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**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
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** This file is part of Qt Creator.
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** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
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import QtQuick 1.0

/* The view displaying the item grid.

The following Qml context properties have to be set:
- listmodel itemLibraryModel
- int itemLibraryIconWidth
- int itemLibraryIconHeight

itemLibraryModel has to have the following structure:

ListModel {
ListElement {
int sectionLibId
string sectionName
list sectionEntries: [
ListElement {
int itemLibId
string itemName
pixmap itemPixmap
},
...
]
}
...
}
*/

Rectangle {
    id: itemsView

    // public

    function scrollView(delta) {
        scrollbar.scroll(-delta / style.scrollbarWheelDeltaFactor)
    }

    function resetView() {
        expandAllEntries()
        scrollbar.reset()
    }

    signal itemSelected(int itemLibId)
    signal itemDragged(int itemLibId)

    signal stopDragAndDrop

    // internal

    signal expandAllEntries

    ItemsViewStyle { id: style }

    color: style.backgroundColor

    /* workaround: without this, a completed drag and drop operation would
result in the drag being continued when QmlView re-gains
focus */
    MouseArea {
        anchors.fill: parent
        hoverEnabled: true
        onEntered: {
            if (!pressed)
                stopDragAndDrop()
            }
            }

                signal selectionUpdated(int itemSectionIndex)

                property int selectedItemLibId: -1
                property int selectionSectionLibId: -1

                function setSelection(itemLibId) {
                    selectedItemLibId = itemLibId
                    selectionSectionLibId = itemLibraryModel.getSectionLibId(itemLibId)
                    selectionUpdated(itemLibraryModel.getItemSectionIndex(itemLibId))
                }

                function unsetSelection() {
                    selectedItemLibId = -1
                    selectionSectionLibId = -1
                    selectionUpdated(-1)
                }

                Connections {
                    target: itemLibraryModel
                    onVisibilityChanged: {
                        if (itemLibraryModel.isItemVisible(selectedItemLibId))
                            setSelection(selectedItemLibId)
                            else
                                unsetSelection()
                        }
                        }

                            /* the following 3 properties are calculated here for performance
reasons and then passed to the section views */
                            property int entriesPerRow: Math.max(1, Math.floor((itemsFlickable.width - 2) / style.cellWidth))
                            property int cellWidth: Math.floor((itemsFlickable.width - 2) / entriesPerRow)
                            property int cellHeight: style.cellHeight

                            Component {
                                id: sectionDelegate

                                SectionView {
                                    id: section

                                    entriesPerRow: itemsView.entriesPerRow
                                    cellWidth: itemsView.cellWidth
                                    cellHeight: itemsView.cellHeight

                                    width: itemsFlickable.width
                                    itemHighlight: selector

                                    property bool containsSelection: (selectionSectionLibId == sectionLibId)

                                    onItemSelected: {
                                        itemsView.setSelection(itemLibId)
                                        itemsView.itemSelected(itemLibId)
                                    }
                                    onItemDragged: {
                                        section.itemSelected(itemLibId)
                                        itemsView.itemDragged(itemLibId)
                                    }

                                    Connections {
                                        target: itemsView
                                        onExpandAllEntries: section.expand()
                                        onSelectionUpdated: {
                                            if (containsSelection) {
                                                section.setSelection(itemSectionIndex)
                                                section.focusSelection(itemsFlickable)
                                            } else
                                                section.unsetSelection()
                                            }
                                            }

                                                Component {
                                                    id: selector

                                                    Selector {
                                                        x: containsSelection? section.currentItem.x:0
                                                        y: containsSelection? section.currentItem.y:0
                                                        width: itemsView.cellWidth
                                                        height: itemsView.cellHeight

                                                        visible: containsSelection
                                                    }
                                                }
                                            }
                            }

                            Flickable {
                                id: itemsFlickable

                                anchors.top: parent.top
                                anchors.topMargin: 3
                                anchors.bottom: parent.bottom
                                anchors.left: parent.left
                                anchors.right: scrollbarFrame.left
                                boundsBehavior: Flickable.DragOverBounds

                                interactive: false
                                contentHeight: col.height

                                /* Limit the content position. Without this, resizing would get the
content position out of scope regarding the scrollbar. */
                                function limitContentPos() {
                                    if (contentY < 0)
                                        contentY = 0;
                                    else {
                                        var maxContentY = Math.max(0, contentHeight - height)
                                        if (contentY > maxContentY)
                                            contentY = maxContentY;
                                    }
                                }
                                onHeightChanged: limitContentPos()
                                onContentHeightChanged: limitContentPos()

                                Column {
                                    id: col

                                    Repeater {
                                        model: itemLibraryModel  // to be set in Qml context
                                        delegate: sectionDelegate
                                    }
                                }
                            }

                            Item {
                                id: scrollbarFrame

                                anchors.top: parent.top
                                anchors.topMargin: 2
                                anchors.bottom: parent.bottom
                                anchors.bottomMargin: 1
                                anchors.right: parent.right
                                width: (itemsFlickable.contentHeight > itemsFlickable.height)? 11:0

                                Scrollbar {
                                    id: scrollbar
                                    anchors.fill: parent
                                    anchors.leftMargin: 1

                                    flickable: itemsFlickable
                                }
                            }
                        }