Enginio QML Examples - Image Gallery

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 import QtQuick 2.0
 import Enginio 1.0

 import QtQuick.Dialogs 1.0
 import QtQuick.Controls 1.0
 import QtQuick.Layouts 1.0

 /*
  * Enginio image gallery example.
  *
  * Main window contains list of enginioModel on the backend and button for uploading
  * new enginioModel. Image list contains image thumbnail (generated by Enginio
  * backend) and some image metadata. Clicking list items downloads image file
  * and displays it in dialog window. Clicking the red x deletes enginioModel from
  * backend.
  *
  * In the backend enginioModel are represented as objects of type "objects.image". These
  * objects contain a property "file" which is a reference to the actual binary file.
  */

 Item {
     id: main
     width: 460
     height: 640

     BackendHelper{
         id: backendHelper
     }

     property var imagesUrl: new Object
     Rectangle {
         id: root
         anchors.fill: parent
         opacity: 1 - backendHelper.opacity
         color: "#f4f4f4"

         // Enginio client specifies the backend to be used
         EnginioClient {
             id: client
             backendId: backendHelper.backendId
             onError: console.log("Enginio error: " + reply.errorCode + ": " + reply.errorString)
         }

         EnginioModel {
             id: enginioModel
             client: client
             query: { // query for all objects of type "objects.image" and include not null references to files
                 "objectType": "objects.image",
                 "include": {"file": {}},
                 "query" : { "file": { "$ne": null } }
             }
         }

         // Delegate for displaying individual rows of the model
         Component {
             id: imageListDelegate

             BorderImage {
                 height: 120
                 width: parent.width
                 border.top: 4
                 border.bottom: 4
                 source: hitbox.pressed ? "qrc:images/delegate_pressed.png" : "qrc:images/delegate.png"

                 Image {
                     id: shadow
                     anchors.top: parent.bottom
                     width: parent.width
                     visible: !hitbox.pressed
                     source: "qrc:images/shadow.png"
                 }

                 Image {
                     id: image
                     x: 10
                     width: 100
                     height: 100
                     anchors.verticalCenter: parent.verticalCenter
                     opacity: image.status == Image.Ready ? 1 : 0
                     Behavior on opacity { NumberAnimation { duration: 100 } }
                     Component.onCompleted: {
                         if (id in imagesUrl) {
                             image.source = imagesUrl[id]
                         } else {
                             var data = { "id": file.id,
                                 "variant": "thumbnail"}
                             var reply = client.downloadUrl(data)
                             reply.finished.connect(function() {
                                 imagesUrl[id] = reply.data.expiringUrl
                                 if (image && reply.data.expiringUrl) // It may be deleted as it is delegate
                                     image.source = reply.data.expiringUrl
                             })
                         }
                     }
                 }
                 Rectangle {
                     color: "transparent"
                     anchors.fill: image
                     border.color: "#aaa"
                     Rectangle {
                         id: progressBar
                         property real value:  image.progress
                         anchors.bottom: parent.bottom
                         width: image.width * value
                         height: 4
                         color: "#49f"
                         opacity: image.status != Image.Ready ? 1 : 0
                         Behavior on opacity {NumberAnimation {duration: 100}}
                     }
                 }

                 Column {
                     anchors.left: image.right
                     anchors.right: deleteIcon.left
                     anchors.margins: 12
                     y: 10
                     Text {
                         height: 33
                         width: parent.width
                         verticalAlignment: Text.AlignVCenter
                         font.pixelSize: height * 0.5
                         text: name ? name : ""
                         elide: Text.ElideRight
                     }
                     Text {
                         height: 33
                         width: parent.width
                         verticalAlignment: Text.AlignVCenter
                         font.pixelSize: height * 0.5
                         text: sizeStringFromFile(file)
                         elide:Text.ElideRight
                         color: "#555"
                     }
                     Text {
                         height: 33
                         width: parent.width
                         verticalAlignment: Text.AlignVCenter
                         font.pixelSize: height * 0.5
                         text: timeStringFromFile(file)
                         elide:Text.ElideRight
                         color: "#555"
                     }
                 }

