Add model data accessor and merge function to VisualModel.

This provides a way to find an override a tempory item when the real
thing appears in the model data.

4 files changed, 110 insertions, 13 deletions

diff --git a/examples/declarative/modelviews/visualdatamodel/Bubble.qml b/examples/declarative/modelviews/visualdatamodel/Bubble.qml
index de2c80763f..da41af8a47 100644
--- a/examples/declarative/modelviews/visualdatamodel/Bubble.qml
+++ b/examples/declarative/modelviews/visualdatamodel/Bubble.qml
@@ -5,6 +5,11 @@ Rectangle {
 
     property int contentHeight: height - senderText.implicitHeight - 2
 
+    function send() {
+        state = "sending"
+        root.sending()
+    }
+
     x: 1;
     width: 477
     height: Math.max(messageText.implicitHeight, 48) + senderText.implicitHeight + 6
@@ -15,6 +20,12 @@ Rectangle {
 
     state: delegateState
 
+    Timer {
+        id: sendTimer
+        interval: 1000
+        onTriggered: root.sent(messageId, sender, message, avatar)
+    }
+
     Item {
         id: avatarItem
 
@@ -70,7 +81,7 @@ Rectangle {
 
                     anchors.fill: parent
 
-                    onClicked:  root.send(editorLoader.item.text)
+                    onClicked: content.send()
                 }
             }
         }
@@ -103,8 +114,10 @@ Rectangle {
             wrapMode: Text.WordWrap
             focus: true
 
-            Keys.onReturnPressed: root.send(text)
-            Keys.onEnterPressed: root.send(text)
+            text: message
+
+            Keys.onReturnPressed: content.send()
+            Keys.onEnterPressed: content.send()
         }
     }
 
@@ -129,12 +142,19 @@ Rectangle {
         text: time
     }
 
-    states: State {
-        name: "composing"
+    states: [
+        State {
+            name: "composing"
+            PropertyChanges { target: editorLoader; sourceComponent: editorComponent }
+            PropertyChanges { target: sendLoader; sourceComponent: sendComponent }
+        },
+        State {
+            name: "sending"
+            PropertyChanges { target: editorLoader; sourceComponent: editorComponent }
+            PropertyChanges { target: sendTimer; running: true }
+        }
 
-        PropertyChanges { target: editorLoader; sourceComponent: editorComponent }
-        PropertyChanges { target: sendLoader; sourceComponent: sendComponent }
-    }
+    ]
 
     transitions: Transition {
         from: "composing"
diff --git a/examples/declarative/modelviews/visualdatamodel/visualdatamodel.qml b/examples/declarative/modelviews/visualdatamodel/visualdatamodel.qml
index 4a3e511db2..0374ac9da6 100644
--- a/examples/declarative/modelviews/visualdatamodel/visualdatamodel.qml
+++ b/examples/declarative/modelviews/visualdatamodel/visualdatamodel.qml
@@ -9,14 +9,26 @@ Rectangle {
     property string sender: "Me"
     property int messageCounter: 0
 
-    function send(message) {
+    function sending() {
         visualModel.insert(visualModel.count, messageBubble)
         newMessage()
         messageView.positionViewAtEnd()
     }
 
+    function sent(messageId, sender, message, avatar) {
+        messageModel.append({
+            "messageId": messageId,
+            "sender": sender,
+            "message": message,
+            "avatar": avatar,
+            "outbound": true,
+            "time": Qt.formatTime(Date.now()),
+            "delegateState": ""
+        })
+    }
+
     function newMessage() {
-        visualModel.appendData({})
+        visualModel.appendData({ "messageId": ++messageCounter })
         var bubble = visualModel.take(visualModel.count - 1, composer)
         messageBubble = bubble
         messageBubble.y = 0     // Override the position set by the view.
@@ -45,6 +57,7 @@ Rectangle {
             id: visualModel
 
             roles: [
+                VisualRole { name: "messageId"; },
                 VisualRole { name: "sender"; defaultValue: root.sender },
                 VisualRole { name: "message"; defaultValue: "" },
                 VisualRole { name: "avatar"; defaultValue: "" },
@@ -55,6 +68,28 @@ Rectangle {
 
             model: ListModel { id: messageModel }
             delegate: Bubble {}
+
+            onUpdated: {
+                var delta = 0
+                for (var i = 0; i < inserts.length; ++i) {
+                    for (var j = inserts[i].start - delta; j < inserts[i].end - delta; ++j) {
+                        var message = visualModel.get(j)
+                        if (!message.outbound)
+                            continue;
+                        for (var k = inserts[i].start - 1 - delta; k >= 0; ++k) {
+                            var existing = visualModel.get(k);
+                            if (!existing.outbound)
+                                continue;
+                            if (message.messageId == existing.messageId) {
+                                visualModel.merge(j, k)
+                                ++delta
+                                --j
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
         }
 
