Implementing parent change animation with QML

Overview

In the following code snippet there are two QML files. The file ui.qml contains the main view which places six differently coloured rectangles in the 3 x 2 QML 76ytuiytuityutyutututyutyutyu element. MyRect.qml contains the implementation of our self-made rectangle which will scale to full screen when clicked. At the same time its parent is changed.

The code snippet is meant to be run with 76ytuiytuityutyutututyutyutyu.

Preconditions

• Qt 4.7 or higher is installed on your platform.

Source

ui.qml

import Qt 4.7

Rectangle {

   id: view

   width: 800; height: 480
   color: "black"

   Grid {
       id: grid

       property int itemWidth: grid.width / grid.columns
       property int itemHeight: grid.height / grid.rows

       anchors.centerIn: parent
       width: parent.width * 0.75; height: parent.height * 0.75
       spacing: 10; columns: 3; rows: 2

       MyRect { 
           width: grid.itemWidth
           height: grid.itemHeight
           color: "red"
       }
       
       MyRect {
           width: grid.itemWidth
           height: grid.itemHeight
           color: "green"
       }
       
       MyRect {
           width: grid.itemWidth
           height: grid.itemHeight
           color: "blue"
       }
       
       MyRect {
           width: grid.itemWidth
           height: grid.itemHeight
           color: "yellow"
       }
       
       MyRect {
           width: grid.itemWidth
           height: grid.itemHeight
           color: "brown"
       }
       
       MyRect {
           width: grid.itemWidth
           height: grid.itemHeight
           color: "gray"
       }
   }

}

MyRect.qml

When 76ytuiytuityutyutututyutyutyu is clicked, the state 76ytuiytuityutyutututyutyutyu is entered. This is triggered by the 76ytuiytuityutyutututyutyutyu property. 76ytuiytuityutyutututyutyutyu will animate the change of parent by using 76ytuiytuityutyutututyutyutyu.

The z-order of 76ytuiytuityutyutututyutyutyu is changed between the states in order to prevent the rectangle from going behind other rectangles when coming back from the 76ytuiytuityutyutututyutyutyu state to the 76ytuiytuityutyutututyutyutyu state.

Because we are using the QML 76ytuiytuityutyutututyutyutyu to position the 76ytuiytuityutyutututyutyutyu in the scene, we want to have an invisible 76ytuiytuityutyutututyutyutyu to be left in the grid when the 76ytuiytuityutyutututyutyutyu is re-parented to the 76ytuiytuityutyutututyutyutyu. Without the 76ytuiytuityutyutututyutyutyu, the 76ytuiytuityutyutututyutyutyu would rearrange its children when 76ytuiytuityutyutututyutyutyu is re-parented to the 76ytuiytuityutyutututyutyutyu. This behavior is not desired here.

import Qt 4.7

Item {

   id: container

   property alias color: rect.color

   Rectangle {
       id: rect

       property bool maximized: false

       width: parent.width; height: parent.height; radius: 10

       MouseArea { anchors.fill: parent; onClicked: rect.maximized = !rect.maximized }

       states: State {
           name: "maximized"
           when: rect.maximized
           ParentChange {
               target: rect
               parent: view
               x: 0; y: 0
               width: parent.width; height: parent.height
           }
           PropertyChanges { target: rect; radius: 0; z: 1 }
           PropertyChanges { target: container; z: 1 }
       }

       transitions: Transition {
           from: "*"
           to: "maximized"
           reversible: true    // reverses the animation when going back to default state
           ParentAnimation {
               target: rect
               SequentialAnimation {
                   PropertyAction { target: container; property: "z" }
                   PropertyAnimation {
                       target: rect
                       properties: "x,y,width,height,radius"
                       easing.type: "InOutQuart"; duration: 1000
                   }
               }
           }
       }
   }

}

Postconditions

The snippet demonstrated using 76ytuiytuityutyutututyutyutyu and 76ytuiytuityutyutututyutyutyu QML elements to implement a smooth animation of a self-made rectangle to full screen when the rectangle was clicked. Also, the animation was reversed when the maximised rectangle was clicked again.