Merge lp:~ahayzen/ubuntu-ui-extras/tabs-add-dnd into lp:~phablet-team/ubuntu-ui-extras/tabs

[Andrew Hayzen]

* Add drag and drop support to tabs component

* Add drag and drop support to tabs component

[Andrew Hayzen (ahayzen)]

I wonder if it should be
visible: !Window.active || dimmed
or
visible: !Window.active || (dimmed && !dropArea.containsDrag)

For the Rectangle dimming the TabBar

=== modified file 'modules/Ubuntu/Components/Extras/TabsBar.qml'
--- modules/Ubuntu/Components/Extras/TabsBar.qml	2016-12-08 14:26:41 +0000
+++ modules/Ubuntu/Components/Extras/TabsBar.qml	2017-01-06 16:37:25 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2016 Canonical Ltd
+ * Copyright (C) 2016, 2017 Canonical Ltd
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
@@ -22,6 +22,8 @@
 import Ubuntu.Components 1.3
 import "TabsBar" as LocalTabs
 
+import Ubuntu.Components.Extras 0.3
+
 Rectangle {
     id: tabsBar
 
@@ -35,15 +37,40 @@
     property color highlightColor: Qt.rgba(actionColor.r, actionColor.g, actionColor.b, 0.1)
     /* 'model' needs to have the following members:
          property int selectedIndex
+         function addExistingTab(var tab)
          function selectTab(int index)
          function removeTab(int index)
+         function removeTabWithoutDestroying(int index)
          function moveTab(int from, int to)
+
+         removeTabWithoutDestroying is useful when a tab is being removed due
+         to moving, so you don't want the content to be destroyed
     */
     property var model
     property list<Action> actions
+    property bool dimmed: false
+
+    /* To enable drag and drop set to enabled
+     *
+     * Use expose to set any information you need the DropArea to access
+     * Then use drag.source.expose.myproperty
+     *
+     * Set mimeType to one of the keys in the DropArea's you want to accept
+     *
+     * Set a function for previewUrlFromIndex which is given the index
+     * and returns a url to an image, which will be shown in the handle
+     */
+    readonly property alias dragAndDrop: dragAndDropImpl
+
+    LocalTabs.DragAndDropSettings {
+        id: dragAndDropImpl
+    }
 
     property string fallbackIcon: ""
 
+    property Component windowFactory: null
+    property var windowFactoryProperties: ({})  // any addition properties such as height, width
+
     signal contextMenu(var tabDelegate, int index)
 
     function iconNameFromModelItem(modelItem, index) {
@@ -106,6 +133,7 @@
             right: tabs.overflow ? rightStepper.left : actions.left
         }
         interactive: false
+        objectName: "tabListView"
         orientation: ListView.Horizontal
         clip: true
         highlightMoveDuration: UbuntuAnimation.FastDuration
@@ -139,16 +167,21 @@
         model: tabsBar.model
         delegate: MouseArea {
             id: tabMouseArea
+            objectName: "tabDelegate"
 
+            acceptedButtons: Qt.LeftButton | Qt.RightButton | Qt.MiddleButton
             width: tab.width
             height: tab.height
             drag {
-                target: tabs.count > 1 && tab.isFocused ? tab : null
-                axis: Drag.XAxis
+                target: (tabs.count > 1 || dragAndDrop.enabled) && tab.isFocused ? tab : null
+                axis: dragAndDrop.enabled ? Drag.XAndYAxis : Drag.XAxis
                 minimumX: tab.isDragged ? -tab.width/2 : -Infinity
                 maximumX: tab.isDragged ? tabs.width - tab.width/2 : Infinity
             }
             z: tab.isFocused ? 1 : 0
+
+            readonly property int tabIndex: index  // for autopilot
+
             Binding {
                 target: tabsBar
                 property: "selectedTabX"
@@ -161,6 +194,13 @@
                 value: tab.width
                 when: tab.isFocused
             }
+            NumberAnimation {
+                id: resetVerticalAnimation
+                target: tab
+                duration: 250
+                property: "y"
+                to: 0
+            }
 
             onPressed: {
                 if (mouse.button === Qt.LeftButton) {
@@ -171,6 +211,7 @@
                     tabsBar.model.removeTab(index)
                 }
             }
+            onReleased: resetVerticalAnimation.start()
             onWheel: {
                 if (wheel.angleDelta.y >= 0) {
                     tabsBar.model.selectTab(tabsBar.model.selectedIndex - 1);
@@ -183,12 +224,17 @@
 