                 // Clicking list item opens full size image in separate dialog
                 MouseArea {
                     id: hitbox
                     anchors.fill: parent
                     onClicked: {
                         imageDialog.fileId = file.id;
                         imageDialog.visible = true
                         root.state = "view"
                     }
                 }

                 // Delete button
                 Image {
                     id: deleteIcon
                     anchors.right: parent.right
                     anchors.verticalCenter: parent.verticalCenter
                     anchors.rightMargin: 18
                     source: removeMouseArea.pressed ?"qrc:icons/delete_icon_pressed.png" : "qrc:icons/delete_icon.png"
                     MouseArea {
                         id: removeMouseArea
                         anchors.fill: parent
                         anchors.margins: -10
                         onClicked: enginioModel.remove(index)
                     }
                 }
             }
         }

         // A simple layout:
         // a listview and a line edit with button to add to the list
         Rectangle {
             id: header
             anchors.top: parent.top
             width: parent.width
             height: 70
             color: "white"

             Row {
                 id: logo
                 anchors.centerIn: parent
                 anchors.horizontalCenterOffset: -4
                 spacing: 6
                 Image {
                     source: "qrc:images/enginio.png"
                     width:160 ; height: 60
                     fillMode:Image.PreserveAspectFit
                 }
                 Text {
                     text: "Gallery"
                     anchors.verticalCenter: parent.verticalCenter
                     anchors.verticalCenterOffset: -3
                     font.bold: true
                     font.pixelSize: 46
                     color: "#555"
                 }
             }
             Rectangle {
                 width: parent.width ; height: 1
                 anchors.bottom: parent.bottom
                 color: "#bbb"
             }
         }

         Row {
             id: listLayout

             Behavior on x {NumberAnimation{ duration: 400 ; easing.type: "InOutCubic"}}
             anchors.top: header.bottom
             anchors.bottom: footer.top

             ListView {
                 id: imageListView
                 model: enginioModel // get the data from EnginioModel
                 delegate: imageListDelegate
                 clip: true
                 width: root.width
                 height: parent.height
                 // Animations
                 add: Transition { NumberAnimation { properties: "y"; from: root.height; duration: 250 } }
                 removeDisplaced: Transition { NumberAnimation { properties: "y"; duration: 150 } }
                 remove: Transition { NumberAnimation { property: "opacity"; to: 0; duration: 150 } }
             }

             // Dialog for showing full size image
             Rectangle {
                 id: imageDialog
                 width: root.width
                 height: parent.height
                 property string fileId
                 color: "#333"

                 onFileIdChanged: {
                     image.source = ""
                     // Download the full image, not the thumbnail
                     var data = { "id": fileId }
                     var reply = client.downloadUrl(data)
                     reply.finished.connect(function() {
                         image.source = reply.data.expiringUrl
                     })
                 }
                 Label {
                     id: label
                     text: "Loading ..."
                     font.pixelSize: 28
                     color: "white"
                     anchors.centerIn: parent
                     visible: image.status != Image.Ready
                 }
                 Rectangle {
                     property real value: image.progress
                     anchors.bottom: parent.bottom
                     width: parent.width * value
                     height: 4
                     color: "#49f"
                     Behavior on opacity {NumberAnimation {duration: 200}}
                     opacity: image.status !== Image.Ready ? 1 : 0
                 }
                 Image {
                     id: image
                     anchors.fill: parent
                     anchors.margins: 10
                     smooth: true
                     cache: false
                     fillMode: Image.PreserveAspectFit
                     Behavior on opacity { NumberAnimation { duration: 100 } }
                     opacity: image.status === Image.Ready ? 1 : 0
                 }
                 MouseArea {
                     anchors.fill: parent
                     onClicked: root.state = ""
                 }
             }
         }

