I am trying to create a simple menu for a small project using a JSpinner and JOptionPane. I created my desired output, but when I interact with the window or even hover over the buttons in the box, it creates visual artifacts over and over again (see images below):
JOptionPane before mouse hover
JOptionPane after mouse hover
I did some researching and thought it might be due to JOptionPane not being thread safe, but could not get anything to work.
Overall, my specific question is how do I prevent Java from repainting these visual artifacts over my JOptionPane window?
For reference, please see the method I am using to show this menu:
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.SpinnerNumberModel;
import javax.swing.JSpinner;
public class Battleship
{
public static void main(String[] args)
{
SpinnerNumberModel battleshipRange = new SpinnerNumberModel(1, 1, 5, 1);
JSpinner rangeSpinner = new JSpinner(battleshipRange);
JOptionPane.showMessageDialog(null, rangeSpinner, "Battleship Number", JOptionPane.QUESTION_MESSAGE);
}
}
I am running this code on BlueJ and am using Windows 10 Pro.
Thank you in advance and apologies if this is a beginner question. I am still fairly new to programming.
EDIT: Updated code to give complete source of problem, but it disappeared. I will keep an eye on it to see where the source of the error first occurred.
After completing my project, I finally found why visual artifacts would pop up in all buttons/radio buttons/etc. in my game.
In the GridWorld source code, under the "GridPanel.java" script, the original programmers created a method called "setToolTipsEnabled(boolean flag)". Its function is to pop up a message box next to the cursor when it is hovering over the grid when the game stops running.
When extending GridWorld to create my project, the method reaches past the grid structure and attempts to create a tool tip underneath anything the cursor hovers over. Thus, creating visual artifacts on buttons/radio buttons/etc.
To fix this, I made sure this method was always set to false as I did not need tool tips for my game anyway. This method was implemented in the "GridPanel.java" and "GUIController.java" scripts (in the GridWorld code). I changed following methods to fix this problem:
GridPanel.java
/**
* Construct a new GridPanel object with no grid. The view will be
* empty.
*/
public GridPanel(DisplayMap map, ResourceBundle res)
{
displayMap = map;
resources = res;
// Phillip Sturtevant: Commented out to prevent visual artifacts
//setToolTipsEnabled(true);
}
GUIController.java
/**
* Stops any existing timer currently carrying out steps.
* Phillip Sturtevant Note: keep tool tips hidden to prevent visual artifacts
*/
public void stop()
{
display.setToolTipsEnabled(false); // hide tool tips while stopped
timer.stop();
running = false;
}
Alternatively, the method calls could be omitted entirely, but I commented them out in case I needed them in the future.
For reference, the method below sets the tool tips visibility in GridWorld (located in "GridPanel.java"):
/**
* Enables/disables showing of tooltip giving information about the
* occupant beneath the mouse.
* #param flag true/false to enable/disable tool tips
*/
public void setToolTipsEnabled(boolean flag)
{
if ("hide".equals(System.getProperty("gridworld.gui.tooltips")))
flag = false;
if (flag)
ToolTipManager.sharedInstance().registerComponent(this);
else
ToolTipManager.sharedInstance().unregisterComponent(this);
toolTipsEnabled = flag;
}
Related
I’ve trimmed down the code to only the relevant parts and posted it below. The code works fine. The video plays when you run it but it doesn’t have a seekbar.
public class Screen {
//JFrmae
private JFrame frame;
// Panel which I add the canvas to
private JPanel pVid = new JPanel();
// Canvas
Canvas canvas = new Canvas();
// Embedded Media Player
EmbeddedMediaPlayer emp;
/**
* Create the application.
