Overhaul the TaskbarButton QML type

Make the overlay a grouped property, and use QQuickIconLoader
internally to support remote icon sources.

Change-Id: I888244fe5384702dceebe372b0bd0dd50891629a
Reviewed-by: Ivan Vizir <define-true-false@yandex.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Caroline Chao <caroline.chao@digia.com>

4 files changed, 156 insertions, 43 deletions

diff --git a/src/imports/winextras/plugin.cpp b/src/imports/winextras/plugin.cpp
index e3dab0d..348ee4d 100644
--- a/src/imports/winextras/plugin.cpp
+++ b/src/imports/winextras/plugin.cpp
@@ -62,6 +62,7 @@ public:
         qmlRegisterType<QQuickDwmFeatures>(uri, 1, 0, "DwmFeatures");
         qmlRegisterType<QQuickTaskbarButton>(uri, 1, 0, "TaskbarButton");
         qmlRegisterUncreatableType<QWinTaskbarProgress>(uri, 1, 0, "TaskbarProgress", "Cannot create TaskbarProgress - use TaskbarButton.progress instead.");
+        qmlRegisterUncreatableType<QQuickTaskbarOverlay>(uri, 1, 0, "TaskbarOverlay", "Cannot create TaskbarOverlay - use TaskbarButton.overlay instead.");
         qmlRegisterType<QQuickJumpList>(uri, 1, 0, "JumpList");
         qmlRegisterType<QQuickJumpListItem>(uri, 1, 0, "JumpListItem");
         qmlRegisterType<QQuickJumpListCategory>(uri, 1, 0, "JumpListCategory");
diff --git a/src/imports/winextras/qquicktaskbarbutton.cpp b/src/imports/winextras/qquicktaskbarbutton.cpp
index fbae377..278ac51 100644
--- a/src/imports/winextras/qquicktaskbarbutton.cpp
+++ b/src/imports/winextras/qquicktaskbarbutton.cpp
@@ -41,7 +41,6 @@
  ****************************************************************************/
 
 #include "qquicktaskbarbutton_p.h"
-#include <QtWinExtras/private/qwintaskbarbutton_p.h>
 #include <QQuickWindow>
 
 QT_BEGIN_NAMESPACE
@@ -55,72 +54,103 @@ QT_BEGIN_NAMESPACE
 
     \since QtWinExtras 1.0
 
-    The TaskbarButton type enables you to set overlay icons on a taskbar
-    button, to display a progress indicator, and to add a small toolbar to the
-    window thumbnail popup.
+    The TaskbarButton type enables you to set an overlay icon and to display
+    a progress indicator on a taskbar button. An overlay icon indicates change
+    in the state of the application. A progress indicator shows how time-consuming
+    tasks are progressing.
 
-    \sa QWinTaskbarButton
- */
+    \section3 Example
 
-/*!
-    \class QQuickTaskbarButton
-    \internal
+    The following example illustrates how to use TaskbarButton in QML:
+
+    \snippet code/taskbar.qml taskbar_qml
+
+    \image taskbar-button.png Taskbar Button
+
+    \sa QWinTaskbarButton, QWinTaskbarProgress
  */
 
-QQuickTaskbarButton::QQuickTaskbarButton(QQuickItem *parent) :
-    QQuickItem(parent), button(new QWinTaskbarButton(this))
+QQuickTaskbarOverlay::QQuickTaskbarOverlay(QWinTaskbarButton *button, QObject *parent) :
+    QObject(parent), m_button(button)
 {
+    connect(&m_loader, SIGNAL(finished()), SLOT(iconLoaded()));
 }
 
-QQuickTaskbarButton::~QQuickTaskbarButton()
+QUrl QQuickTaskbarOverlay::iconSource() const
 {
+    return m_iconSource;
 }
 
-/*!
-    \qmlproperty string TaskbarButton::progress
+void QQuickTaskbarOverlay::setIconSource(const QUrl &iconSource)
+{
+    if (m_iconSource != iconSource) {
+        m_iconSource = iconSource;
+        emit iconSourceChanged();
+        m_loader.load(m_iconSource, qmlEngine(parent()));
+    }
+}
 
-    The task bar progress indicator.
- */
-QWinTaskbarProgress *QQuickTaskbarButton::progress() const
+QString QQuickTaskbarOverlay::accessibleDescription() const
 {
-    return button->progress();
+    return m_button->overlayAccessibleDescription();
 }
 
-/*!
-    \qmlproperty string TaskbarButton::icon
+void QQuickTaskbarOverlay::setAccessibleDescription(const QString &description)
+{
+    if (accessibleDescription() != description) {
+        m_button->setOverlayAccessibleDescription(description);
+        emit accessibleDescriptionChanged();
+    }
+}
 
-    The overlay icon path.
- */
-QString QQuickTaskbarButton::overlayIcon() const
+void QQuickTaskbarOverlay::iconLoaded()
 {
-    return m_iconPath;
+    QIcon icon = m_loader.icon();
+    if (!icon.isNull())
+        m_button->setOverlayIcon(icon);
 }
 
-void QQuickTaskbarButton::setOverlayIcon(const QString &path)
+QQuickTaskbarButton::QQuickTaskbarButton(QQuickItem *parent) : QQuickItem(parent),
+    m_button(new QWinTaskbarButton(this)), m_overlay(new QQuickTaskbarOverlay(m_button, this))
+{
+}
+
+QQuickTaskbarButton::~QQuickTaskbarButton()
 {
-    m_iconPath = path;
-    button->setOverlayIcon(QIcon(m_iconPath));
 }
 
 /*!
-    \qmlproperty string TaskbarButton::overlayAccessibleDescription
+    \qmlproperty int TaskbarButton::progress.value
+    \qmlproperty int TaskbarButton::progress.minimum
+    \qmlproperty int TaskbarButton::progress.maximum
+    \qmlproperty bool TaskbarButton::progress.visible
+    \qmlproperty bool TaskbarButton::progress.paused
+    \qmlproperty bool TaskbarButton::progress.stopped
+
+    The taskbar progress indicator.
 