 //        add: Transition {
@@ -73,6 +108,7 @@ Rectangle {
             var message = script.get(scriptIndex);
 
             messageModel.append({
+                "messageId": -1,
                 "sender": message.sender,
                 "message": message.message,
                 "avatar": message.avatar,
diff --git a/src/declarative/items/qsgvisualitemmodel.cpp b/src/declarative/items/qsgvisualitemmodel.cpp
index c2328e70e8..3a3b1596f8 100644
--- a/src/declarative/items/qsgvisualitemmodel.cpp
+++ b/src/declarative/items/qsgvisualitemmodel.cpp
@@ -73,11 +73,13 @@ QHash<QObject*, QSGVisualModelAttached*> QSGVisualModelAttached::attachedPropert
 class VDMDelegateDataType : public QDeclarativeOpenMetaObjectType
 {
 public:
-    VDMDelegateDataType(const QMetaObject *base, QDeclarativeEngine *engine) : QDeclarativeOpenMetaObjectType(base, engine) {}
+    VDMDelegateDataType(const QMetaObject *base, QDeclarativeEngine *engine) : QDeclarativeOpenMetaObjectType(base, engine), m_caching(false) {}
 
     void propertyCreated(int, QMetaPropertyBuilder &prop) {
-        prop.setWritable(false);
+        prop.setWritable(m_caching);
     }
+
+    bool m_caching;
 };
 
 class QSGVisualModelPartsMetaObject : public QDeclarativeOpenMetaObject
@@ -400,6 +402,7 @@ public:
             ensureRoles();
             QHash<QByteArray, int> roleNames = m_roleNames;
             QSGVisualModelPrivate *parent = QSGVisualModelPrivate::get(static_cast<QSGVisualModel *>(q_ptr->parent()));
+            m_delegateDataType->m_caching = true;
             for (QList<QSGVisualModelRole *>::iterator it = parent->roles.begin(); it != parent->roles.end(); ++it) {
                 QByteArray name = (*it)->name().toUtf8();
                 int propId = m_delegateDataType->createProperty(name) - m_delegateDataType->propertyOffset();
@@ -409,7 +412,7 @@ public:
                     roleNames.erase(it);
                 }
             }
-
+            m_delegateDataType->m_caching = false;
 
             if (m_roleNames.count()) {
                 QHash<QByteArray, int>::const_iterator it = roleNames.begin();
@@ -514,6 +517,7 @@ QSGVisualModelData *QSGVisualModelPrivate::createScriptData(QDeclarativeComponen
         delegateDataType = new VDMDelegateDataType(
                     &QSGVisualModelData::staticMetaObject,
                     context ? context->engine() : qmlEngine(q));
+        delegateDataType->m_caching = true;
         for (QList<QSGVisualModelRole *>::iterator it = roles.begin(); it != roles.end(); ++it)
             delegateDataType->createProperty((*it)->name().toUtf8());
     }
@@ -655,6 +659,23 @@ QSGItem *QSGVisualModel::take(int index, QSGItem *parent)
     return i;
 }
 
+QScriptValue QSGVisualModel::get(int index)
+{
+    Q_D(QSGVisualModel);
+    QDeclarativeEngine *dengine = d->context ? d->context->engine() : qmlEngine(this);
+    QScriptEngine *engine = QDeclarativeEnginePrivate::getScriptEngine(dengine);
+    int offset = 0;
+    int internalIndex = 0;
+    QDeclarativeCompositeRange range = d->at(index, &offset, &internalIndex);
+    if (range.internal()) {
+        return engine->newQObject(d->children[internalIndex].data);
+    } else {
+        return engine->newQObject(
+                new QSGVisualModelData(range.index + offset, static_cast<QSGVisualData *>(range.list)),
+                QScriptEngine::ScriptOwnership);
+    }
+}
+
 QSGVisualModel::ReleaseFlags QSGVisualModel::release(QObject *object)
 {
     Q_D(QSGVisualModel);
@@ -989,6 +1010,24 @@ void QSGVisualModel::move(int from, int to, int count)
     }
 }
 
+void QSGVisualModel::merge(int from, int to)
+{
+    Q_D(QSGVisualModel);
+    if (from == to)
+        return;
+    if (!d->transaction)
+        d->childrenChanged = false;
+    if (!d->merge(from, to)) {
+        qmlInfo(this) << "Items cannot be merged" << from << to;
+    } else if (d->transaction) {
+        d->transactionChanges.insertRemove(from, 1);
+    } else {
+        emit itemsRemoved(from, 1);
+        if (d->childrenChanged)
+            emit childrenChanged();
+    }
+}
+
 void QSGVisualModel::_q_itemsInserted(QSGVisualData *model, int index, int count)
 {
     Q_D(QSGVisualModel);
diff --git a/src/declarative/items/qsgvisualitemmodel_p.h b/src/declarative/items/qsgvisualitemmodel_p.h
index d4a7084fa3..cc8a93c8d9 100644
--- a/src/declarative/items/qsgvisualitemmodel_p.h
+++ b/src/declarative/items/qsgvisualitemmodel_p.h
@@ -109,6 +109,7 @@ public:
 
     static QSGVisualModelAttached *qmlAttachedProperties(QObject *obj);
 
+    Q_INVOKABLE QScriptValue get(int index);
     Q_INVOKABLE QSGItem *item(int index, bool complete = true);
     Q_INVOKABLE QSGItem *item(int index, const QByteArray &viewId, bool complete = true);
     Q_INVOKABLE QSGItem *take(int index, QSGItem *parent = 0);
@@ -124,6 +125,7 @@ public Q_SLOTS:
     void insert(int index, QDeclarativeComponent *delegate, const QScriptValue &data);
     void remove(int index, int count);
     void move(int from, int to, int count);
+    void merge(int from, int to);
 
 Q_SIGNALS:
     void childrenChanged();