*/
public Screen() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
//Frame
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
//Adding the panel to the frame
frame.getContentPane().add(pVid);
//Adding the canvas to the panel
pVid.add(canvas);
//Setting canvas size
canvas.setSize(715, 402);
//Loading the VLC native library
NativeLibrary.addSearchPath(RuntimeUtil.getLibVlcLibraryName(), "lib");
Native.loadLibrary(RuntimeUtil.getLibVlcLibraryName(), LibVlc.class);
//Initializing the media player
MediaPlayerFactory mpf = new MediaPlayerFactory();
//Misc
emp = mpf.newEmbeddedMediaPlayer(new Win32FullScreenStrategy(frame));
emp.setVideoSurface(mpf.newVideoSurface(canvas));
//Video file name and playing
String file = "video.mp4";
emp.prepareMedia(file);
emp.play();
//pack method
frame.pack();
}
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Screen window = new Screen();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}
I’ve looked for an answer online for the last 4 days. Finally I decided to ask here. The official website for vlcj has pictures of a vlcj player they’ve made. There is a seekbar in those pictures. Link to the webpage which has the pics: http://capricasoftware.co.uk/#/projects/vlcj
They have a number of useful tutorials there but they don’t have any instructions for adding the seekbar.
Then I tried downloading their vlcj-player project from their GitHub page. It showed an error because it couldn’t resolve the “com.google.common.collect.ImmutableList” which is supposed to be imported. (At the moment I’m reading about ImmutableList and stuff and see if there’s a way to fix it.) Since I couldn’t figure that out yet, I looked for a class named seekbar or the like in their project. I couldn’t find any.
I also searched elsewhere online for the answer but I just couldn’t find it. I’d really appreciate any help. Thank you.
Edit:
(This edit is in response to the suggestion given to me by #caprica. Read their comment to this question and my reply to that in the comment to understand what I'm talking about here in this edit. I think it'll be useful for others in the future.)
All right, there must have been some problem with my Eclipse or computer. (I’ll type out how I fixed it at the end of this comment.) It’s working now. I’ll type out what I did step by step so that may be it’ll be useful to others in the future to download and install the project.
Download the project.
Import it as a Maven project. (Import > Maven > Existing Maven Project)
Now in Eclipse right click the imported project and select Run As > Maven Install
And that’s it. Now you can just run the project normally. If you don’t know how to run the project, do it like this. Right click the project and select Run As > Java Application and then Select VlcjPlayer – uk.co.caprica.vlcplayer.
Alternatively you can open the class where the main method is and run it. VlcjPlayer class is where the main method is located. The class is in the package uk.co.caprica.vlcplayer.
The problem I faced was that somehow all the necessary files didn’t get downloaded when I ran it as Maven Install. But it worked fine in another computer. Since I knew where the files are downloaded to, I just copied the folder from that PC and put it in the same place in my PC. The folder name is ‘repository’. It’s location is C:\Users\User Name\ .m2. Perhaps Eclipse in this PC has some problem. I’ll reinstall it later to avoid problems in the future.
And this may be useful, the VLC that’s installed in this PC is 64 bit. Not sure if that makes a difference but mentioning it just in case.
Now that the app is working fine I will see the code and see how the seekbar is made. Thanks a lot #caprica for telling me that I should import it as a Maven project. :)
The Basic Controls tutorial shows the essential approach: Add a panel of buttons to the frame and give each button an ActionListener that invokes the relevant media player command. As an example, this notional Rewind button would "skip backwards 10 seconds (-10,000 milliseconds)."
JPanel controlsPane = new JPanel();
JButton rewindButton = new JButton("Rewind");
rewindButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
mediaPlayerComponent.getMediaPlayer().skip(-10000);
}
});
controlsPane.add(rewindButton);
frame.add(controlsPane, BorderLayout.SOUTH);
The software design is up to you, but you should at least be aware of
JToolBar, seen here and here.
Action, seen here and cited here.
Timer, seen here as a way to repeat an Action.
All right, guys. I’ve figured out how to do it. I’m not sure how it was done in the official Vlcj project but I’ve figured out my own simple way by learning from the official project.
It just takes a few lines of code. It’s very simple.
These are the steps you have to follow:
Create a JSlider.
To the JSlider, add a mouseMotionListener (‘mouseDragged’ to be exact).
Inside that put in the code which would update the video position based on
the change in the JSlider.
Create a Timer.
Put the code inside it to set the value of the JSlider based on the position
of the video.
And that’s it!
This is the code. It comes inside the initialize() method which you can see in the code I’ve given in the question. (And of course you'll also have to create the JSlider and add it to the panel. I haven't shown the code since it's simple.)
js.addMouseMotionListener(new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent e) {
if (js.getValue() / 100 < 1) {
emp.setPosition((float) js.getValue() / 100);
}
}
});
Timer timer = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
js.setValue(Math.round(emp.getPosition() * 100));
}
});
timer.start();
Some explanation.
