Uploaded image for project: 'Qt'
  1. Qt
  2. QTBUG-141114

Qml: Binding on deferred property not reliable

XMLWordPrintable

      Using a Binding on a "deferred property" is not reliable.

      Please see the following example: the background should become blue (for demonstration purposes, actually it should just have some background color without a frame).

      Interestingly, setting the property to null works.

      Motivation for this was to compensate for the behavior change from Qt 6.9.2 to 6.9.3 due to the fix for QTBUG-139715 by adding a frameless property to some TextArea based control.

      import QtQuick
import QtQuick.Controls.Fusion

ApplicationWindow {
  id: root

  width: 640
  height: 480
  visible: true
  title: qsTr("Hello World")

  TextArea {
    id: editor

    anchors {
      fill: parent
      margins: 10
    }

    text: "Foo"

    // works
    // background: Rectangle { implicitWidth: 10; implicitHeight: 10; color: "blue" }

    Binding {
      // does *not* work
      editor.background: Rectangle { implicitWidth: 10; implicitHeight: 10; color: "blue" }

      // works:
      // editor.background: null

      when: true // real application would e.g. bind this to some "frameless" property
    }
  }
}

        1. QTBUG-141114.7z
          1 kB
        No reviews matched the request. Check your Options in the drop-down menu of this sections header.

            qtqmlteam Qt Qml Team User
            njeisecke_qtc Nils Jeisecke
            Votes:
            0 Vote for this issue
            Watchers:
            4 Start watching this issue

              Created:
              Updated:

                There are no open Gerrit changes