How to prevent multiple instances of MDI child forms in netbeans - java

Im developing a java app with MDI application forms. I have assigned menu items to open two internal child forms. when i click them repetitively they create instances for each click how can i stop this and show the previously instantiated form at the first click.
here is the code for the action listener for the menu item im using,
private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
RecognitionForm recForm=new RecognitionForm();
desktopPane.add(recForm);
recForm.setVisible(true);
}

I can think of two ways.
The first is to raise a flag when you create the frames. The problem here is the fact that you will need to monitor for when the frames are closed, which adds additional overhead.
The second is to check all the frames currently open on the desktop for the instance of the frame, using `JDesktopPane#getAllFrames'.
From there you would simply loop through the result doing either a instanceof of comparing the title (for example) and if you don't find any, create them, otherwise you could use JDesktopPane.selectFrame to highlight it

Give all your MDI child internal frame a distinct name
Put the below code before your code RecognitionForm recForm=new RecognitionForm();
//start code
javax.swing.JInternalFrame[] frames = jDPane1.getAllFrames();
for (int i = 0; i < frames.length; i++) {
javax.swing.JInternalFrame f = frames[i];
if (f.getName() == "yourInternalFramename") {
return;
}
}

Related

Dispose frame In Its Constructor

I want to dispose a frame in its constructor when the condition is true.
this.dispose is not disposing frame. I want that, when my constructor is called, if condition i.e (configurationBean.getCode().equals(macPass)) is true then a new frame have to be called and this frame must have to be closed. Else this frame have to be created.
public ConfigurationFrame() {
String pcMac = getPcMacAddress();
String macPass = getPassword(pcMac);
ConfigurationDao configurationDao = new ConfigurationDaoImpl();
ConfigurationBean configurationBean = configurationDao.checkCode(macPass);
if(configurationBean == null)
initComponents();
else if(configurationBean.getCode().equals(macPass))
{
new MainLoginFrame().setVisible(true);
this.dispose();
super.setVisible(false);
}
}
}
Note that your question is a classic "XY Problem" type question where you ask "how do I do X", when the best solution is "Don't do X but instead do Y". In other words you definitely do not want to dispose of a top-level window object such as a JFrame in its constructor as you're trying to do.
I think that what you want to do (a guess) is to
Test the configuration of things
If OK, display the main GUI
If not OK, then display a window that allows the user to re-set the configuration
Key point: then re-test if the configuration is OK,
And if so, then display main GUI
Repeat as necessary.
If so, then I would use a while loop to show the set configuration window and exit the loop if the configuration is OK, but also allow the user to exit the loop if they simply want to quit or can't set the configuration OK. Something like this:
// configurationGood: true if config is good
// justQuit: true if the user has had enough and wants to quit
while (!configurationGood && !justQuit) {
// create configuration dialog here
// calling constructors, and all
// use a **modal** dialog here
// change configurationGood and/or justQuit values in here
}
if (!justQuit) {
// create and display main application here
}
Note that
this code is not called within any GUI window constructor, but rather prior to displaying the GUI
The re-set configuration window shouldn't be a JFrame but rather a modal JDialog
This way the program code flow halts while the dialog is displayed and only resumes after the dialog has been dealt with.
This allows the code within the while loop to query the dialog the state of its fields and use this to re-test that the configuration is OK

How to perform custom navigation through JFace Eclipse Wizard pages?

I have Eclipse JFace wizard with five pages. In the first, I have check buttons to select which pages are to be shown - if you check all, you will pass through the whole wizard, but you can also select only specific pages, and then only that pages will be shown.
So far, I used iterator with enum objects representing each page. I called next object of iterator in getNextPage function and its if..else cases to return certain pages in proper order. The problem is, getNextPage is called not only when Next button is pressed, but also when pageComplete event firing, etc. so iterator does not update its cursor when I want, and it ends up to fast. This is snippet of my assumption:
else if(page == FirstPage )
{
// iterator contains SelectedAction - enum objects representing pages
this.pageIterator = page.getWizardPagesList().iterator();
if(pageIterator.hasNext())
{
return selectedActionToPage(pageIterator.next());
}
}
else
{
if(pageIterator.hasNext())
{
SelectedAction action = pageIterator.next();
if(!pageIterator.hasNext())
{
// we check if current page was last one
setFinished(true);
setLastPage(selectedActionToPage(action));
}
// selectedActionToPage converts enum object to WizardPage class
return selectedActionToPage(action);
}
else if((pageIterator != null) && !pageIterator.hasNext())
{
return page;
}
}
return page;
Especially, things I want to know are:
First, is there any other way to capture Next button click? I know there is NextPressed method in WizardDialog class, but I don't know how to call its instance from my Wizard class, or WizardPage.
Second, is there other way to customize navigation through pages, to go to specified pages?
No, you should not try to intercept the Next button click that logic is private to the wizard dialog and you should not be trying to interfere with it,
You can either override the WizardPage:
public IWizardPage getNextPage()
method or you can override the Wizard
public IWizardPage getNextPage(IWizardPage page)
You may also need to override the matching getPreviousPage method. You must make your code work regardless of when the method is called. You are given the information about which is the current page, your code should use that to determine the next page.