The value you get when you use emp.getPosition always seems to be in decimals. It’s something like 0.1334344 at the start of the video and it’s something like 0.998988 at the end. But the value of JSlider is in int. From 0 to 100. So in the mouseMotionListener added to the JSlider I’ve converted the int value of the JSlider to float by dividing it by 100.
And in the action listener inside the timer I’ve multiplied the value of the video position by 100 and then rounded it off to make it an int value. So that value can be set in the JSlider to make it move in sync with the video.
I’m sure the code is rudimentary and there could be some best practices which I may not have followed. Sorry about that but I’m just getting into java by learning the stuff which I find interesting. Those who are good at java and have used such code in an actual project can comment below with how it can be improved.
I am trying to set the default close operation in NetBeans 8.0.2 (in Ubuntu 14.04 on an older Asus gaming laptop.) My program is very large but uses no JFrame or java.swing components.
I merely need to save some values when the "x" in the lower right corner is clicked (this is one usual way to stop execution of a java program in NetBeans.)
I found suggestions that involved swing & JFrame, but it wasn't clear just where to insert the code:
DefaultApplicationView view = new DefaultApplicationView(this);
javax.swing.JFrame frame = view.getFrame();
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.addWindowListener(new WindowAdapter(){
public void WindowClosing(WindowEvent e){
System.out.println("CLOSING");
}
}
show(view);
I also found a set of instructions that I think I would prefer to use, but the post is old enough that my NetBeans doesn't have the tabs/menu-items referred to:
Set Window to Design Mode by clicking the 'Design' Tab
In the Navigator: Right click the 'JFrame' -> 'Properties'
In the Properties Tab: Set 'defaultCloseOperation' (top of the list) to 'DO_NOTHING'
Select 'Events' Tab
Scroll down to 'windowClosing'
Click on the "..." button on the right of the event to bring up the custom editor
Click 'Add...' and name the handler (i.e. custom function that you want to have execute on click of the 'X', or window close event).
Click 'Ok'
Netbeans now automatically creates the function and takes to you the function body in the source view
Now simply add what you want to do here: eg. dispose(), or system.exit or pintln(), or whatever your heart desires, as long as its JAVA and makes sense to the app.
Then there are a few other possibly relevant posts, but they all explicitly involve JFrame and/or swing. (Am I ignorant of some fact such as "All NetBeans java applications use JFrame", or some such?)
A pared down example of code for what I'm trying to do would be:
public class MyApp{
public static void main(String[] args){
loadMyVariables();
// do some work that changes variables' values
// during this work user clicks the 'x' box to halt execution
// I need then automatically to save the variables' new values
}
// needs to be called by the OS or GUI when execution is halted by user
public static void saveMyVariables{
// here the usual printStream stuff saves some values to a file
System.exit(0);
}
public static void loadMyVariables{
// here the usual Scanner stuff reads some values from a file
}
}
(I need help setting the tags for this, so I'm doing as instructed and asking the community.)
THANKS
My application works on tablet (with Windows 7) which sometimes turns off its display in order to save battery. After touching the screen, it turns on again.
Application should remain operational even after turning off the screen, what is, in general, accomplished (i.e. sounds are played). The only problem is the fact that when screen is turned off and application tries to add new component to the scene (technically - add children to the displayed GridPane), the newly added component is not visible when I touch the screen (and it turns on).
It is just like there was a cache which stores and restores displayed content when screen is turning on/off. After turning screen on - when I click windows button (keyboard) or or change focus to another application - newly added component appears.
I have tried setting -Dprism.dirtyopts=false but it did not change anything.
My Java is 7u67.
Is it known bug? Is there any programming workaround? I have tought about using WinAPI to force redraw/refresh of the application window but it seems too big for this case.
