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what qwidget subclass?

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  • U user4592357

    the user will provide a path to the image, and i should go get the image from the path and display it in the widget

    EDIT: i was able to draw using an entry from qrc but what should i do with that user provided icon paths?

    mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by
    #8

    @user4592357

    Ok, sounds like a normal file open dialog
    http://www.codebind.com/cpp-tutorial/qt-tutorial/qt-tutorials-beginners-qfiledialog-getopenfilename-example/

    Then load it via pixmap. Should just work.

    U 1 Reply Last reply
    0
    • mrjjM mrjj

      @user4592357

      Ok, sounds like a normal file open dialog
      http://www.codebind.com/cpp-tutorial/qt-tutorial/qt-tutorials-beginners-qfiledialog-getopenfilename-example/

      Then load it via pixmap. Should just work.

      U Offline
      U Offline
      user4592357
      wrote on last edited by
      #9

      @mrjj

      no i don't need to show a dialog, i just need to go and grab the image located in the user-specified path

      mrjjM 1 Reply Last reply
      0
      • U user4592357

        @mrjj

        no i don't need to show a dialog, i just need to go and grab the image located in the user-specified path

        mrjjM Offline
        mrjjM Offline
        mrjj
        Lifetime Qt Champion
        wrote on last edited by mrjj
        #10

        @user4592357
        Ok, i see no reason it should not work if the paths are fully qualified and
        valid.

        I would test that
        qDebug() << "loading: " pixmap.load(iconPath);
        says true
        also i would try with

        #include <QFileInfo>
        
        bool fileExists(QString path) {
            QFileInfo check_file(path);
            // check if file exists and if yes: Is it really a file and no directory?
            return check_file.exists() && check_file.isFile();
        }
        
        and check iconPath where u try to load the image.
        

        Also where does icon-full-path come from ?
        Is it in the app or do you load from text file ?

        1 Reply Last reply
        1
        • U Offline
          U Offline
          user4592357
          wrote on last edited by
          #11

          thanks. i'll read a text file for that, but why does that matter?

          mrjjM 1 Reply Last reply
          0
          • U user4592357

            thanks. i'll read a text file for that, but why does that matter?

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #12

            @user4592357
            Well if inside the app you must escape

            c:\\xxx\\cyy\\
            

            But that is not valid if from text file so just asking to try to guess reason that is not shown :)

            U 1 Reply Last reply
            1
            • mrjjM mrjj

              @user4592357
              Well if inside the app you must escape

              c:\\xxx\\cyy\\
              

              But that is not valid if from text file so just asking to try to guess reason that is not shown :)

              U Offline
              U Offline
              user4592357
              wrote on last edited by
              #13

              @mrjj

              QFile::exists() gives false when i use a full path for the image (like, C:\Users\user\image.png). but the file sure exists. i've tried using \\ instead of \, also / but not much success. with resource system, however, everything is okay

              mrjjM 1 Reply Last reply
              0
              • U user4592357

                @mrjj

                QFile::exists() gives false when i use a full path for the image (like, C:\Users\user\image.png). but the file sure exists. i've tried using \\ instead of \, also / but not much success. with resource system, however, everything is okay

                mrjjM Offline
                mrjjM Offline
                mrjj
                Lifetime Qt Champion
                wrote on last edited by
                #14

                @user4592357
                if you take one of the paths from the file
                and start paintbrush, select file->open
                and paste the path into the filename area. and then press open.
                will it then open ?

                it sounds really, really wrong if QFile::exists() says false.

                U 1 Reply Last reply
                0
                • mrjjM mrjj

                  @user4592357
                  if you take one of the paths from the file
                  and start paintbrush, select file->open
                  and paste the path into the filename area. and then press open.
                  will it then open ?

                  it sounds really, really wrong if QFile::exists() says false.

