Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. Debugging breakpoints that occur while QComboBox popup is open.

Debugging breakpoints that occur while QComboBox popup is open.

Scheduled Pinned Locked Moved Unsolved General and Desktop
6 Posts 4 Posters 823 Views
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • presstabP Offline
    presstabP Offline
    presstab
    wrote on last edited by
    #1

    This is an issue that has plagued me for a while. If I am using the debugger and I hit a breakpoint while a combobox popup is open, it essentially freezes all input of my desktop. This probably has something to do with how the popup listens in modal mode?

    I have this happen on multiple Linux Mint based machines, and am not sure it if it happens on Windows or Mac. My only solution so far has been to use ctrl+alt+f1 to go into a virtual console where I kill the application's process.

    Does anyone else experience this and have a better solution? This makes certain things unable to be debugged for me.

    aha_1980A JonBJ 2 Replies Last reply
    0
    • presstabP presstab

      This is an issue that has plagued me for a while. If I am using the debugger and I hit a breakpoint while a combobox popup is open, it essentially freezes all input of my desktop. This probably has something to do with how the popup listens in modal mode?

      I have this happen on multiple Linux Mint based machines, and am not sure it if it happens on Windows or Mac. My only solution so far has been to use ctrl+alt+f1 to go into a virtual console where I kill the application's process.

      Does anyone else experience this and have a better solution? This makes certain things unable to be debugged for me.

      aha_1980A Offline
      aha_1980A Offline
      aha_1980
      Lifetime Qt Champion
      wrote on last edited by
      #2

      Hi @presstab ,

      no, I've never heard or seen this.

      Which Qt and Creator version?

      Does it happen with a minimal example too?

      Regards

      Qt has to stay free or it will die.

      presstabP 1 Reply Last reply
      0
      • Christian EhrlicherC Offline
        Christian EhrlicherC Offline
        Christian Ehrlicher
        Lifetime Qt Champion
        wrote on last edited by
        #3

        And why do you set breakpoints into this code? :)

        Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
        Visit the Qt Academy at https://academy.qt.io/catalog

        presstabP 1 Reply Last reply
        0
        • presstabP presstab

          This is an issue that has plagued me for a while. If I am using the debugger and I hit a breakpoint while a combobox popup is open, it essentially freezes all input of my desktop. This probably has something to do with how the popup listens in modal mode?

          I have this happen on multiple Linux Mint based machines, and am not sure it if it happens on Windows or Mac. My only solution so far has been to use ctrl+alt+f1 to go into a virtual console where I kill the application's process.

          Does anyone else experience this and have a better solution? This makes certain things unable to be debugged for me.

          JonBJ Offline
          JonBJ Offline
          JonB
          wrote on last edited by JonB
          #4

          @presstab
          Yes, I absolutely have always experienced this. However, it is not (just) a Qt issue, it happens e.g. just from debugging a native Windows combobox. It's to do with the way the dropdown works, and you'll see others questions about this behaviour elsewhere on the web. Depressingly, it also happens under Linux, where you would really hope it would not....

          I have always had to completely reboot the host machine when this happens. I didn't know about ctrl+alt+f1, I will try to remember that next time, and see if it works from my Linux VM under Windows.

          Solution? Assuming your debugger supports it, do not place break points in combobox code, make them trace points. Or manage without them at all. Nice? No. Preferable to getting stuck and rebooting? Yes!

          1 Reply Last reply
          1
          • Christian EhrlicherC Christian Ehrlicher

            And why do you set breakpoints into this code? :)

            presstabP Offline
            presstabP Offline
            presstab
            wrote on last edited by
            #5

            @Christian-Ehrlicher said in Debugging breakpoints that occur while QComboBox popup is open.:

            And why do you set breakpoints into this code? :)

            Multithreaded application with breakpoints in a different thread. Can cause this situation if you happen to have a combobox open while the other thread hits a breakpoint. Also happens if you have signals connected to the combobox that can be triggered before the popup closes. There are really a lot of scenarios that this can happen, while still having full separation of model and view.

            1 Reply Last reply
            1
            • aha_1980A aha_1980

              Hi @presstab ,

              no, I've never heard or seen this.

              Which Qt and Creator version?

              Does it happen with a minimal example too?

              Regards

              presstabP Offline
              presstabP Offline
              presstab
              wrote on last edited by
              #6

              @aha_1980 said in Debugging breakpoints that occur while QComboBox popup is open.:

              Hi @presstab ,

              no, I've never heard or seen this.

              Which Qt and Creator version?

              Does it happen with a minimal example too?

              Regards

              I am currently running Qt 5.12.6 with gcc 64 bit for Qt and QtCreator 4.8.1. I will try a minimalist example an try to confirm that it is an issue there as well.

              1 Reply Last reply
              0

              • Login

              • Login or register to search.
              • First post
                Last post
              0
              • Categories
              • Recent
              • Tags
              • Popular
              • Users
              • Groups
              • Search
              • Get Qt Extensions
              • Unsolved