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JAVA gwt - saving info after refreshing page

At the moment , im working with java gwt and i stopped studdenly because one problem occured. I want that my information (for example string) will save after refresh button is clicked.
// user enters something in TextArea textArea1 object
Window.addWindowClosingHandler(new Window.ClosingHandler() {
public void onWindowClosing(Window.ClosingEvent closingEvent) {
//maybe there is a function or what
pleaseSaveInfomation(textArea1);
}
});
I tried this , but i know how to implement it correctly to my source code:
https://stackoverflow.com/a/14220746/5010218
The last(worst) chance is to store data from textArea in file.txt , after refreshing i could read info from file and thats all. But maybe GWT has a specific handler/method/class or what to handle this.
Thats for your opinion and help.

I had the same problem. You can easily overcome it with this.
import com.google.gwt.storage.client.Storage;
private Storage stockStore = null;
stockStore = Storage.getLocalStorageIfSupported();
Please read documentation
http://www.gwtproject.org/doc/latest/DevGuideHtml5Storage.html#UsingStorage

When a browser close a window (because of a refresh, or the user has closed the window, changed the url, etc), a script is not allowed to prevent this action. It's not specific to GWT.
However, you can suggest to the browser-agent to show a confirmation to the user. You can do this with the message property of the closing event.
In GWT:
Window.addWindowClosingHandler(new Window.ClosingHandler() {
public void onWindowClosing(Window.ClosingEvent closingEvent) {
closingEvent.setMessage("Confirm ?");
}
});
You shouldn't rely on this event to store your data, as a lot of condition can prevent you to do this. You should maybe periodically store a draft to the local-storage or to the server.

You probably want to store your data in sessionStorage. In GWT, this the Storage class.

Custom message when closing a part in Eclipse RCP 4

we have the following problem:
In our Eclipse RCP 4 application there are multiple parts and the parts are closable. When the user is closing a part there should be a custom pop-up (depending on some internal part state) which is asking the user if he really wants to close the part or not.
It seems to be not that easy to implement in Eclipse RCP 4 or we have just totally overseen something.
I'll just give you a short brieifing about the things we tried:
Use dirtable with a #persist method in the part. Though the problem is, we don't want this standard eclipse save dialog. So is there a way to override this?
public int promptToSaveOnClose(): This seemed to be promising but not for Eclipse 4 or is there a way to integrate it that way? Compare: http://e-rcp.blogspot.de/2007/09/prevent-that-rcp-editor-is-closed.html
Our last try was to integrate a custom part listener, simple example shown in the following:
partService.addPartListener(new IPartListener() {
public void partVisible(MPart part) {
}
public void partHidden(MPart part) {
partService.showPart(part, PartState.ACTIVATE);
}
public void partDeactivated(MPart part) {
}
public void partBroughtToTop(MPart part) {
}
public void partActivated(MPart part) {
}
});
The problem with this was we are running into a continuous loop. Something similar is posted over here in the last comment: Detect tab close in Eclipse editor
So I could write some more about this problem, but I think that's enough for the moment. If you need some more input just give me a hint.
Thanks for helping.

The save prompt is generated by the ISaveHandler registered in the context of the MWindow containing the MPart. You can write your own ISaveHandler and set it in the window context to replace the default.
You might also want to look at the IWindowCloseHandler also in the window context.

Thanks greg, this has helped and I was able to achieve changing the pop-up when the user closes a part. Here's a short description of what I've done:
Use the MDirtyable for marking the part as dirty whenever it's needed.
Create a custom save handler which implements ISaveHandler (when a part got closed the save method is called). Add the additional logic to this handler (e.g. a custom message dialog)
Register this handler at application start-up (I just chose a method which is called at the start-up):
#Inject
private MWindow window;
...
ISaveHandler saveHandler = new CustomSaveHandler(shell);
window.getContext().set(ISaveHandler.class, saveHandler);
Note that the registration via a model processor was sadly not that easy because the model processor is called too early. (Take a look at: http://www.eclipse.org/forums/index.php/t/369989/)
The IWindowCloseHandler is just needed when the complete window is closed, though this was not an requirement for us :).