I have just figured out "simple" workaround:
import com.sun.jna.Pointer;
import com.sun.jna.platform.win32.Kernel32;
import com.sun.jna.platform.win32.User32;
import com.sun.jna.platform.win32.WinDef;
import com.sun.jna.platform.win32.WinUser;
import com.sun.jna.ptr.IntByReference;
/** WINAPI CONSTANTS **/
private static final int RDW_UPDATENOW = 0x0100;
/**
* Redraws all windows associated with currently running process.
*/
public static void redrawApplicationWindows() {
final int processId = Kernel32.INSTANCE.GetCurrentProcessId();
User32.INSTANCE.EnumWindows(
new WinUser.WNDENUMPROC() {
#Override
public boolean callback(WinDef.HWND hwnd, Pointer pointer) {
IntByReference someProcessId = new IntByReference();
User32.INSTANCE.GetWindowThreadProcessId(hwnd, someProcessId);
if (someProcessId.getValue() == processId) {
User32.INSTANCE.RedrawWindow(hwnd, null, null, new User32.DWORD(RDW_UPDATENOW));
}
return true;
}
}, Pointer.NULL);
}
It requires you to have jna and jna-platform in dependencies.
This method should be called after drawing when the screen is turned off (it is another problem how to detect it). As my application rarely draws automatically (without user input), I have placed its call after every drawing happening automatically.
It works in Win7.
I have 2 classes, and each one of them has a launcher for a form that utilizes them:
DateTester uses DateTest class and is launched by dateLauncher
CylinderTest uses Cylinder class and is launched by cylLauncher
each launcher is simply comprised of
Cylinder program = new Cylinder();
respectively. They both launched fine by themselves. What I would like to do is create a launcher window (just a pane with two buttons) that will launch either program when their buttons is clicked. I just moved everything into the same package (although im thinking that I shouldnt have done that now), and now neither will launch from their respective launcher. I was trying to launch them with something like:
public void actionPerformed(ActionEvent ev)
{
if(ev.getSource() == btnCylinder)
{
Cylinder prgCylinder = new Cylinder();
}
else if (ev.getSource() == btnDate)
{
DateTester prgDate = new DateTester();
}
else{}
}
but it doesnt do anything. I also tried threading them, and that didnt work either. Any suggestions? Or is this actually a lot more complicated than it seems?
turns out it was just the action listener not added for the buttons. paulo answered this in a comment, but i need to close this as answered. thanks paulo.
i have this problem with my project these days. i'm developing a plugin in eclipse,
i need to write a text on the active window(coding area) when i click a button.
i use the following code in my button.java class
public class Button implements IWorkbenchWindowActionDelegate {
private IWorkbenchWindow window;
/**
* The constructor.
*/
public Button() {
}
/**
* The action has been activated. The argument of the
* method represents the 'real' action sitting
* in the workbench UI.
* #see IWorkbenchWindowActionDelegate#run
*/
public void run(IAction action) {
MessageDialog.openInformation(
window.getShell(),
"Button",
"Code of the Button goes here");
}
how can i do it inside the run method? here I'm displaying a message, instead of showing a message i want to display some text in the text editor pane. please help me to achieve this.
if you guys can please give me some links to understand about eclipse plug-in developments? any blog posts that are easy to understand will be much better?
You should do something like this. It is completely untested and you will need to add lots of null checks and try-catch blocks, but the code below gets the currently active editor and replaces the current selection with whatever is passed in as an argument:
void method (String text) {
IEditorPart part = Workbench.getInstance().getWorkbenchWindows()[0].getActivePage().getActiveEditor();
IEditorInput editorInput = part.getEditorInput();
if (part instanceof ITextEditor) {
ITextEditor textEditor = (ITextEditor) part;
IDocument doc = textEditor.getDocumentProvider().getDocument(editorInput);
ITextSelection sel = textEditor.getSelectionProvider().getSelection();
doc.replace(sel.getOffset(), sel.getLength(), text);
}
}
It is messy and complicated, but that's the Eclipse framework for you.
This might be a good place for you to look at Eclipse plugin development:
http://www.ibm.com/developerworks/views/opensource/libraryview.jsp?search_by=Create+commercial-quality+eclipse+ide
Developer Works in general has a lot of good content on Eclipse, so if this series is not exactly what you need, you can explore Developer Works for other things.
I'd recommend this one. It is a very good introductory tutorial