         BorderImage {
             id: footer

             width: parent.width
             anchors.bottom: parent.bottom
             source: addMouseArea.pressed ? "qrc:images/delegate_pressed.png" : "qrc:images/delegate.png"
             border.left: 5; border.top: 5
             border.right: 5; border.bottom: 5

             Rectangle {
                 y: -1 ; height: 1
                 width: parent.width
                 color: "#bbb"
             }
             Rectangle {
                 y: 0 ; height: 1
                 width: parent.width
                 color: addMouseArea.pressed ? "transparent" : "white"
             }


             Text {
                 text: "Click to upload..."
                 font.bold: true
                 font.pixelSize: 28
                 color: "#444"
                 anchors.centerIn: parent
             }

             Item {
                 id: addButton
                 width: 40 ; height: 40
                 anchors.margins: 20
                 anchors.right: parent.right
                 anchors.verticalCenter: parent.verticalCenter
                 Image {
                     id: removeIcon
                     source: addMouseArea.pressed ? "qrc:icons/add_icon_pressed.png" : "qrc:icons/add_icon.png"
                     anchors.centerIn: parent
                 }
             }

             MouseArea {
                 id: addMouseArea
                 anchors.fill: parent
                 onClicked: fileDialog.visible = true;
             }
             Rectangle {
                 id: progressBar
                 property real value:0
                 anchors.bottom: parent.bottom
                 width: parent.width * value
                 height: 4
                 color: "#49f"
                 Behavior on opacity {NumberAnimation {duration: 100}}
             }
         }

         // File dialog for selecting image file from local file system
         FileDialog {
             id: fileDialog
             title: "Select image file to upload"
             nameFilters: [ "Image files (*.png *.jpg *.jpeg)", "All files (*)" ]

             onSelectionAccepted: {
                 var pathParts = fileUrl.toString().split("/");
                 var fileName = pathParts[pathParts.length - 1];
                 var fileObject = {
                     objectType: "objects.image",
                     name: fileName,
                     localPath: fileUrl.toString()
                 }
                 var reply = client.create(fileObject);
                 reply.finished.connect(function() {
                     var uploadData = {
                         file: { fileName: fileName },
                         targetFileProperty: {
                             objectType: "objects.image",
                             id: reply.data.id,
                             propertyName: "file"
                         },
                     };

                     imagesUrl[reply.data.id] = reply.data.localPath

                     var uploadReply = client.uploadFile(uploadData, fileUrl)
                     progressBar.opacity = 1
                     uploadReply.progress.connect(function(progress, total) {
                         progressBar.value = progress/total
                     })
                     uploadReply.finished.connect(function() {
                         var tmp = enginioModel.query; enginioModel.query = null; enginioModel.query = tmp;
                         progressBar.opacity = 0
                     })
                 })
             }
         }

         states: [
             State {
                 name: "view"
                 PropertyChanges {
                     target: listLayout
                     x: -root.width
                 }
             }
         ]
     }
     function sizeStringFromFile(fileData) {
         var str = [];
         if (fileData && fileData.fileSize) {
             str.push("Size: ");
             str.push(fileData.fileSize);
             str.push(" bytes");
         }
         return str.join("");
     }

     function doubleDigitNumber(number) {
         if (number < 10)
             return "0" + number;
         return number;
     }

     function timeStringFromFile(fileData) {
         var str = [];
         if (fileData && fileData.createdAt) {
             var date = new Date(fileData.createdAt);
             if (date) {
                 str.push("Uploaded: ");
                 str.push(date.toDateString());
                 str.push(" ");
                 str.push(doubleDigitNumber(date.getHours()));
                 str.push(":");
                 str.push(doubleDigitNumber(date.getMinutes()));
             }
         }
         return str.join("");
     }
 }