Add .SetIcon() to custom dialogs

dialog/base.go

@@ -140,6 +140,11 @@ func (d *dialog) setButtons(buttons fyne.CanvasObject) {
 	d.win.Refresh()
 }
 
+func (d *dialog) setIcon(icon fyne.Resource) {
+	d.win.Content.(*fyne.Container).Objects[0] = &canvas.Image{Resource: icon}
+	d.win.Refresh()
+}
+
 // The method .create() needs to be called before the dialog can be shown.
 func newDialog(title, message string, icon fyne.Resource, callback func(bool), parent fyne.Window) *dialog {
 	d := &dialog{content: newCenterWrappedLabel(message), title: title, icon: icon, parent: parent}

dialog/custom.go

@@ -55,6 +55,14 @@ func (d *CustomDialog) SetButtons(buttons []fyne.CanvasObject) {
 	d.setButtons(container.NewGridWithRows(1, buttons...))
 }
 
+// SetIcon sets an icon to be shown on the right of the dialog, like the NewInformation dialog.
+// Passing a nil resource will remove the icon from the dialog.
+//
+// Since: 2.6
+func (d *CustomDialog) SetIcon(icon fyne.Resource) {
+	d.setIcon(icon)
+}
+
 // ShowCustomWithoutButtons shows a dialog, without buttons, over the specified application
 // using custom content.
 // The MinSize() of the CanvasObject passed will be used to set the size of the window.