am entirely new to Java. I had previously worked on C#. Kindly please help me.
import java.awt.EventQueue;
import java.applet.*;
import javax.swing.JFrame;
import javax.swing.JRadioButton;
import java.awt.BorderLayout;
public class sa extends Applet{
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
sa window = new sa();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public sa() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 450, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JRadioButton rdbtnNewRadioButton = new JRadioButton("New radio button");
frame.getContentPane().add(rdbtnNewRadioButton, BorderLayout.CENTER);
}
}
You can't just have your class extend Applet and expect that that is all that is necessary for it to behave like a proper Applet. You need to give the class a proper init method and build the GUI from within this method. But most importantly you will need to read an Applet tutorial, any decent tutorial should do. Myself, I'd have my GUI extend JPanel, build the GUI in its constructor, and then I could use this JPanel in a JApplet or JFrame as needed.
As Andrew aptly notes in comment,
I think the OP should also dump the entire 'applet' part of it and develop the JFrame with an idea to launching it from a link using Java Web Start. At least then it would have a better chance for working for users of Chrome and FireFox (which are both planning to remove all support for applets).
I am using JWindow in my project to display a UI that is undecorated and also doesn't appear in the task bar. But, the JWindow always seems to be on top of all other windows. I tried setting the setAlwaysOnTop to false, but it didn't seem to help.
Here's the code that can reproduce the problem :
package test;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.JWindow;
public class Test extends JWindow implements ActionListener {
public Test() {
setSize(300, 300);
setLocationRelativeTo(null);
setAlwaysOnTop(false);
JButton myButton = new JButton("Click Here");
myButton.addActionListener(this);
getContentPane().add(myButton);
setVisible(true);
}
public static void main(String[] args) {
new Test();
}
#Override
public void actionPerformed(ActionEvent e) {
if(e.getActionCommand().equals("Click Here"))
JOptionPane.showMessageDialog(this, "This dialog box appears behind the JWindow!");
}
}
My OS is Linux and I'm using the Oracle JDK 6. Also, while I was testing my app on Windows, I was using JDialog for the UI and it was working fine. But, in Linux JDialog seems to appear in the task bar.
Any help as to how to solve this?
After you set the visibility of the window to True, you send it to the back like this:
setVisible(true);
toBack();
If, later, you want to bring it to the top of the stacking order, you simply call:
toFront();
More details here:
http://docs.oracle.com/javase/6/docs/api/java/awt/Window.html#toBack()
http://docs.oracle.com/javase/6/docs/api/java/awt/Window.html#toFront()
Right, so Ive got an interesting problem here concerning SWT and swing integration on mac running java 1.7. Im trying to embed an SWT Browser widget into my swing project as a panel which is pretty simple to do on java version 1.6. There has been a number of posts which explain how to do this with SWT_AWT bridge classes along with the following example:
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.EventQueue;
import java.awt.FlowLayout;
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;
import org.eclipse.swt.SWT;
import org.eclipse.swt.awt.SWT_AWT;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
public class MySWTBrowserTest implements ActionListener {
public JButton addCodeButton;
public JButton launchBrowserButton;
public JTextField inputCode;
public JFrame frame;
static Display display;
static boolean exit;
public MySWTBrowserTest() {
frame = new JFrame("Main Window");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new FlowLayout());
inputCode = new JTextField(15);
inputCode.setText("999");
addCodeButton = new JButton("Add Code");
addCodeButton.addActionListener(this);
addCodeButton.setActionCommand("addcode");
launchBrowserButton = new JButton("Launch Browser");
launchBrowserButton.addActionListener(this);
launchBrowserButton.setActionCommand("launchbrowser");
mainPanel.add(inputCode);
mainPanel.add(addCodeButton);
mainPanel.add(launchBrowserButton);
frame.getContentPane().add(mainPanel, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equals("addcode")) {
} else if (e.getActionCommand().equals("launchbrowser")) {
createAndShowBrowser();
}
}
public void createAndShowBrowser() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final Canvas canvas = new Canvas();
f.setSize(850, 650);
f.getContentPane().add(canvas);
f.setVisible(true);
display.asyncExec(new Runnable() {
#Override
public void run() {
Shell shell = SWT_AWT.new_Shell(display, canvas);
shell.setSize(800, 600);
Browser browser = new Browser(shell, SWT.NONE);
browser.setLayoutData(new GridData(GridData.FILL_BOTH));
browser.setSize(800, 600);
browser.setUrl("http://www.google.com");
shell.open();
}
});
}
public static void main(String args[]) {
//SWT_AWT.embeddedFrameClass = "sun.lwawt.macosx.CEmbeddedFrame";
display = new Display();
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
MySWTBrowserTest mySWTBrowserTest = new MySWTBrowserTest();
}
});
while (!exit) {
if (!display.readAndDispatch()) {
display.sleep();
}
}
display.dispose();
}
}
Im using the swt-3.8M5-cocoa-macosx-x86_64 JAR files which obviously need to be included to run the above example. When using both the 32 bit and 64 bit versions of the 1.6 JDK, this runs perfectly fine, but when switching to the JDK 1.7 or 1.8 VM the reproducible error is thrown:
2012-05-14 15:11:30.534 java[1514:707] Cocoa AWT: Apple AWT Java VM was loaded on first thread -- can't start AWT. (
0 liblwawt.dylib 0x00000008db728ad0 JNI_OnLoad + 468
1 libjava.dylib 0x00000001015526f1 Java_java_lang_ClassLoader_00024NativeLibrary_load + 207
2 ??? 0x00000001015a4f90 0x0 + 4317663120
)
_NSJVMLoadLibrary: NSAddLibrary failed for /libjawt.dylib
JavaVM FATAL: lookup of function JAWT_GetAWT failed. Exit
Java Result: 255
Ive inspected the java 1.7 vm and did find the libraries there, so Im struggling to see what could cause it to not load that library. Of course I make sure to use: -XstartOnFirstThread as one of the VM parameters, as is required for the SWING/AWT integration.
On a further note, I have tried the DJ Native Widgets framework, and it throws the exact same error as it also uses the underlying SWT framework.
To reproduce the effects i suggest installing JDK 1.7 (release not the developer preview) on mac, downloading the: http://www.eclipse.org/downloads/download.php?file=/eclipse/downloads/drops4/S-4.2M7-201205031800/swt-S-4.2M7-201205031800-cocoa-macosx-x86_64.zip to get the library and then running it with the -XstartOnFirstThread -d64 java 1.7 vm.
really hoping someone has been able to sort this out as Im sure Im not the only one trying to integrate SWT into swing on the 1.7 vm
I also spent 8 hours on google to see if this error has been reproduced anywhere else, and it has come up on a few Matlab mailing lists, but other than that I haven't been able to find something even close to a solution.
Thanks in advance.
>> UPDATE 1
Looks like we may have a winner: https://bugs.eclipse.org/bugs/show_bug.cgi?id=374199
Going to monitor this and see where it goes.
>> UPDATE 2
Here is a working example: https://stackoverflow.com/a/27754819/363573
Unfortunately there's no good answer to this. In Java 7 the AWT has been completely rewritten to use CoreAnimation layers. The SWT assumes that an AWT Canvas will be backed by an NSView but that's no longer the case. Your only choice right now is to stick with Java 6.
The AWT team is aware of the problem but you may want to file another bug on bugs.sun.com.