qtdeclarative/tests/auto/quick/qquickpositioners/data/implicitGridOneItem.qml

import QtQuick 2.9
import PositionerTest 1.0

ImplicitGrid {
    columns: 2
    rows: 1

    Text {
        text: "Text"
        width: parent.width
    }
}
Positioners: allow distinguishing between implicit/explicit child size In Qt Quick Controls 2, we plan on using positioners to layout an icon next to text in a button, for example. Consider the following example: AbstractButton { id: button text: "Button" contentItem: Row { Text { text: button.text width: parent.width } } background: Rectangle { radius: 5 color: "lightsteelblue" opacity: button.pressed ? 1.0 : 0.8 } } In Qt Quick Controls 2, implicit size propagates "up" from the delegates/building blocks to the control, whereas explicit size propagates "down" from the control to the delegates/building blocks. Providing a reasonable implicit size is important to make controls behave well in layouts, etc., and the internal building blocks must follow the size of the control to retain sensible looks when a control is resized. In the example above, contentItem needs to have a "natural" (implicit) size representing the ideal fit of the content, but it needs to respect the explicitly provided size from the control too. With the current behavior, as the explicit width of the Row is 0, the Text item (via the width binding) sets explicit width to 0, and Row uses that explicit width rather than the implicit width, thus, Row here will have an implicit width of 0, which is not what the control wants. This patch: - Allows subclasses of positioners to set QQuickBasePositionerPrivate::useImplicitSize to true in order to tell positioners to use implicit size rather than explicit size. This is not exposed as public API, as this behavior is typically not something desirable in the positioners themselves. For example, Row { Rectangle { width: 100; height: 100 } } would have an implicit size of 0, as Rectangle has no implicit size. - Adds QQuickImplicitRow and QQuickImplicitGrid, which are private subclasses of their respective positioners that simply set useImplicitSize to true in their constructors. - Exports the wrappers privately so that they can be registered by other modules as QML types. Change-Id: Ie68aabd7fbf6c76375badf6e338f2f238f3fc392 Reviewed-by: J-P Nurmi <jpnurmi@qt.io> Reviewed-by: Robin Burchell <robin.burchell@crimson.no> 2017-02-07 12:54:29 +00:00			`import QtQuick 2.9`
			`import PositionerTest 1.0`

			`ImplicitGrid {`
			`columns: 2`
			`rows: 1`

			`Text {`
			`text: "Text"`
			`width: parent.width`
			`}`
			`}`