             LocalTabs.Tab {
                 id: tab
+                objectName: "tabItem"
 
                 anchors.left: tabMouseArea.left
                 implicitWidth: tabs.availableWidth / 2
                 width: tabs.overflow ? tabs.availableWidth / tabs.maximumTabsCount : Math.min(tabs.maximumTabWidth, implicitWidth)
                 height: tabs.height
 
+                // Reference the tab and window so that the dropArea can determine what to do
+                readonly property var thisTab: tabsBar.model.get(index)
+                readonly property var thisWindow: dragAndDrop.thisWindow
+
                 property bool isDragged: tabMouseArea.drag.active
                 Drag.active: tab.isDragged
                 Drag.source: tabMouseArea
@@ -243,6 +289,67 @@
                     }
                 }
             }
+
+            DragHelper {
+                id: dragHelper
+                expectedAction: dragAndDrop.expectedAction
+                mimeType: dragAndDrop.mimeType
+                previewBorderWidth: dragAndDrop.previewBorderWidth
+                previewSize: dragAndDrop.previewSize
+                previewTopCrop: dragAndDrop.previewTopCrop
+                previewUrl: dragAndDrop.previewUrlFromIndex(index)
+                source: tab
+            }
+
+            onPositionChanged: {
+                if (!dragAndDrop.enabled || !tabMouseArea.drag.active) {
+                    return;
+                }
+
+                // Keep the visual tab within maxYDiff of starting point when
+                // dragging vertically so that it doesn't cover other elements
+                // or appear to be detached
+                tab.y = Math.abs(tab.y) > dragAndDrop.maxYDiff ? (tab.y > 0 ? 1 : -1) * dragAndDrop.maxYDiff : tab.y
+
+                // Initiate drag and drop if mouse y has gone further than the height from the object
+                if (mouse.y > height * 2 || mouse.y < -height) {
+                    // Reset visual position of tab delegate
+                    resetVerticalAnimation.start();
+
+                    var dropAction = dragHelper.execDrag(index);
+
+                    // IgnoreAction - no DropArea accepted so New Window
+                    // MoveAction   - DropArea accept but different window
+                    // CopyAction   - DropArea accept but same window
+
+                    if (dropAction === Qt.MoveAction) {
+                        // Moved into another window
+
+                        // Just remove from model and do not destroy
+                        // as webview is used in other window
+                        tabsBar.model.removeTabWithoutDestroying(index);
+                    } else if (dropAction === Qt.CopyAction) {
+                        // Moved into the same window
+
+                        // So no action
+                    } else if (dropAction === Qt.IgnoreAction) {
+                        // Moved outside of any window
+
+                        // Create new window and add existing tab
+                        var window = windowFactory.createObject(null, windowFactoryProperties);
+                        window.model.addExistingTab(tab.thisTab);
+                        window.model.selectTab(window.model.count - 1);
+                        window.show();
+
+                        // Just remove from model and do not destroy
+                        // as webview is used in other window
+                        tabsBar.model.removeTabWithoutDestroying(index);
+                    } else {
+                        // Unknown state
+                        console.debug("Unknown drop action:", dropAction);
+                    }
+                }
+            }
         }
     }
 