Java jface calling browser from an relative location

I have encountered a small problem that I need some help on. The issue is that I wish to call a browser window which calls a html page. The html file opens in 3 different browsers so the code for that should be correct. The actual problem is that it brings up a page can't be displayed error message
Here is the code that gets the location
package org.error;
public class BrowserLocation {
private String test1 = "org\\error\\PatientNumberError.html";
public BrowserLocation() {
}
public String patientNumberAddress() {
return test1;
}
}
and here is the code that creates the browser component and calls the location of the html file.
Browser browser = new Browser(container, SWT.NONE);
browser.setForeground(SWTResourceManager.getColor(SWT.COLOR_DARK_BLUE));
browser.setBackground(SWTResourceManager.getColor(SWT.COLOR_WHITE));
browser.setUrl(browserLocation.patientNumberAddress());
browser.setBounds(25, 25, 315, 180);
Would it be possible to find the error of my ways?

setUrl require a URL so you need something like:
browser.setUrl(new File(path).toURI().toURL().toString());

Sorry for not getting back to you earlier.
Someone that I know who is a senior Java programmer told me the problem that I was having was a case of absolute address versus relative address.
The reason for this is that if I was reading and writing to a file, then I would be able to use a relative address. However If I'm interacting with a server which is the case here as eventually It could go on-line (If I had the money) it would need to be an absolute address.
As I am still learning Java programming this was a very specific and important lesson to learn. I hope this would help anybody else who has had this issue.

How to use GWT fileupload?

I have some queries when trying to implement a fileupload widget in my application. After many tries, it just doesn't seem to work.
Hence, I tried getting working solutions to see if I can understand anything from there.
http://code.google.com/p/faculty-gwt/source/checkout
However, I tried uploading a file using this and it seems that I am getting error messages too. and what is that textbox and listbox suppose to do? It is meant for showing an example of validating an input before submitting?
Can someone guide me along to solve this? Thanks.

Never tried to use the link you provided, but this is what i did to use a a GWT FileUpload widget:
I built a File Upload widget using the uibinder:
<g:FormPanel ui:field="docForm">
<g:FlowPanel ui:field="inputPane">
/*other displayed info*/
<g:FileUpload ui:field="DocPath"/>
/*other displayed info*/
</g:FlowPanel>
</g:FormPanel>
(Per the GWT api, FileUpload widgets can only be used from a FormPanel)
Make sure you set these in the FormPanel, otherwise you'll probably have issues:
yourFormPanel.setEncoding(FormPanel.ENCODING_MULTIPART);
yourFormPanel.setMethod(FormPanel.METHOD_POST);
That widget is dropped into my container page, then added to the display panel:
private FileUploadWidget createNewUploader(){
FileUploadWidget uploader = new FileUploadWidget(/*my constructor params*/);
uploader.addChangeHandler(new ChangeHandler() {
#Override
public void onChange(ChangeEvent event) {
DocPanel.add(createNewUploader());
}
});
return uploader;
}
My OnChange event is so that I have a new, blank uploader available when i use the current one.
and when I'm ready to submit:
private void processUpload(FileUploadWidget upload, int id) {
upload.setId(id);
//Don't bother to submit an empty one.
if (upload.IsFileSelected())
upload.Submit();
}

