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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.

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.

Selenium, Java, waitForCondition

I want to check the following (on ie8):
After clicking on a link, popup window is launched, then I want to check if flash content inside has loaded.
For some reason waitForPopUp does not work, it just keeps waiting and times out but I've solved it this way:
selenium.waitForCondition("selenium.getAllWindowTitles().length > 1;", "30000");
String windowID = selenium.getAllWindowTitles()[1];
selenium.selectWindow(windowID);
Then I want to check if the flash content is there before checking anything on it (webpage is very slow and the popup takes a while to show something)
selenium.waitForCondition("selenium.isElementPresent(\"//*[#id='flashcontent']\");",
"30000");
FlashSelenium flashApp = new FlashSelenium(selenium, "flashClient");
assertTrue ( flashApp.PercentLoaded() == 100 );
I've tried hundreds of ways to do this but none works,
I've also tried to check if a text is present but nothing, always times out even if the webpage is completely loaded.
For some reason everything works OK if I execute step by step in the debugger :S

I gave this a little more thought.
There is no way to test an object if it is truely loaded and the flash app is ready and initialized.
The only true way of letting selenium know the flash object is loaded and ready is for flash to use the ExternalInterface method and call a JavaScript function that will assign a var and then have selenium test that var on a timer.
Example<br/>
// in JavaScript
var isFlashLoaded = false;
function cbIsLoaded( ){
isFlashLoaded = true;
}
// in AS3
var retVal:int = ExternalInterface.call("cbIsLoaded");

selecting pulldown in htmlunit

I am using htmlunit in jython and am having trouble selecting a pull down link. The page I am going to has a table with other ajax links, and I can click on them and move around and it seems okay but I can't seem to figure out how to click on a pulldown menu that allows for more links on the page(this pulldown affects the ajax table so its not redirecting me or anything).
Here's my code:
selectField1 = page.getElementById("pageNumSelection")
options2 = selectField1.getOptions()
theOption3 = options2[4]
This gets the option I want, I verify its right. so I select it:
MoreOnPage = selectField1.setSelectedAttribute(theOption3, True)
and I am stuck here(not sure if selecting it works or not because I don't get any message, but I'm not sure what to do next. How do I refresh the page to see the larger list? When clicking on links all you have to do is find the link and then select linkNameVariable.click() into a variable and it works. but I'm not sure how to refresh a pulldown. when I try to use the webclient to create an xml page based on the the select variable, I still get the old page.
to make it a bit easier, I used htmlunit scripter and got some code that should work but its java and I'm not sure how to port it to jython. Here it is:
try
{
page = webClient.getPage( url );
HtmlSelect selectField1 = (HtmlSelect) page.getElementById("pageNumSelection");
List<HtmlOption> options2 = selectField1.getOptions();
HtmlOption theOption3 = null;
for(HtmlOption option: options2)
{
if(option.getText().equals("100") )
{
theOption3 = option;
break;
}
}
selectField1.setSelectedAttribute(theOption3, true );

Have a look at HtmlForm getSelectedByName
HtmlSelect htmlSelect = form.getSelectByName("stuff[1].type");
HtmlOption htmlOption = htmlSelect.getOption(3);
htmlOption.setSelected(true);

Be sure that WebClient.setJavaScriptEnabled is called. The documentation seems to indicate that it is on by default, but I think this is wrong.
Alternatively, you can use WebDriver, which is a framework that supports both HtmlUnit and Selenium. I personally find the syntax easier to deal with than HtmlUnit.

If I understand correctly, the selection of an option in the select box triggers an AJAX calls which, once finished, modifies some part of the page.
The problem here is that since AJAX is, by definition, asynchronous, you can't really know when the call is finished and when you may inspect the page again to find the new content.
HtmlUnit has a class named NicelyResynchronizingAjaxController, which you can pass an instance of to the WebClient's setAjaxController method. As indicated in the javadoc, using this ajax controller will automatically make the asynchronous calls coming from a direct user interaction synchronous instead of asynchronous. Once the setSelectedAttribute method is called, you'll thus be able to see the changed made to the original page.
The other option is to use WebClient's waitForBackgrounfJavascript method after the selection is done, and inspect he page once the background JavaScript has ended, or the timeout has been reached.

This isn't really an answer to the question because I've not used HtmlUnit much before, but you might want to look at Selenium, and in particular Selenium RC. With Selenium RC you are able to control the interactions with a page displayed in a native browser (Firefox for example). It has developer API's for Java and Python amongst others.
I understand that HtmlUnit uses its own javascript and web browser rendering engine and I'm wondering whether that may be a problem.

In GWT, how to reset the URL when the user hits "Cancel" in the navigation confirmation dialog?

In my GWT application, I want to ask a user confirmation when he navigates out of the current application, i.e. by entering a URL or closing the browser. This is typically done by registering a ClosingHandler and setting the desired dialog message in the onWindowClosing method. This seems to work well.
However, if the user tries to navigate say to http://www.gmail.com (by typing it in the URL bar) and hits Cancel to indicate he doesn't want to navigate, then my app keeps running but the browser's URL bar keeps indicating http://www.gmail.com. This causes a number of problems later in my application and will give the wrong result if the user bookmarks the page.
Is there a way to automatically reset the URL when the user presses Cancel?
Or, alternatively, is there a way to detect the user pressed the Cancel button? If so, is there a way to set the URL without triggering a ValueChangeEvent? (I could add some logic to prevent this, but I'd rather use a built-in mechanism if it exists.)

Not sure if this works but did you try: History.newItem(History.getToken(), false); to reset the URL? It does set the history token without triggering a new history item.

I managed to do this. It looks like GWT DeferredCommand are executed after the confirmation window has been closed. This, combined with Hilbrand's answer above, give me exactly what I want. Here is exactly what I do:
public final void onWindowClosing(Window.ClosingEvent event) {
event.setMessage(onLeaveQuestion);
DeferredCommand.addCommand( new Command() {
public void execute() {
Window.Location.replace(currentLocation);
}
});
}
Where currentLocation is obtained by calling Window.Location.getHref() every time the history token changes.

I solved this by creating a custom PlaceController and replacing the token in the url. Not an ideal solution but it works!
if (warning == null || Window.confirm(warning)) {
where = newPlace;
eventBus.fireEvent(new PlaceChangeEvent(newPlace));
currentToken = History.getToken();
} else {
// update the url when user clicks cancel in confirm popup.
History.replaceItem(currentToken, false);
}