Qt Quick Demo - Tweet Search

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 import QtQuick 2.0

 Item {
     id: container
     property int animDuration: 300
     property Item front: Item {}
     property Item back: Item {}
     property real factor: 0.1 // amount the edges fold in for the 3D effect
     property alias delta: effect.delta
     property Item cur: frontShown ? front : back
     property Item noncur: frontShown ? back : front

     function swap() {
         var tmp = front;
         front = back;
         back = tmp;
         resync();
     }

     width: cur.width
     height: cur.height
     onFrontChanged: resync();
     onBackChanged: resync();

     function resync() {//TODO: Are the items ever actually visible?
         back.parent = container;
         front.parent = container;
         frontShown ? back.visible = false : front.visible = false;
     }

     property bool frontShown: true

     onFrontShownChanged: {
         back.visible = !frontShown
         front.visible = frontShown
     }

     function flipUp(start) {
         effect.visible = true;
         effect.sourceA = effect.source1
         effect.sourceB = effect.source2
         if (start == undefined)
             start = 1.0;
         deltaAnim.from = start;
         deltaAnim.to = 0.0
         dAnim.start();
         frontShown = false;
     }

     function flipDown(start) {
         effect.visible = true;
         effect.sourceA = effect.source1
         effect.sourceB = effect.source2
         if (start == undefined)
             start = 0.0;
         deltaAnim.from = start;
         deltaAnim.to = 1.0
         dAnim.start();
         frontShown = true;
     }

     ShaderEffect {
         id: effect
         width: cur.width
         height: cur.height
         property real factor: container.factor * width
         property real delta: 1.0

         mesh: GridMesh { resolution: Qt.size(8,2) }

         SequentialAnimation on delta {
             id: dAnim
             running: false
             NumberAnimation {
             id: deltaAnim
             duration: animDuration//expose anim
             }
         }

         property variant sourceA: source1
         property variant sourceB: source1
         property variant source1: ShaderEffectSource {
             sourceItem: front
             hideSource: effect.visible
         }

         property variant source2: ShaderEffectSource {
             sourceItem: back
             hideSource: effect.visible
         }

         fragmentShader: "
             uniform lowp float qt_Opacity;
             uniform sampler2D sourceA;
             uniform sampler2D sourceB;
             uniform highp float delta;
             varying highp vec2 qt_TexCoord0;
             void main() {
                 highp vec4 tex = vec4(qt_TexCoord0.x, qt_TexCoord0.y * 2.0, qt_TexCoord0.x, (qt_TexCoord0.y-0.5) * 2.0);
                 highp float shade = clamp(delta*2.0, 0.5, 1.0);
                 highp vec4 col;
                 if (qt_TexCoord0.y < 0.5) {
                     col = texture2D(sourceA, tex.xy) * (shade);
                 } else {
                     col = texture2D(sourceB, tex.zw) * (1.5 - shade);
                     col.w = 1.0;
                 }
                 gl_FragColor = col * qt_Opacity;
             }
         "
         property real h: height
         vertexShader: "
         uniform highp float delta;
         uniform highp float factor;
         uniform highp float h;
         uniform highp mat4 qt_Matrix;
         attribute highp vec4 qt_Vertex;
         attribute highp vec2 qt_MultiTexCoord0;
         varying highp vec2 qt_TexCoord0;
         void main() {
             highp vec4 pos = qt_Vertex;
             if (qt_MultiTexCoord0.y == 0.0)
                 pos.x += factor * (1. - delta) * (qt_MultiTexCoord0.x * -2.0 + 1.0);
             else if (qt_MultiTexCoord0.y == 1.0)
                 pos.x += factor * (delta) * (qt_MultiTexCoord0.x * -2.0 + 1.0);
             else
                 pos.y = delta * h;
             gl_Position = qt_Matrix * pos;
             qt_TexCoord0 = qt_MultiTexCoord0;
         }"

     }
 }