@@ -290,6 +397,7 @@
             model: tabsBar.actions
 
             LocalTabs.TabButton {
+                objectName: modelData.objectName
                 iconColor: tabsBar.actionColor
                 iconSource: modelData.iconSource
                 onClicked: modelData.trigger()
@@ -303,6 +411,41 @@
         anchors.fill: parent
         color: backgroundColor
         opacity: 0.4
-        visible: !Window.active
+        visible: !Window.active || (dimmed && !dropArea.containsDrag)
+    }
+
+    DropArea {
+        id: dropArea
+        anchors {
+            fill: parent
+        }
+        keys: [dragAndDrop.mimeType]
+
+        onDropped: {
+            // IgnoreAction - no DropArea accepted so New Window
+            // MoveAction   - DropArea accept but different window
+            // CopyAction   - DropArea accept but same window
+            if (drag.source.thisWindow === dragAndDrop.thisWindow) {
+                // Dropped in same window
+                drop.accept(Qt.CopyAction);
+            } else {
+                // Dropped in new window, moving tab
+                tabsBar.model.addExistingTab(drag.source.thisTab);
+                tabsBar.model.selectTab(tabsBar.model.count - 1);
+
+                drop.accept(Qt.MoveAction);
+            }
+        }
+        onEntered: {
+            thisWindow.raise()
+            thisWindow.requestActivate();
+        }
+        onPositionChanged: {
+            if (drag.source.thisWindow === dragAndDrop.thisWindow) {
+                // tab drag is within same window and in chrome
+                // so reorder tabs by setting tab x position
+                drag.source.x = drag.x - (drag.source.width / 2);
+            }
+        }
     }
 }
 
=== added file 'modules/Ubuntu/Components/Extras/TabsBar/DragAndDropSettings.qml'
--- modules/Ubuntu/Components/Extras/TabsBar/DragAndDropSettings.qml	1970-01-01 00:00:00 +0000
+++ modules/Ubuntu/Components/Extras/TabsBar/DragAndDropSettings.qml	2017-01-06 16:37:25 +0000
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2016 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authored-by: Andrew Hayzen <[e-mail]>
+ */
+import QtQuick 2.4
+
+QtObject {
+    property bool enabled: false
+    property var expectedAction: Qt.IgnoreAction | Qt.CopyAction | Qt.MoveAction
+    property int maxYDiff: parent.height / 16
+    property string mimeType: "x-tabsbar/tab"
+    property real previewBorderWidth: units.gu(1)
+    property var previewSize: Qt.size(units.gu(35), units.gu(22.5))
+    property real previewTopCrop: 0
+    property var previewUrlFromIndex: function(index) {
+        return "";
+    }
+    property var thisWindow: null  // Qt 5.7 retrieve from attached property
+}
 
=== modified file 'modules/Ubuntu/Components/Extras/TabsBar/Tab.qml'
--- modules/Ubuntu/Components/Extras/TabsBar/Tab.qml	2016-12-08 14:26:41 +0000
+++ modules/Ubuntu/Components/Extras/TabsBar/Tab.qml	2017-01-06 16:37:25 +0000
@@ -78,6 +78,7 @@
 
     MouseArea {
         id: tabCloseButton
+        objectName: "tabCloseButton"
 
         anchors {
             top: parent.top
 
=== modified file 'modules/Ubuntu/Components/Extras/plugin/CMakeLists.txt'
--- modules/Ubuntu/Components/Extras/plugin/CMakeLists.txt	2016-07-06 08:26:51 +0000
+++ modules/Ubuntu/Components/Extras/plugin/CMakeLists.txt	2017-01-06 16:37:25 +0000
@@ -19,12 +19,16 @@
     photoeditor/photo-edit-thread.cpp
     )
 
+set(TABS_BAR_PLUGIN_SRC
+    tabsbar/drag-helper.cpp
+)
+
 include_directories(
     ${CMAKE_BINARY_DIR}
 )
 
 add_library(ubuntu-ui-extras-plugin SHARED ${PLUGIN_SRC} ${PLUGIN_HDRS}
-            ${EXAMPLE_PLUGIN_SRC} ${PHOTO_EDITOR_PLUGIN_SRC})
+            ${EXAMPLE_PLUGIN_SRC} ${PHOTO_EDITOR_PLUGIN_SRC} ${TABS_BAR_PLUGIN_SRC})
 qt5_use_modules(ubuntu-ui-extras-plugin Core Qml Quick Xml Widgets)
 target_link_libraries(ubuntu-ui-extras-plugin
     ${EXIV2_LIBRARIES}
 
