JApplets and JDialog - java

I have a japplet which contains an "about" button, which when pressed creates a new JDialog. The idea is that when the user clicks on the about button in the applet they will get a popup window which displays information. This works perfectly fine when i test it from eclipse with the applet viewer, but when i test it in the html form, the button does nothing. The applet runs and works, but the button does not create a new window or respond in any way.
full disclosure: when i say JDialog i actually mean a class i created which extends JDialog and has a method public void paintComponent (Graphics g){ ~~~~ } ... and i also tried with that class extending JFrame instead and had the same problem, it worked in applet viewer but not in the browser.
now my question is, is my thinking wrong, am i going about creating a popup window for a japplet the wrong way, is there a different method i should probably try?
my code is very long, but if there's something you need to see from it to properly answer the question let me know.

Are you making sure to set the new popup window to visible? That could be your problem, or I've heard of problems with Google toolbar not allowing user-initiated popups to appear, but I think that problem was fixed (if you're running an old version of Google toolbar, it may still be an issue).

ok i figure out what the problem is, is an image problem, the DrawingBoard was using io and imageio to load some images.

Related

NetBeans - How to show all Swing components in a JFrame?

I'm making a Swing GUI with NetBeans, using the built-in form maker, which works quite well.
However, if I accidentally put the wrong panel on a form, I have no way to delete it, or select it again.
Likewise, if I want a button to open a new window, say, a file chooser, I don't know how to add that file chooser to the form, but not have it appear until the button is pressed.
Does anyone have any experience with the NetBeans Swing form builder? This seems like a common thing to have to do, but I don't see how to do it. Am I missing something?
Yay a netbeans user!Yea there should be a navigator window in the bottom left corner. There it displays all of the components on the form. Im not too sure what you mean by a file chooser, but to open a new window,ie another Jform, you create another form class. Then you create that form and setVisible.
So lets say you have
a form mainProgram
And form helpMenu
In the mainProgram
public mainProgram(){
InitComponents();//or something on the lines of that
helpMenu helpMenuWindow = new helpMenuWindow();
helpMenu.setVisible(true);
}
This will allow you to be able to open new windows, but if you click on the red X to close the window, it closes your whole program. In properties for the helpMenu pane you can select the option for what the window should do on exit.
Exit
Hide
Do nothing
In the code above is the code that is run before the Jpane displays, if you want to show or hide items, just code
Object.setVisible(boolean);
I hope I answered your question Tetramputechture.

Exiting out of one of two JFrame exits out of both

I have two seperate JFrames but when i click the X in the topright of one, it will exit out of the other also. I have an "exit" button near the bottom to do setVisible(false), but i still have the tendency to use the x button. How would i make it so that it doesnt cancel out of the entire project?
Also, how would i make it so that the second JFrame locks out of the other JFrame untill the second JFrame is closed, like how a popup message works
Don't give your GUI two JFrames. The GUI ideally should have only one GUI. If a separate window is required, then make it a dialog such as a JDialog, and this won't happen.
Also, how would i make it so that the second JFrame locks out of the other JFrame untill the second JFrame is closed, like how a popup message works
You are perfectly describing the behavior of a modal JDialog or JOptionPane. Just use 'em.
Later we'll chat about using CardLayouts to swap views in a single GUI.
Edit, you state:
Im using Netbeans form editor to create them faster but I only see JFrame and JPanel. Can I edit them in Netbeans? I'd rather not do them through scratch Java
You've touched on another zealous belief of mine, that this is yet another reason not to use a code generator when learning a library as one can get too tied into the code generator, that it prevents one from learning the library. I strongly advise you to put aside your code-generation tool and create by hand, referring to the tutorials and API. Then later when you get more familiar with the library, sure use the tool. By the way, an answer to your direct question here is to gear your GUI's to create JPanels, and then use these JPanels where and how you want them -- in JFrames, or JDialogs, or JOptionPanes, or swapped in CardLayouts, or JTabbedPanes or nested in other JPanels,... etc...
You should be using a modal JDialog, not a second JFrame, because JDialogs provide certain functionality such as not adding another window bar to the taskbar, and automatically setting focus when the parent JFrame receives focus. Modal JDialogs prevent user input to the JFrame while it's open, useful for an "Are you sure you want to exit?" dialog, for example.
As for one JFrame exiting the other, you probably have their default close operation set to EXIT_ON_CLOSE. If you do this:
jframe.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
jframe.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent we){
handleUserWantsToCloseWindow();
}
});
Then you can control what happens when the user wants to close, such as popping up a "Save Changes?" modal JDialog or "Are you sure you want to quit?" modal JDialog. Note that you have to manually dispose of the JFrame if you use this method.

