GAMBAS BOOK 3.18.4

The IconView component (gb.qt4) implements a control that can display labeled icons. IconView elements are indexed by a key. The component has an internal cursor for accessing its elements. Use the MoveFirst, MoveNext, MovePrevious, MoveBack or MoveTo methods to move the internal cursor and the Item property to display the current element.

Figure 17.6.1: IconView in the Project Explorer

The Project Explorer in the examples of Gambas under the heading Miscellaneous uses an IconView to display the directory structure.

The following 2 tables describe selected properties and methods of an IconView:

Table 17.6.1.1: Selected properties of the component IconView

You can assign a self-defined context menu to an IconView, which you call by clicking with the right mouse button (RMT).

The alignment of the displayed text and the icon can take the values Arrange.vertical (text under the icon and vertical display of the icon) or Arrange.horizontal (text next to the icon and horizontal display of the icon).

Methods of an IconView:

Special events of the IconView component can be found here:

Table 17.6.2.1: Overview of events of an IconView

You can use the IconView.sorted property to display the elements in an IconView sorted by the displayed text. The property IconView.Compare and the event IconView_Compare(Key As String, OtherKey As String) also enable you to sort by user-defined criteria. Use the Compare property to display the result of the comparison of a Compare event. The return value of the comparison is valid:

• 0 means that the two elements are equal.
• 1 means that the first element is after the second.
• -1 means that the first element is before the second.

Figure 17.6.3.1: IconView with three elements

The order of the display at program start is determined by the order in which the IconView is filled → Figure 17.6.3.1.

Figure 17.6.3.2: IconView with sorted elements

After sorting with the sort criterion Image.width ∗ Image.height the display has changed → Figure 17.6.3.2. The source text is fully specified:

' Gambas class file
 
Public Sub Form_Open()
  Dim aPaths As String[] = ["icon:/48/book", "icon:/64/calendar", "icon:/32/play"]
  Dim sPath As String
 
  FMain.Center 
  FMain.Resizable = False 
' Als Key wird der Pfad zum Bild gewählt.
  For Each sPath In aPaths
    ivwIcons.Add(sPath, File.BaseName(sPath), Picture[sPath]) ' Füllen der IconView
  Next ' sPath  
End ' Form_Open()
 
Public Sub ivwIcons_Compare(Key As String, OtherKey As String)
  Dim iSize, iOtherSize As Integer
' Sortier-Kriterium: Bild.Breite * Bild.Höhe
  With ivwIcons[Key].Picture
    iSize = .W * .H
  End With
  With ivwIcons[OtherKey].Picture
    iOtherSize = .W * .H
  End With
  ivwIcons.Compare = IIf(iSize = iOtherSize, 0, IIf(iSize > iOtherSize, 1, -1))
  ' Alternative:
  ' ivwIcons.Compare = Sgn(iSize - iOtherSize)
End
 
Public Sub btnSort_Click()
  ' Nach dem Setzen von ivwIcons.Sorted auf True wird das IconView im Hintergrund
  ' eine Reihe von Compare-Events auslösen, um die Liste sortieren zu lassen.
  ' Wird ivwIcons.Sorted auf False gesetzt, dann wird nicht weiter sortiert.
 
  ivwIcons.Sorted = Not ivwIcons.Sorted  
  If ivwIcons.Sorted Then
     btnSort.Text = ("Icon sind sortiert.")
     btnSort.Enabled = False
  Endif ' ivwIcons.Sorted = True ?  
End ' btnSort_Click()

If you set the IconView.editable property to True, you can set a selected element to edit mode with F2, change the text and exit edit mode with Enter. The changed text is copied:

Figure 17.6.4.1: IconView - Rename elements

The extract from the source code allows the edit mode for an icon view with saving of the old text of the renamed icon:

Private $sLastIconName As String
 
Public Sub Form_Open()
  FMain.Center
  FMain.Resizable = True
  ...
  IconView.Editable = True 
End ' Form_Open()
 
Public Sub IconView_Rename()
  Message.Info("Das Icon '" & $sLastIconName & "' wurde umbenannt in " & "'" & \\
                IconView.Current.Text & "'")
End ' IconView_Rename()
 
Public Sub IconView_Select()
  $sLastIconName = IconView.Current.Text
End ' IconView_Select()