[SOLVED] How to make a callback function inside a user define class ?

[zheng.guan]

I want to setcallback to a WidgetLabel in a user defined class , but the error that can not find function  shows . I have a look at the widget demo "sprite_02", i think waht i do is the same as it. So, what should i do to solve this ?

 

Thanks

[christian.wolf2]

HI,

 

are you using the game framework? If so, for that you have to modify the callback a little bit. Here is the code I used for all types of widget functions:

Game _game = curLevel.getGame();        //curLevel is a reference to my actual level

	string prefix;

	if (_game != NULL)
		prefix = _game.getLogicNamespaceName();
	else
		log.message("No Game defined!");

        WidgetButton newButton = new WidgetButton(ui,"Simple Button");
	newButton.setCallback(GUI_CLICKED,prefix + "::YourCustomClass::RedirectYourFunction",this);

Be careful that you can only have access to public function. I always used redirect-function to get access to private functions. For the above exsample you have to use:

RedirectYourFunction(YourCustomClass yourclass){yourclass.YourFunction;};

YourFunction()
{
    // do whatever you want
}

One last hint: If you are using the game framework, keep in mind to free the callback-function before destroying the class. Simply use "NULL" as callback-function name to avoid crashing unigine.

[zheng.guan]

HI,

 

are you using the game framework? If so, for that you have to modify the callback a little bit. Here is the code I used for all types of widget functions:

Game _game = curLevel.getGame();        //curLevel is a reference to my actual level

	string prefix;

	if (_game != NULL)
		prefix = _game.getLogicNamespaceName();
	else
		log.message("No Game defined!");

        WidgetButton newButton = new WidgetButton(ui,"Simple Button");
	newButton.setCallback(GUI_CLICKED,prefix + "::YourCustomClass::RedirectYourFunction",this);

Be careful that you can only have access to public function. I always used redirect-function to get access to private functions. For the above exsample you have to use:

RedirectYourFunction(YourCustomClass yourclass){yourclass.YourFunction;};

YourFunction()
{
    // do whatever you want
}

One last hint: If you are using the game framework, keep in mind to free the callback-function before destroying the class. Simply use "NULL" as callback-function name to avoid crashing unigine.

thanks, it worked ! :D

[zheng.guan]

thanks, it worked ! :D

Sorry, it crashed ! I havn't understand that "use NULL as callback-function name" . Can you show a example with code ?

Thank very much !

[christian.wolf2]

Can you show a example with code ?

 

Sure. The problem is, that a callback-function still exist after deleting a button e.g. and you don't get a hint about existing "ghost"-callbacks. So I used the following code, to scan all childs of an widget and delete the callback-function.

void DeleteChildCallbacks(Widget parentWidget)
	{
		if (parentWidget.getType() == WIDGET_BUTTON)
			parentWidget.setCallback(GUI_CLICKED,NULL);

		forloop(int i = 0; parentWidget.getNumChilds();1)
		{
			Widget childWidget = parentWidget.getChild(i);
			//log.message("Widget %s have %d childs, that will be deleted",childWidget.getTypeName(),childWidget.getNumChilds());
			if (childWidget.getNumChilds() > 0)
				DeleteChildCallbacks(parentWidget.getChild(i));
			else			
				if (childWidget.getType() == WIDGET_BUTTON)
					childWidget.setCallback(GUI_CLICKED,NULL);    //that's the interesting line for you
		}
	}

Best regards,

Christian