[Solved] Animation of cursor on touch

McLion

Hi

I have Qt 4.6.3 on eLinux and I am using a PCAP touch that works in parallel to the mouse also using events (Touch Handlers=mouse1 js0 event1 evbug, Mouse Handlers=mouse0 event0 evbug).

I now need to have some animation like a "ring" or something that shows up when a touch event has occurred. I mean, not on a simple touch but on the release that launches the touch function like the button click (event type sequence: 2 5 3).

Is there something alike "ready to use" in Qt or how would I have to implement something like this?

Thanks
McL

SGaist

Hi,

Do you mean change the mouse cursor and show a spinning wheel ?

McLion

Yup, kind of. Showing a spinning wheel for a second or so as a visual feedback to the user that he just clicked an element.

McLion

To start off I tried to change the cursor, though it's only B/W and not animated.

QPixmap TouchEventCursorPixmap(":/TouchEventPNG32");
QCursor TouchEventCursor(TouchEventCursorPixmap, -1, -1);
QApplication::setOverrideCursor(TouchEventCursor);

If I am correct that should change my cursor until I call it off with restoreOverrideCursor().
However, nothing happens and no error on console is output.

What am I doing wrong?

SGaist

Did you check that the pixmap is valid ?

McLion

Thanks for answering. Yes, it is. While playing around I had a too large pixmap. It then did throw an error on the console.
Just found: To make it run I had to place a
QApplication::processEvents();
after the setOverrideCursor. This is probably only needed because I placed it in the MainWindow constructor for testing purpose. I will move it to the notify reimplementation where I catch the mouse and keyboard events and then would probably not need it.

Is there a way to have at least a gray scaled or even colored cursor, maybe bigger than the current maximum of 64x64?

If not, I'll probably have to implement a workaround like showing a graphic for a short time at the location of the touch/click event.
Would that support an animated gif, with transparency?
Do you have a better suggestion?

McLion

Got stuck :-|
I seem not to be able to call a function in my class
class QTGUI_MainWindow : public QMainWindow
from the reimplementation of the notify event:

class MyApplication : public QApplication
{
  public:
    MyApplication(int &argc, char **argv ) : QApplication(argc, argv)
    {
    }
    virtual bool notify ( QObject *receiver, QEvent *event )
       switch( event->type() )
      {
....

There's something I just don't get with these classes in C++ - still used to years of ANSI C.
Can somebody give me a hint how I can solve this?
Tanks a lot.

SGaist

Do you mean your notify implementation doesn't get called ?

McLion

Nope, it's called and working perfectly.
I can perfectly manipulate the cursor with these lines from the notifier:

QPixmap TouchEventCursorPixmap(":/Ring3");
QCursor TouchEventCursor(TouchEventCursorPixmap, -1, -1);
QApplication::setOverrideCursor(QCursor(TouchEventCursor));

Because the problem I got stuck with is actually something different than the main topic of this thread I opened a new one for this here

What is remaining open in this thread is the following:
Is there a way to have at least a gray scaled or even colored cursor, maybe bigger than the current maximum of 64x64?
If not, I'll probably have to implement a workaround like showing a graphic for a short time at the location of the touch/click event.
Would that support an animated gif, with transparency?
Do you have a better suggestion?

SGaist

I don't think it is, however if you need that big a feedback, you should maybe avoid trying to do it on the cursor and have something more general like a spinner in a corner

McLion

Couldn't find anything either.
For now, I leave it with the cursor solution. And I'll try to let a graphic pop up at the cursor location instead of changing the cursor as an option.

Thanks anyway.

McLion

Need to dig up this old thread ...

I (customer) would like to have graphic shown instead of the simple over-ridden cursor.
I am thinking of a png with transparency or even of an animated gif.

What is the best approach to have a small graphic shown very quickly (load fast)?

Something like this maybe:

QGraphicsScene scene;
QGraphicsView view(&scene);
QGraphicsPixmapItem item(QPixmap("c:\\test.png"));
scene.addItem(&item);
view.show();

I'd load the graphic at boot and later only show and hide at the relevant position.
Or is there a faster or better way?

SGaist

At a fixed position ?

McLion

Nope, varying with current touch position.
Couldn't get to display that graphic, and not frameless with the Scene. Tried with a QLabel instead .. again to no avail.

Ended up in adding a Label in the Designer and set it transparent in Designer and load the png in Designer. From code, I am now only updating the position and show and hide.
This now works as expected for a static image. I wonder if this also works with an animated GIF ... will see.

Thanks anyway

SGaist

IIRC, you can use QMovie for gifs

McLion

I'll try that.
Thanks