java JFrame setSize

I am loading a JFrame showing the company logo and credits etc before starting the main application. I am having some problems. Fist of all, the size of my new JFrame can never be set. The JFrame looked fine when I previewed it under netBean but came out smaller every time. I tried to do it with a new constructor and setSize(), but still not working. Second, the JFrame has been loaded very slowly. No images and everything could be loaded and the JFrame stays blank for at least five seconds, really kind of annoying. Do it have anything to do with where I put the image files?
Thanks alot.
I am loading a JFrame showing the company logo and credits etc before starting the main application. I am having some problems. Fist of all, the size of my new JFrame can never be set. The JFrame looked fine when I previewed it under netBean but came out smaller every time. I tried to do it with a new constructor and setSize(), but still not working.
It is very difficult to suss out what is wrong without seeing your code, but having said that, your comment about this being a NetBeans-generated GUI suggests that the code will be very large and hard to read and interpret. It is for this and many other reasons that I am not a fan of using NetBeans to generate GUI's, especially for newbies who are just learning how to use Swing. I suggest that you write out your GUI code by hand with some user-friendly layout managers, nested by nesting JPanels if necessary. If you do it this way, you'll have some greater flexibility and control in the construction of your GUI, and you'll also have readable and debuggable code that you can post here for our assessment and help should it not work out right for you.
Second, the JFrame has been loaded very slowly. No images and everything could be loaded and the JFrame stays blank for at least five seconds, really kind of annoying. Do it have anything to do with where I put the image files? Thanks alot.
This sounds like a threading issue. I'd just load the images for the intro GUI first, then show the intro window, and then in a background thread, load any other resources that the program needs.
Having said all this, you probably want to look into using Java's own splash screen as this may do all that you're trying to cobble together on your own. The tutorials can help you with this (please click on link above or here).
Much unclear question description though I want to point some tips...
Do it have anything to do with where I put the image files?
If you mean your JFrame title image so you can use its setIconImage() method
Fist of all, the size of my new JFrame can never be set.
It is quite strange :( because you can always write code like a
JFrame aFrame=new JFrame();
aFrame.setSize(x,y);
... to control your frame scale
Second, the JFrame has been loaded very slowly. No images and
everything could be loaded and the JFrame stays blank for at least
five seconds
It may be caused by single thread overloaded but still to analyze the problem show the main class code or its exceptions stack trace
previewed it under netBean but came out smaller every time
what component do you use to paint your logo? And how do you paint it? Show the snippet
You can set the size by right click on the jFrame and
Set Default size
(netbeans design view)
I hope this is what you want
this may be useful for you?
JPanel aa = new JPanel(new GridBagLayout());
aa.setMaximumSize(new Dimension(500,500));
aa.setMinimumSize(new Dimension(490,490));
aa.setBorder(BorderFactory.createLineBorder(Color.black));
I opened the properties dialog for my JFrame and set "minimum size" field to [500,500] but that did not work.
What did work for me was selecting the "..." button at the right of the "minimum size" property. In the "JFrame Mininumsize" dialog as follows:
set dropdown (Set forms minimum size property using: ) = "Custom Code"
set code in (Form.setMinimumSize( ) ) = "new Dimensiom(500,500)"

Link between two JFrames

Link between two JFrame using JMenu
I have an application where I have to move to another frame by clicking a menu. for example, on a file menu, I click on add which will bring out a new frame where operations can be carried out. what code(s) can i use in Netbeans?
I used it to open another JFrame but when I exit the new JFrame both frames are closed ....
there is something wrong in ma code plz help me in that prob....
You have to set the defaultCloseOperation to something else then EXIT_ON_CLOSE. Please refer to the documentation for JFrame for more information. I suspect that the second JFrame should only have HIDE_ON_CLOSE though.
do you need to use jframes? why not jdialogs? (the dialog window (which can pop up) does not have to be modal.
if you have two different frames, that can make parentage (which window belongs to which frame) something you need to keep track of more assiduously.
please tell us in more detail what you are trying to accomplish; that will help in picking the correct widgets to be used. if things are hard to do/code in swing, then there's probably an easier way with other widgets/components, imho.
good luck!

Working with frames and Java AWT

I am currently making a program with the AWT GUI and I'm running into a problem. I basically want an image in the top left hand corner of the screen, and a column of buttons on the right of the image. This isn't what's happening though. When I run the applet, I click a popup saying "Start Program" and then the picture I want is in the applet window itself and the column of buttons is in another window by itself. This is what it looks like:
Is there anyway to fix this so that the image and the buttons are in the same window?
Yeah. You're creating a frame but your graphic isn't inside the frame. Can't tell much without the code, but the AWT Tutorial at java.sun.com isn't bad on this stuff.
Okay, a little more (I haven't used AWT in a long time.)
Here's the couple of issues you have. A Frame is a kind of Window -- it wants to be a separate window with its own close button and so forth.
When you create your graphic, you have to tell it was component its parent is; you're somehow parenting it to the Applet. So you have some piece of code that looks like
add(myComponent);
in the context of the Applet as this.
public class myApplet extends Applet {
// lots of stuff here creating your canvas, putting the image in it
// and so forth. There's an example, see fn 1.
// When you're done, you have a component, call it myImage.
add(myImage);
}
You have a Frame, and you're adding your buttons to that.
public class MyFrame extends Frame {
add(new Button(...));
add(new Button(...));
}
You need to move the code that adds your Canvas into the Frame class in some method.
(WARNING: this is not complete Java code, I don't recall the names of the right methods offhand. Probably the init() method in the Applet, at least.
fn1. http://java.sun.com/developer/onlineTraining/awt/contents.html#simpleexample

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