=== modified file 'modules/Ubuntu/Components/Extras/plugin/components.cpp'
--- modules/Ubuntu/Components/Extras/plugin/components.cpp	2015-04-29 15:48:07 +0000
+++ modules/Ubuntu/Components/Extras/plugin/components.cpp	2017-01-06 16:37:25 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012-2013 Canonical, Ltd.
+ * Copyright (C) 2012-2013, 2016 Canonical, Ltd.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -23,6 +23,8 @@
 #include "photoeditor/photo-image-provider.h"
 #include "photoeditor/file-utils.h"
 
+#include "tabsbar/drag-helper.h"
+
 void Components::registerTypes(const char *uri)
 {
     // Example component
@@ -32,6 +34,9 @@
     qmlRegisterType<PhotoData>(uri, 0, 2, "PhotoData");
     qmlRegisterSingletonType<FileUtils>(uri, 0, 2, "FileUtils",
                                         exportFileUtilsSingleton);
+
+    // TabsBar component
+    qmlRegisterType<DragHelper>(uri, 0, 3, "DragHelper");
 }
 
 void Components::initializeEngine(QQmlEngine *engine, const char *uri)
 
=== modified file 'modules/Ubuntu/Components/Extras/plugin/components.h'
--- modules/Ubuntu/Components/Extras/plugin/components.h	2014-11-19 10:14:20 +0000
+++ modules/Ubuntu/Components/Extras/plugin/components.h	2017-01-06 16:37:25 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012-2013 Canonical, Ltd.
+ * Copyright (C) 2012-2013, 2016 Canonical, Ltd.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
 
