title: How to show "waiting" while files are loaded in a Qt application?
body: <p>I'm selecting and loading some big Dicom files on my program. The whole loading process takes a long time(depends on the number of files, but the whole process can take more than minutes if the files are many). I want show a "waiting symbol" or something like that when the file uploading is going on. I searched for it, but I didn't get anything definite.</p>
  
  <p>My code for the selection and uploading part is as below:</p>
  
  <pre><code>void MainWindow::showTheSelectedList()
  {
      QFileDialog * fileDialog = new QFileDialog(this);
  
      fileDialog-&gt;setFileMode(QFileDialog::ExistingFiles);
      QListView* list = fileDialog-&gt;findChild&lt;QListView*&gt;("listView");
      if(list)
      {
          list-&gt;setSelectionMode(QAbstractItemView::MultiSelection);
      }
      QTreeView* tree = fileDialog-&gt;findChild&lt;QTreeView*&gt;();
      if(tree)
      {
          tree-&gt;setSelectionMode(QAbstractItemView::MultiSelection);
      }
      if(fileDialog-&gt;exec())
      {
          if(fileDialog-&gt;selectedFiles().size()&gt;0)
          {
  
              int listsize=stringList.size();
              for(int i=0;i&lt;listsize;i++)
              {
        //          get the name of the file
          //        check if the file is dicom
            //      upload if the file is dicom
              //    after uploading, get the pixel data of that file
                //  use the pixel data and make a icon out of it
                  //then insert the icon in an a QTablewView
              }
          }
      }
      //show the QtableView
  }
  </code></pre>
  
  <p>Could you please instruct me where and how I can show the waiting sign or symbol while the uploading part is running?</p>
  
  <p>Thanks</p>