import QtQuick 2.0
import QtQuick.Layouts 1.0

Rectangle {
    width: 360
    height: 360

    Loader {
        id: loader

        width: parent.width
        height: (loader.sourceComponent == one ? 30 : 150)
        anchors.centerIn: parent
        sourceComponent: one
    }

    Component {
        id: one

        ColumnLayout {

            RowLayout {
                Layout.fillHeight: true
                Layout.fillWidth: true

                Rectangle {
                    Layout.fillHeight: true
                    Layout.fillWidth: false
                    implicitWidth: height
                    color: "red"
                }
                Rectangle {
                    Layout.fillHeight: true
                    Layout.fillWidth: true
                    color: "blue"
                }
            }
        }
    }

    Component {
        id: two

        Rectangle {
            color: "black"
        }
    }
}