-    The description of the overlay for accessibility purposes.
+    \sa QWinTaskbarProgress
  */
-QString QQuickTaskbarButton::overlayAccessibleDescription() const
+QWinTaskbarProgress *QQuickTaskbarButton::progress() const
 {
-    return button->overlayAccessibleDescription();
+    return m_button->progress();
 }
 
-void QQuickTaskbarButton::setOverlayAccessibleDescription(const QString &description)
+/*!
+    \qmlproperty url TaskbarButton::overlay.iconSource
+    \qmlproperty string TaskbarButton::overlay.accessibleDescription
+
+    The overlay icon and a description of the overlay for accessibility purposes.
+ */
+QQuickTaskbarOverlay *QQuickTaskbarButton::overlay() const
 {
-    button->setOverlayAccessibleDescription(description);
+    return m_overlay;
 }
 
 void QQuickTaskbarButton::itemChange(QQuickItem::ItemChange change, const QQuickItem::ItemChangeData &data)
 {
     if (change == ItemSceneChange) {
-        button->setWindow(data.window);
+        m_button->setWindow(data.window);
     }
     QQuickItem::itemChange(change, data);
 }
diff --git a/src/imports/winextras/qquicktaskbarbutton_p.h b/src/imports/winextras/qquicktaskbarbutton_p.h
index 7c01687..d24947d 100644
--- a/src/imports/winextras/qquicktaskbarbutton_p.h
+++ b/src/imports/winextras/qquicktaskbarbutton_p.h
@@ -47,32 +47,59 @@
 #include <QWinTaskbarButton>
 #include <QWinTaskbarProgress>
 
+#include "qquickiconloader_p.h"
+
 QT_BEGIN_NAMESPACE
 
 class QQuickTaskbarButtonPrivate;
 
+class QQuickTaskbarOverlay : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(QUrl iconSource READ iconSource WRITE setIconSource NOTIFY iconSourceChanged)
+    Q_PROPERTY(QString accessibleDescription READ accessibleDescription WRITE setAccessibleDescription NOTIFY accessibleDescriptionChanged)
+
+public:
+    explicit QQuickTaskbarOverlay(QWinTaskbarButton *button, QObject *parent = 0);
+
+    QUrl iconSource() const;
+    void setIconSource(const QUrl &iconSource);
+
+    QString accessibleDescription() const;
+    void setAccessibleDescription(const QString &description);
+
+Q_SIGNALS:
+    void iconSourceChanged();
+    void accessibleDescriptionChanged();
+
+private Q_SLOTS:
+    void iconLoaded();
+
+private:
+    QUrl m_iconSource;
+    QQuickIconLoader m_loader;
+    QWinTaskbarButton *m_button;
+};
+
 class QQuickTaskbarButton : public QQuickItem
 {
     Q_OBJECT
-    Q_PROPERTY(QString overlayIcon READ overlayIcon WRITE setOverlayIcon)
-    Q_PROPERTY(QString overlayAccessibleDescription READ overlayAccessibleDescription WRITE setOverlayAccessibleDescription)
+    Q_PROPERTY(QQuickTaskbarOverlay *overlay  READ overlay CONSTANT)
     Q_PROPERTY(QWinTaskbarProgress *progress READ progress CONSTANT)
 
 public:
-    QQuickTaskbarButton(QQuickItem *parent = 0);
+    explicit QQuickTaskbarButton(QQuickItem *parent = 0);
     ~QQuickTaskbarButton();
+
+    QQuickTaskbarOverlay *overlay() const;
     QWinTaskbarProgress *progress() const;
-    QString overlayIcon() const;
-    void setOverlayIcon(const QString &path);
-    QString overlayAccessibleDescription() const;
-    void setOverlayAccessibleDescription(const QString &description);
 
 protected:
     void itemChange(ItemChange, const ItemChangeData &) Q_DECL_OVERRIDE;
 
 private:
-    QWinTaskbarButton *button;
-    QString m_iconPath;
+    QWinTaskbarButton *m_button;
+    QQuickTaskbarOverlay *m_overlay;
 };
 
 QT_END_NAMESPACE
diff --git a/src/winextras/doc/snippets/code/taskbar.qml b/src/winextras/doc/snippets/code/taskbar.qml
new file mode 100644
index 0000000..98f3d49
--- /dev/null
+++ b/src/winextras/doc/snippets/code/taskbar.qml
@@ -0,0 +1,55 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
+**     of its contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.0
+import QtQuick.Window 2.0
+import QtWinExtras 1.0
+
+//! [taskbar_qml]
+Window {
+    TaskbarButton {
+        overlay.iconSource: "loading.png"
+        overlay.accessibleDescription: "Loading"
+
+        progress.visible: true
+        progress.value: 50
+    }
+}
+//! [taskbar_qml]