SCROLLBAR not always giving WM_NOTIFICATION_RELEASED

    This site uses cookies. By continuing to browse this site, you are agreeing to our Cookie Policy.

    • SCROLLBAR not always giving WM_NOTIFICATION_RELEASED

      Hi,
      I'm using a scrollbar to navigate in a larger text file. To avoid excessive CPU load when moving the thumb I want to notify only when the thumb is released (WM_NOTIFICATION_RELEASED). Now I noticed that sometimes the thumb is moved but no notification issued. Isn't it a precondition that the widget has to be clicked to change its value and then is released?

      Regards
      Jan
    • Hi,

      I tried to reproduce the behavior you noticed, but the widget always sent a WM_NOTIFY_PARENT message when releasing the press, and also when releasing outside of the scrollbar window.

      Best regards,

      Florian
      Please read the forum rules before posting.

      Keep in mind, this is *not* a support forum.
      Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
      Should you be entitled to support you can contact us via our support system: segger.com/ticket/

      Or you can contact us via e-mail.
    • Hi,

      when the value of the SCROLLBAR changed, the notification code of the WM_NOTIFY_PARENT will be WM_NOTIFICATION_VALUE_CHANGED instead of WM_NOTIFICATION_RELEASED. This is intentional, since its value is what the widget is used for most of the times.

      For your purpose, I would just react on the WM_NOTIFICATION_VALUE_CHANGED code. This would make the most sense for scrolling through a text file. When the value changed, you can update your window accordingly, using the new scroll position.

      Best regards,

      Florian
      Please read the forum rules before posting.

      Keep in mind, this is *not* a support forum.
      Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
      Should you be entitled to support you can contact us via our support system: segger.com/ticket/

      Or you can contact us via e-mail.