Animate control can not play in a callback function

Question

Hello,
I'v programmed a code:
static int panelHandle;
static int flag = 0;
static int picID;  
int CVICALLBACK ProcAnimate (int panelHandle, int controlID, int event, void *callbackData, int eventData1, int eventData2);
int main (int argc, char *argv[])
    if (InitCVIRTE (0, argv, 0) == 0)
        return -1;    /* out of memory */
    if ((panelHandle = LoadPanel (0, "testanimate.uir", PANEL)) < 0)
        return -1;
    picID = AnimateCtrl_ConvertFromPictRing(panelHandle, PANEL_PICTURERING);
    InstallCtrlCallback(panelHandle, PANEL_PICTURERING, ProcAnimate, NULL);
    DisplayPanel (panelHandle);
    RunUserInterface ();
    DiscardPanel (panelHandle);
    return 0;
int CVICALLBACK ProcAnimate (int panelHandle, int controlID, int event,
                                                 void *callbackData, int eventData1, int eventData2)
    int res ;
    if (event == EVENT_LEFT_DOUBLE_CLICK)
        if (flag == 0)
            res = AnimateCtrl_SetAttribute(panelHandle, picID, ATTR_ANIMATE_FRAME_INTERVAL, 0.4);
            res = AnimateCtrl_SetAttribute (panelHandle, picID, ATTR_ANIMATE_ENABLED, 1);
            flag = 1;
        else
            AnimateCtrl_SetAttribute (panelHandle, picID, ATTR_ANIMATE_ENABLED, 0);    
            flag = 0;
    return 0;
Hope double clicked the picture ring it can play animation. but I found that  the variable res got an error (-45). What is wrong?
David

Answer 1

Attached your project modified and working. The solution is to set control callback in the editori instead of using InstallCtrlCallback (it is basically one of the suggestions I already gave to you: you could have tried it and solution your problem earlier  )
Alternatively, if you want/need to dynamically install the callback, set it before creating the animation control and the system will still be working.
When dealing with custom controls, you must understand that almost all of them use a special callback to accomplish control function. That callback is chained to a control callbak that eventually exists, and must not be modified afterwards, otherwise control behaviour will be affected (cancelled like in your case, you could also get GPFs or other errors for more complex controls). I have it as a general rule for myself: when I need to set some attribute for controls used to generate custom controls, I set it before passing the control to instrument functions.
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Attachments:
testanimate.zip ‏41 KB