netbeans setDefaultCloseOperation

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

How to create controls dynamically in JFace Wizard

I have a jFace wizard, I am using this to create a new project type eclipse plugin. As you can see from image below, I have one treeviewer on left side, and a SWT group on right side. What I want is when ever user selects one of the item from treeviewer, I should be able to create dynamic controls on right side SWT Group. Say user selects Test One, one right side I should be able to create few controls like label, text and few radio buttons on right side, similarly if user selects Test Two I should be able to create dynamic controls on right side.
Currently I tried below code:
tree.addSelectionListener(new SelectionAdapter() {
#Override
public void widgetSelected(SelectionEvent e) {
for (int i = 0; i < selection.length; i++) {
String tempStr = selection[i].toString();
tempStr = tempStr.replaceAll("TreeItem \\{", "");
String finalStr = tempStr.replaceAll("\\}", "");
if (finalStr.equals("Test One")) {
Button btn = new Button(g2, SWT.NONE); //g2 is right side group
btn.setText("Blaaaa");
btn.setVisible(true);
container.redraw();
}
}
But when I run, I see no changes on right group. Can anyone guide me what I am doing wrong? Any pointers would be very appreciated, since I am new to Eclipse development and SWT.
You probably didn't set a layout on the g2 group. This is the common cause for controls not showing up. You can also try using g2.layout() to ensure that the new controls are correctly laid out after you create them.
Additionally you could look at using a StackLayout so that once you create a set of controls you can just hide them all at once instead of destroying when the selection changes. This is often useful so that if the user comes back to a previous selection, they will find the data they entered in the same state when they switched the selection. Here is an example.

Wicket panels need page refresh for javascript script to work

I am creating a web page with several tabs. To implement that I am using wicket AjaxTabbedPanel and several AbstractTab. In each tab I have tables with data and I am using a javascript script to make the tables sortable.
public TabbedPage() {
List<ITab> tabs = new ArrayList<ITab>();
tabs.add(new AbstractTab(new Model<String>("first tab")) {
public Panel getPanel(String panelId) {
return new TablePanel(panelId);
}
});
tabs.add(new AbstractTab(new Model<String>("second tab")) {
public Panel getPanel(String panelId) {
return new TablePanel(panelId);
}
});
add(new AjaxTabbedPanel("tabs", tabs));
}
When I load the page the table in the tab selected by default is sortable. However, as soon as I click any of the links to jump to other tabs (including the one of the tab already selected), none of the tables in any of the tabs allows me sort them (including the one that was previously working - the table in the default tab). If I refresh the page I can sort the table (of the tab selected in the moment of the refresh), but as soon as I click in any of links to switch tabs, the tables stop having the sortable capability again. Any ideas of why is this happening?
EDIT:
I just found that if I replace the AjaxTabbedPanel by TabbedPanel I don't have this problem. Although I'm still not sure why is that. Can anyone enlighten me?
add(new TabbedPanel("tabs", tabs));
Sorting the table by JavaScript is most likely a function called with a specific DOM-Id and seems to be executed 'onLoad'. it then accesses the currently displayed table and does it's work.
Changing the content of your Panel by Ajax doesn't trigger 'onLoad' so the function isn't executed again. TabbedPanel reloads the page and therefore executed your script.
Selecting a previous sortable table with AjaxTabbedPanel doesn't work because of the dynamically generated DOM-Ids.
Your solution is to add a AjaxCallDecorator to the links from AjaxTabbedPanel or to include the script or at least the function call to your tabbed panels.
At least this it what comes to mind without seeing any sources...
EDIT:
You might want to look at The Wicket Wiki. There's a description on how to call js after clicking an AjaxLink. That's exactly what should solve your problem.
Summary: Just add
link.add(new AttributeAppender("onclick", new Model("myTableSortingScript();"), ";"));
to the links generated by AjaxTabbedPanel.
In Wicket 6.0 you can run JavaScript on a component basis: Just override renderHead(IHeaderResponse response) for your component:
#Override
public void renderHead(IHeaderResponse response) {
super.renderHead(response);
response.render(new OnLoadHeaderItem("initalizeMe(\"" + getMarkupId() + "\");"));
}
initializeMe(mycomponentId) is executed every time the component is loaded by the AjaxTabbedPanel. This also works with the standard TabbedPanel.
No real idea since I'm not sure what the code is doing but I had a similar problem with my Panel Manager. Basically if you dynamically load HTML into a panel (a div or another element) using "innerhtml" script in the content will not be executed.
To get around this I scan the loaded content for "script" tags and append them using the DOM methods - this does run the script and makes it available. My "load" method is:
// Load Content
Panel.load = function(Content) {
// "null" the old (to clear it)
Panel.innerHTML = null;
// Load the content
Panel.innerHTML = Content;
// Load Scripts
var AllScripts = Panel.getElementsByTagName("script");
var AllScriptsCnt = AllScripts.length;
for (var Cnt = 0; Cnt < AllScriptsCnt; Cnt++){
var CurScript = document.createElement('script');
CurScript.type = "text/javascript";
CurScript.text = AllScripts[Cnt].text;
Panel.appendChild(CurScript);
};
};
Again, not sure if this is the issue, but it sounds pretty much on target from my experience.

Categories

Resources