=== added directory 'modules/Ubuntu/Components/Extras/plugin/tabsbar'
=== added file 'modules/Ubuntu/Components/Extras/plugin/tabsbar/drag-helper.cpp'
--- modules/Ubuntu/Components/Extras/plugin/tabsbar/drag-helper.cpp	1970-01-01 00:00:00 +0000
+++ modules/Ubuntu/Components/Extras/plugin/tabsbar/drag-helper.cpp	2017-01-06 16:37:25 +0000
@@ -0,0 +1,205 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This file is part of webbrowser-app.
+ *
+ * webbrowser-app is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * webbrowser-app is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authored-by: Andrew Hayzen <[e-mail]>
+ */
+
+#include "drag-helper.h"
+
+#include <QtCore/QMimeData>
+#include <QtCore/QPoint>
+#include <QtCore/QSize>
+#include <QtCore/QString>
+#include <QtGui/QDrag>
+#include <QtGui/QDropEvent>
+#include <QtGui/QPainter>
+#include <QtGui/QPen>
+#include <QtGui/QPixmap>
+#include <QtQuick/QQuickItem>
+
+DragHelper::DragHelper()
+    : QObject(),
+    m_active(false),
+    m_dragging(false),
+    m_expected_action(Qt::IgnoreAction),
+    m_mime_type(QStringLiteral("x-tabsbar/tab")),
+    m_preview_border_width(8),
+    m_preview_size(QSizeF(200, 150)),
+    m_preview_top_crop(0),
+    m_preview_url(""),
+    m_source(Q_NULLPTR)
+{
+
+}
+
+QPixmap DragHelper::drawPixmapWithBorder(QPixmap pixmap, int borderWidth, QColor color)
+{
+    // Create a transparent pixmap to draw to
+    QPixmap output(pixmap.width() + borderWidth * 2, pixmap.height() + borderWidth * 2);
+    output.fill(QColor(0, 0, 0, 0));
+
+    // Draw the pixmap with space around the edge for a border
+    QPainter borderPainter(&output);
+    borderPainter.setRenderHint(QPainter::Antialiasing);
+    borderPainter.drawPixmap(borderWidth, borderWidth, pixmap);
+
+    // Define a pen to use for the border
+    QPen borderPen;
+    borderPen.setColor(color);
+    borderPen.setJoinStyle(Qt::MiterJoin);
+    borderPen.setStyle(Qt::SolidLine);
+    borderPen.setWidth(borderWidth);
+
+    // Set the pen and draw the border
+    borderPainter.setPen(borderPen);
+    borderPainter.drawRect(borderWidth / 2, borderWidth / 2,
+                           output.width() - borderWidth, output.height() - borderWidth);
+
+    return output;
+}
+
+Qt::DropAction DragHelper::execDrag(QString tabId)
+{
+    QDrag *drag = new QDrag(m_source);
+
+    // Create a mimedata object to use for the drag
+    QMimeData *mimeData = new QMimeData;
+    mimeData->setData(mimeType(), tabId.toLatin1());
+
+    // Get a bordered pixmap of the previewUrl
+    QSize size = previewSize().toSize();
+
+    QPixmap pixmap = drawPixmapWithBorder(getPreviewUrlAsPixmap(size.width(), size.height()),
+        previewBorderWidth(), QColor(205, 205, 205, 255 * 0.6));  // #cdcdcd
+
+    // Setup the drag and then execute it
+    drag->setHotSpot(QPoint(size.width() * 0.1, size.height() * 0.1));
+    drag->setMimeData(mimeData);
+    drag->setPixmap(pixmap);
+
+    setDragging(true);
+
+    Qt::DropAction action = drag->exec(expectedAction());
+
+    setDragging(false);
+
+    return action;
+}
+
+QPixmap DragHelper::getPreviewUrlAsPixmap(int width, int height)
+{
+    QSize pixmapSize(width, height);
+    QPixmap pixmap(previewUrl());
+
+    if (pixmap.isNull()) {
+        // If loading pixmap failed, draw a white rectangle
+        pixmap = QPixmap(pixmapSize);
+        QPainter painter(&pixmap);
+        painter.eraseRect(0, 0, pixmapSize.width(), pixmapSize.height());
+        painter.fillRect(0, 0, pixmapSize.width(), pixmapSize.height(), QColor(255, 255, 255, 255));
+    } else {
+        // Crop transparent part off the top of the image
+        pixmap = pixmap.copy(0, previewTopCrop(), pixmap.width(), pixmap.height() - previewTopCrop());
+
+        // Scale image to fit the expected size
+        pixmap = pixmap.scaled(pixmapSize, Qt::KeepAspectRatio, Qt::SmoothTransformation);
+    }
+
+    return pixmap;
+}
+
+void DragHelper::setActive(bool active)
+{
+    if (m_active != active) {
+        m_active = active;
+
+        Q_EMIT activeChanged();
+    }
+}
+
+void DragHelper::setDragging(bool dragging)
+{
+    if (m_dragging != dragging) {
+        m_dragging = dragging;
+
+        Q_EMIT draggingChanged();
+    }
+}
+
+void DragHelper::setExpectedAction(Qt::DropAction expectedAction)
+{
+    if (m_expected_action != expectedAction) {
+        m_expected_action = expectedAction;
+
+        Q_EMIT expectedActionChanged();
+    }
+}
+
+void DragHelper::setMimeType(QString mimeType)
+{
+    if (m_mime_type != mimeType) {
+        m_mime_type = mimeType;
+
+        Q_EMIT mimeTypeChanged();
+    }
+}
+
+void DragHelper::setPreviewBorderWidth(int previewBorderWidth)
+{
+    if (m_preview_border_width != previewBorderWidth) {
+        m_preview_border_width = previewBorderWidth;
+
+        Q_EMIT previewBorderWidthChanged();
+    }
+}
+
+void DragHelper::setPreviewSize(QSizeF previewSize)
+{
+    if (m_preview_size != previewSize) {
+        m_preview_size = previewSize;
+
+        Q_EMIT previewSizeChanged();
+    }
+}
+
+void DragHelper::setPreviewTopCrop(int previewTopCrop)
+{
+    if (m_preview_top_crop != previewTopCrop) {
+        m_preview_top_crop = previewTopCrop;
+
+        Q_EMIT previewTopCropChanged();
+    }
+}
+
+void DragHelper::setPreviewUrl(QString previewUrl)
+{
+    if (m_preview_url != previewUrl) {
+        m_preview_url = previewUrl;
+
+        Q_EMIT previewUrlChanged();
+    }
+}
+
+void DragHelper::setSource(QQuickItem *source)
+{
+    if (m_source != source) {
+        m_source = source;
+
+        Q_EMIT sourceChanged();
+    }
+}
+
 
