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. QScrollArea not expanding when QPixmap is loaded
Forum Updated to NodeBB v4.3 + New Features

QScrollArea not expanding when QPixmap is loaded

Scheduled Pinned Locked Moved Unsolved General and Desktop
qscrollareaqpixmapqlabel
3 Posts 3 Posters 822 Views 3 Watching
  • 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.
  • C Offline
    C Offline
    Conical
    wrote on last edited by Conical
    #1

    Hi all,

    I'm working on a program that requires the user to load an image. I am using a QPixmap inside of a QLabel for the image, and that QLabel is inside a QScrollArea. When the program first starts, the label is empty, and thus the scroll area doesn't have anywhere to scroll (as intended). However, when I load an image that requires scrolling, the scroll bars do not change, and I can only see the top corner of the image.

    Currently, this is the code that sets the image in the QLabel (the image paths are stored in a list):

    void MainWindow::on_imageList_doubleClicked(const QModelIndex &index)
    {
        QPixmap image(imageModel->itemData(index)[0].toString());
        ui->imagePanel->setPixmap(image);
    }
    

    As I said earlier, the QLabel (imagePanel) is inside the scroll area, so I am confused as to why the scroll bars do not expand to accommodate a large image.

    Any helps would be much appreciated.

    Edit: I admit that my explanation is a little confusing, so here's a screenshot showing what I mean. The picture is supposed to be scrollable so you can view the entire cat, but only a small part of the picture can be seen and the scroll bars do not work.
    Screenshot_2020-03-24_15-39-17.png
    I can somewhat get around the issue by setting the QLabel scaledContents to true, but it's not ideal as the height/width ratio is not maintained.

    raven-worxR 1 Reply Last reply
    0
    • C Conical

      Hi all,

      I'm working on a program that requires the user to load an image. I am using a QPixmap inside of a QLabel for the image, and that QLabel is inside a QScrollArea. When the program first starts, the label is empty, and thus the scroll area doesn't have anywhere to scroll (as intended). However, when I load an image that requires scrolling, the scroll bars do not change, and I can only see the top corner of the image.

      Currently, this is the code that sets the image in the QLabel (the image paths are stored in a list):

      void MainWindow::on_imageList_doubleClicked(const QModelIndex &index)
      {
          QPixmap image(imageModel->itemData(index)[0].toString());
          ui->imagePanel->setPixmap(image);
      }
      

      As I said earlier, the QLabel (imagePanel) is inside the scroll area, so I am confused as to why the scroll bars do not expand to accommodate a large image.

      Any helps would be much appreciated.

      Edit: I admit that my explanation is a little confusing, so here's a screenshot showing what I mean. The picture is supposed to be scrollable so you can view the entire cat, but only a small part of the picture can be seen and the scroll bars do not work.
      Screenshot_2020-03-24_15-39-17.png
      I can somewhat get around the issue by setting the QLabel scaledContents to true, but it's not ideal as the height/width ratio is not maintained.

      raven-worxR Offline
      raven-worxR Offline
      raven-worx
      Moderators
      wrote on last edited by
      #2

      @Conical
      you need to resize the QLabel in the scrollarea to the size of the pixmap

      --- SUPPORT REQUESTS VIA CHAT WILL BE IGNORED ---
      If you have a question please use the forum so others can benefit from the solution in the future

      1 Reply Last reply
      0
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #3

        Hi,

        How did you set the QLabel on your QScrollArea ?

        If you put it in a layout on the scroll area then that's wrong.

        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
        0

        • Login

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