                  U Offline
                  U Offline
                  user4592357
                  wrote on last edited by
                  #15

                  @mrjj

                  yes it opens.

                  this is weird, really.
                  this works:

                  QFileInfo file("C:\Users\user\image.png");
                  setIcon(file.filePath());
                  

                  but when i get the SAME line from a file and set the icon to it... it doesn't work

                  mrjjM 1 Reply Last reply
                  0
                  • U user4592357

                    @mrjj

                    yes it opens.

                    this is weird, really.
                    this works:

                    QFileInfo file("C:\Users\user\image.png");
                    setIcon(file.filePath());
                    

                    but when i get the SAME line from a file and set the icon to it... it doesn't work

                    mrjjM Offline
                    mrjjM Offline
                    mrjj
                    Lifetime Qt Champion
                    wrote on last edited by
                    #16

                    Hi
                    Did you try to qDebug() << file.filePath();
                    to see if anything still 100% like the one in file?

                    U 1 Reply Last reply
                    1
                    • mrjjM mrjj

                      Hi
                      Did you try to qDebug() << file.filePath();
                      to see if anything still 100% like the one in file?

                      U Offline
                      U Offline
                      user4592357
                      wrote on last edited by
                      #17

                      @mrjj

                      yes they're the same, actually i've copied them

                      mrjjM 1 Reply Last reply
                      0
                      • U user4592357

                        @mrjj

                        yes they're the same, actually i've copied them

                        mrjjM Offline
                        mrjjM Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on last edited by mrjj
                        #18

                        @user4592357
                        Really cannot guess then.
                        If path in text file truely are valid syntax, it should just work.
                        and you are 100% sure you escape it ?
                        ( which is needed when inside the code, but from text file)

                        setIcon("C:\\Users\\user\\image.png");
                        
                        
                        U 1 Reply Last reply
                        0
                        • mrjjM mrjj

                          @user4592357
                          Really cannot guess then.
                          If path in text file truely are valid syntax, it should just work.
                          and you are 100% sure you escape it ?
                          ( which is needed when inside the code, but from text file)

                          setIcon("C:\\Users\\user\\image.png");
                          
                          
                          U Offline
                          U Offline
                          user4592357
                          wrote on last edited by
                          #19

                          @mrjj

                          yes i've tried everything

                          okay, thanks anyways

                          mrjjM 1 Reply Last reply
                          0
                          • U user4592357

                            @mrjj

                            yes i've tried everything

                            okay, thanks anyways

                            mrjjM Offline
                            mrjjM Offline
                            mrjj
                            Lifetime Qt Champion
                            wrote on last edited by
                            #20

                            @user4592357
                            I have done it many times so I do
                            wonder what you do that is
                            different or if it really just is a path issue.

                            U 1 Reply Last reply
                            0
                            • mrjjM mrjj

                              @user4592357
                              I have done it many times so I do
                              wonder what you do that is
                              different or if it really just is a path issue.

                              U Offline
                              U Offline
                              user4592357
                              wrote on last edited by user4592357
                              #21

                              @mrjj

                              it's really just a path

                              i even tried to QDir::toNativeSeparators(). nothing works

                              1 Reply Last reply
                              0
                              • SGaistS Offline
                                SGaistS Offline
                                SGaist
                                Lifetime Qt Champion
                                wrote on last edited by
                                #22

                                Hi,

                                Since you are using Qt, why not use the Unix notation ? Qt handles the conversion when it calls the related platform specific functions.

                                So it should be C:/Users/user/image.png

                                Interested in AI ? www.idiap.ch
                                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                U 1 Reply Last reply
                                0
                                • SGaistS SGaist

                                  Hi,

                                  Since you are using Qt, why not use the Unix notation ? Qt handles the conversion when it calls the related platform specific functions.

                                  So it should be C:/Users/user/image.png

                                  U Offline
                                  U Offline
                                  user4592357
                                  wrote on last edited by
                                  #23

                                  @SGaist

                                  i've tried that too, it doesn't work

                                  1 Reply Last reply
                                  0
                                  • SGaistS Offline
                                    SGaistS Offline
                                    SGaist
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #24

                                    Does that file have any permission issues ?
                                    Are you 100% sure that it's there ?
                                    Are you loading it from your own user account ?
                                    Any special char in the path ? i.e is user really the account name ?

                                    Interested in AI ? www.idiap.ch
                                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                    1 Reply Last reply
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