Bridge between the Java applet and the text input controls on the web page

I have been working with a Java applet which is an applet that helps to write using only a mouse. For my case, I am trying to incorporate this into my webiste project as follows:
When the user clicks on any input element (textbox/textarea) on the page, this JAVA applet loads on the webpage itself. In the screenshot of the JAVA applet seen below, the user points to an alphabet to and the corresponding text gets written in the text box of the applet.
Now what I am trying to do is to get this text from the TextBox of the applet to the input element on the webpage. I know that this needs an interaction between the Java and JavaScript, but not being a pro, I really do not have the catch. Here's the Java applet and the code I have written.
Java applet and jQuery code (298kB): http://bit.ly/jItN9m
Please could somebdoy help for extending this code.
Thanks a lot!
Update
I searched somewhere and found this -> To get the text inside of Java text box, a getter method in the Applet to retrieve the text:
public class MyApplet extends JApplet {
// ...
public String getTextBoxText() { return myTextBox.getText(); }
}
In the JQuery code, the following lines are to be added I think:
var textBoxText = $("#applet-id")[0].getTextBoxText();
//Now do something with the text
For the code of the applet, I saw a GNOME git page here. The getText call already exists -- look at the bottom of this file: http://git.gnome.org/browse/dasher/tree/java/dasher/applet/JDasherApplet.java
I'd need to call 'getCurrentEditBoxText' but when should this method 'getCurrentEditBoxText' be called?
In my case, I would probably have to do it when the user clicks in a new input control etc.

You can have full communication between your Applet and any javascript method on the page. Kyle has a good post demonstrating how the Javascript can call the applet and request the text value. However, I presume you want the HTML Textfield to update with each mouse click, meaning the applet needs to communicate with the page. I would modify your javascript to something like this:
var activeTextArea = null;
$('textarea, input').click(function() {
$(this).dasher();
activeTextArea = this;
});
function updateText(text) {
// Careful: I think textarea and input have different
// methods for setting the value. Check the
// jQuery documentation
$(activeTextArea).val(text);
}
Assuming you have the source for the applet, you can have it communicate with the above javascript function. Add this import:
import netscape.javascript.JSObject;
And then, in whatever onClick handler you have for the mouse clicks, add:
// After the Applet Text has been updated
JSObject win = null;
try {
win = (JSObject) JSObject.getWindow(Applet.this);
win.call("updateText", new Object[] { textBox.getText() });
} catch (Exception ex) {
// oops
}
That will update the text each time that chunk of code is called. If you do NOT have access to the applet source, things get trickier. You'd need to set some manner of javascript timeout that constantly reads the value from the applet, but this assumes the applet has such a method that returns the value of the textbox.
See Also: http://java.sun.com/products/plugin/1.3/docs/jsobject.html
Update Modifying the applet is your best shot since that is where any event would be triggered. For example, if you want the HTML TextField to change on every click, the click happens in the applet which would need to be modified to trigger the update, as described above. Without modifying the applet, I see two options. Option #1 uses a timer:
var timer;
var activeTextArea;
$('textarea, input').click(function() {
$(this).dasher();
activeTextArea = this;
updateText();
}
function updateText() {
// Same warnings about textarea vs. input
$(activeTextArea).val($('#appletId')[0].getCurrentEditBoxText());
timer = setTimeout("updateText()", 50);
}
function stopUpdating() {
clearTimeout(timer);
}
This is similar to the code above except clicking on a text area triggers the looping function updateText() which will set the value of the HTML text field to the value of the Applet text field every 50ms. This will potentially introduce a minor delay between click and update, but it'll be small. You can increase the timer frequency, but that will add a performance drain. I don't see where you've 'hidden' the applet, but that same function should call stopUpdating so that we are no longer trying to contact a hidden applet.
Option #2 (not coded)
I would be to try and capture the click in the Applet as it bubbles through the HTML Dom. Then, you could skip the timer and put a click() behavior on the Applet container to do the same update. I'm not sure if such events bubble, though, so not sure if this would work. Even if it did, I'm not sure how compatible it would be across browsers.
Option #3
Third option is to not update the HTML text field on every click. This would simply be a combination of Kyle's and my posts above to set the value of the text field whenever you 'finish' with the applet.

Here's a possible solution. To get the text inside of your Java text box, write a getter method in the Applet to retrieve the text:
public class MyApplet extends JApplet {
// ...
public String getTextBoxText() { return myTextBox.getText(); }
}
In your JQuery code, add the following lines:
var textBoxText = $("#applet-id")[0].getTextBoxText();
//Now do something with the text
I found most of what I posted above here. Hope this helps.

This page explains how to manipulate DOM from a Java applet. To find the input element, simply call the document.getElementById(id) function with id of an id attribute of the text input box.