Uncaught Type Error

Hello,
I have a web app and in one of its pages i open a web dialog. The web dialog loads an HTMLViewer. The problem is that when i close the Web Dialog sometimes i get the following error (when i move mouse inside the web App) and other times i don’t.

Here is the error:
framework.js:3335 Uncaught TypeError: Cannot read property ‘children’ of null
at textlabel.controlObject (framework.js:3335)
at HTMLDocument.Xojo.input.move (framework.js:1683)
textlabel.controlObject @ framework.js:3335
Xojo.input.move @ framework.js:1683

@Dimitris Rousis - I have a similar infrequent error on a WebPage as I open it to show another WebContainer. I have exception reporting inside the WebPage and WebContainers . This error is not caught in the debugger only reported to the screen.

[quote]Could not execute returned javascript: Cannot read property ‘setValue’ of undefined
Source: document.title = “NY_WEBS_MAIN_MPLD - MAC XFER”;
Xojo.controls[‘pFbtVJ3l’].setEnabled(true);
Xojo.controls[‘pFbtVJ3l’].refresh();
Xojo.controls[‘l7JKxEV5’].setValue(“NY_WEBS_MAIN_MPLD - MAC XFER”);[/quote]

and this one

[quote]Could not execute returned javascript: Cannot read property ‘children’ of null
Source: Xojo.control.destroy(‘qmwAGzgt’);[/quote]

This is part of a large project and every effort I make to reduce this so I can share it eliminates the error.

These errors occur sporadically and almost certainly works after the error occurs. Not certain how to proceed

I found the cause of the errors in my standalone web app - Threads that place information to the user. If you have calculations or anything that is a considerable task and that code block does not place information on the screen then a Thread could be a solution. Otherwise if you are placing information on the screen do not use a Thread.

In a web app you should be using WebThreads. You’ll probably have better luck with that.

@Greg O’Lone - Thats what I used. Using a WebThread the errors would occur quickly and regularly. I moved the code of the WebThread to a WebTimer and the Java errors identified above have not occurred.

@Dimitris Rousis - I have the same problem and I’m not using WebThreads.

Did you find a solution to the problem?

@Jan Knudsen - yes as stated I moved the code to WebTimer and the JAVA errors went away.