=== added file 'modules/Ubuntu/Components/Extras/plugin/tabsbar/drag-helper.h'
--- modules/Ubuntu/Components/Extras/plugin/tabsbar/drag-helper.h	1970-01-01 00:00:00 +0000
+++ modules/Ubuntu/Components/Extras/plugin/tabsbar/drag-helper.h	2017-01-06 16:37:25 +0000
@@ -0,0 +1,93 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This file is part of webbrowser-app.
+ *
+ * webbrowser-app is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * webbrowser-app is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authored-by: Andrew Hayzen <[e-mail]>
+ */
+
+#ifndef __DRAGHELPER_H__
+#define __DRAGHELPER_H__
+
+#include <QtCore/QSizeF>
+#include <QtCore/QObject>
+#include <QtCore/QString>
+#include <QtGui/QColor>
+#include <QtGui/QMouseEvent>
+
+class QQuickItem;
+
+class DragHelper : public QObject
+{
+    Q_OBJECT
+
+    Q_PROPERTY(bool active READ active WRITE setActive NOTIFY activeChanged)
+    Q_PROPERTY(bool dragging READ dragging NOTIFY draggingChanged)
+    Q_PROPERTY(Qt::DropAction expectedAction READ expectedAction WRITE setExpectedAction NOTIFY expectedActionChanged)
+    Q_PROPERTY(QString mimeType READ mimeType WRITE setMimeType NOTIFY mimeTypeChanged)
+    Q_PROPERTY(int previewBorderWidth READ previewBorderWidth WRITE setPreviewBorderWidth NOTIFY previewBorderWidthChanged)
+    Q_PROPERTY(QSizeF previewSize READ previewSize WRITE setPreviewSize NOTIFY previewSizeChanged)
+    Q_PROPERTY(int previewTopCrop READ previewTopCrop WRITE setPreviewTopCrop NOTIFY previewTopCropChanged)
+    Q_PROPERTY(QString previewUrl READ previewUrl WRITE setPreviewUrl NOTIFY previewUrlChanged)
+    Q_PROPERTY(QQuickItem* source READ source WRITE setSource NOTIFY sourceChanged)
+public:
+    DragHelper();
+    bool active() { return m_active; }
+    bool dragging() { return m_dragging; }
+    Qt::DropAction expectedAction() { return m_expected_action; }
+    QString mimeType() { return m_mime_type; }
+    int previewBorderWidth() { return m_preview_border_width; }
+    QSizeF previewSize() { return m_preview_size; }
+    int previewTopCrop() { return m_preview_top_crop; }
+    QString previewUrl() { return m_preview_url; }
+    QQuickItem *source() { return m_source; }
+Q_SIGNALS:
+    void activeChanged();
+    void draggingChanged();
+    void expectedActionChanged();
+    void mimeTypeChanged();
+    void previewBorderWidthChanged();
+    void previewSizeChanged();
+    void previewTopCropChanged();
+    void previewUrlChanged();
+    void sourceChanged();
+public Q_SLOTS:
+    Q_INVOKABLE Qt::DropAction execDrag(QString tabId);
+    void setActive(bool active);
+    void setExpectedAction(Qt::DropAction expectedAction);
+    void setMimeType(QString mimeType);
+    void setPreviewBorderWidth(int previewBorderWidth);
+    void setPreviewSize(QSizeF previewSize);
+    void setPreviewTopCrop(int previewTopCrop);
+    void setPreviewUrl(QString previewUrl);
+    void setSource(QQuickItem *source);
+private:
+    QPixmap drawPixmapWithBorder(QPixmap pixmap, int borderWidth, QColor color);
+    QPixmap getPreviewUrlAsPixmap(int width, int height);
+    void setDragging(bool dragging);
+
+    bool m_active;
+    bool m_dragging;
+    Qt::DropAction m_expected_action;
+    QString m_mime_type;
+    int m_preview_border_width;
+    QSizeF m_preview_size;
+    int m_preview_top_crop;
+    QString m_preview_url;
+    QQuickItem *m_source;
+};
+
+#endif // __DRAGHELPER_H__
+