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  1. Qt
  2. QTBUG-19892

Allow "lazy" aliases to properties of objects created only later

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    Description

      Property bindings are soft, in the sense that they are easily broken
      when the property is assigned a different value.

      Property aliases on the other hand are hard, and will not be broken
      by subsequent assignments. However an alias can only be defined if
      the target object exists at the time the owner of the alias is
      constructed.

      A Binding element can be used to create a hard binding between from
      one property to another. However, for the binding to be two-way the
      same way that aliases are, two Binding elements needs to be defined, one
      binding the two properties in one direction and the other in the other
      direction. This however is impractical when creating generic reusable
      component, as the generic component won't know about its parent's property.

      Thus, support is needed for creating Binding objects that automatically
      create a two-way binding between two properties.

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          duplicates

          Suggestion - Public suggestions QTBUG-68316 QML needs a TwoWay binding like XAML has, to support Model View ViewModel correctly

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed
          relates to

          Task - A task that needs to be done. QTBUG-77622 Avoid accessing properties as strings

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Open

          Task - A task that needs to be done. QTBUG-82713 Avoid QQmlCustomParser in Qt code

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Open

          Suggestion - Public suggestions QTBUG-73892 A way to reference a property from QML

          • P3: Somewhat important - Should be fixed, but doesn't affect the release in any way.
          • Closed
          replaces

          Task - A task that needs to be done. QTBUG-21558 Allow creating two way bindings in QML

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed
          resulted in

          Task - A task that needs to be done. QTBUG-85958 Redesign the Binding element

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Closed
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              qt.team.quick.subscriptions Qt Quick and Widgets Team
              mathiasm Mathias Malmqvist
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              Dates

                Created:
                Updated:
                Resolved:

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