QtSupport: move example image loading from delegate to model

Change-Id: I287336b4d36d648666093a4894ab131b8999ca98
Reviewed-by: hjk <hjk@qt.io>

src/plugins/qtsupport/exampleslistmodel.cpp

@@ -25,9 +25,15 @@
 
 #include "exampleslistmodel.h"
 
+#include "screenshotcropper.h"
+
+#include <QBuffer>
 #include <QDebug>
 #include <QDir>
 #include <QFile>
+#include <QFutureWatcher>
+#include <QImageReader>
+#include <QPixmapCache>
 #include <QUrl>
 #include <QXmlStreamReader>
 
@@ -39,6 +45,7 @@
 
 #include <utils/algorithm.h>
 #include <utils/environment.h>
+#include <utils/fileutils.h>
 #include <utils/qtcassert.h>
 
 #include <algorithm>
@@ -46,6 +53,8 @@
 namespace QtSupport {
 namespace Internal {
 
+const QSize ExamplesListModel::exampleImageSize(188, 145);
+
 static bool debugExamples()
 {
     static bool isDebugging = qEnvironmentVariableIsSet("QTC_DEBUG_EXAMPLESMODEL");
@@ -303,6 +312,7 @@ void ExamplesListModel::parseExamples(QXmlStreamReader *reader,
                 item.hasSourceCode = !item.projectPath.isEmpty();
                 item.projectPath = relativeOrInstallPath(item.projectPath, projectsOffset, examplesInstallPath);
                 item.imageUrl = attributes.value(QLatin1String("imageUrl")).toString();
+                QPixmapCache::remove(item.imageUrl);
                 item.docUrl = attributes.value(QLatin1String("docUrl")).toString();
                 item.isHighlighted = attributes.value(QLatin1String("isHighlighted")).toString() == QLatin1String("true");
 
@@ -356,6 +366,7 @@ void ExamplesListModel::parseDemos(QXmlStreamReader *reader,
                 item.hasSourceCode = !item.projectPath.isEmpty();
                 item.projectPath = relativeOrInstallPath(item.projectPath, projectsOffset, demosInstallPath);
                 item.imageUrl = attributes.value(QLatin1String("imageUrl")).toString();
+                QPixmapCache::remove(item.imageUrl);
                 item.docUrl = attributes.value(QLatin1String("docUrl")).toString();
                 item.isHighlighted = attributes.value(QLatin1String("isHighlighted")).toString() == QLatin1String("true");
             } else if (reader->name() == QLatin1String("fileToOpen")) {
@@ -400,6 +411,7 @@ void ExamplesListModel::parseTutorials(QXmlStreamReader *reader, const QString &
                 item.projectPath.prepend(slash);
                 item.projectPath.prepend(projectsOffset);
                 item.imageUrl = attributes.value(QLatin1String("imageUrl")).toString();
+                QPixmapCache::remove(item.imageUrl);
                 item.docUrl = attributes.value(QLatin1String("docUrl")).toString();
                 item.isVideo = attributes.value(QLatin1String("isVideo")).toString() == QLatin1String("true");
                 item.videoUrl = attributes.value(QLatin1String("videoUrl")).toString();
@@ -426,6 +438,12 @@ void ExamplesListModel::parseTutorials(QXmlStreamReader *reader, const QString &
     }
 }
 
+static QString resourcePath()
+{
+    // normalize paths so QML doesn't freak out if it's wrongly capitalized on Windows
+    return Utils::FileUtils::normalizePathName(Core::ICore::resourcePath());
+}
+
 void ExamplesListModel::updateExamples()
 {
     QString examplesInstallPath;
@@ -605,8 +623,30 @@ QVariant ExamplesListModel::data(const QModelIndex &index, int role) const
     {
     case Qt::DisplayRole: // for search only
         return QString(prefixForItem(item) + item.name + ' ' + item.tags.join(' '));
-    case Qt::UserRole:
+    case ExampleItemRole:
         return QVariant::fromValue<ExampleItem>(item);
+    case ExampleImageRole: {
+        QPixmap pixmap;
+        if (QPixmapCache::find(item.imageUrl, &pixmap))
+            return pixmap;
+        pixmap.load(item.imageUrl);
+        if (pixmap.isNull())
+            pixmap.load(resourcePath() + "/welcomescreen/widgets/" + item.imageUrl);
+        if (pixmap.isNull()) {
+            QByteArray fetchedData = Core::HelpManager::fileData(item.imageUrl);
+            if (!fetchedData.isEmpty()) {
+                QBuffer imgBuffer(&fetchedData);
+                imgBuffer.open(QIODevice::ReadOnly);
+                QImageReader reader(&imgBuffer);
+                QImage img = reader.read();
+                img = ScreenshotCropper::croppedImage(img, item.imageUrl,
+                                                      ExamplesListModel::exampleImageSize);
+                pixmap = QPixmap::fromImage(img);
+            }
+        }
+        QPixmapCache::insert(item.imageUrl, pixmap);
+        return pixmap;
+    }
     default:
         return QVariant();
     }
@@ -666,7 +706,8 @@ ExamplesListModelFilter::ExamplesListModelFilter(ExamplesListModel *sourceModel,
 
 bool ExamplesListModelFilter::filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const
 {
-    const ExampleItem item = sourceModel()->index(sourceRow, 0, sourceParent).data(Qt::UserRole).value<ExampleItem>();
+    const ExampleItem item = sourceModel()->index(sourceRow, 0, sourceParent).data(
+                ExamplesListModel::ExampleItemRole).value<ExampleItem>();
 
     if (m_showTutorialsOnly && item.type != Tutorial)
         return false;

src/plugins/qtsupport/exampleslistmodel.h

@@ -125,6 +125,11 @@ class ExamplesListModel : public QAbstractListModel
     Q_OBJECT
 
 public:
+    enum ExampleListDataRole {
+        ExampleItemRole = Qt::UserRole,
+        ExampleImageRole = Qt::UserRole + 1
+    };
+
     explicit ExamplesListModel(QObject *parent);
 
     int rowCount(const QModelIndex &parent = QModelIndex()) const final;
@@ -135,6 +140,8 @@ public:
     QStringList exampleSets() const;
     ExampleSetModel *exampleSetModel() { return &m_exampleSetModel; }
 
+    static const QSize exampleImageSize;
+
 signals:
     void selectedExampleSetChanged(int);
 

src/plugins/qtsupport/gettingstartedwelcomepage.cpp

@@ -55,7 +55,6 @@
 #include <QLabel>
 #include <QMessageBox>
 #include <QPainter>
-#include <QPixmapCache>
 #include <QPointer>
 #include <QPushButton>
 #include <QStyledItemDelegate>
@@ -369,7 +368,7 @@ class ExampleDelegate : public QStyledItemDelegate
 public:
     void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const final
     {
-        const ExampleItem item = index.data(Qt::UserRole).value<ExampleItem>();
+        const ExampleItem item = index.data(ExamplesListModel::ExampleItemRole).value<ExampleItem>();
         const QRect rc = option.rect;
 
         // Quick hack for empty items in the last row.
@@ -414,29 +413,9 @@ public:
 
         // The pixmap.
         if (offset == 0) {
-            const QSize requestSize(188, 145);
+            QPixmap pm = index.data(ExamplesListModel::ExampleImageRole).value<QPixmap>();
-
+            QRect inner(x + 11, y - offset, ExamplesListModel::exampleImageSize.width(),
-            QPixmap pm;
+                        ExamplesListModel::exampleImageSize.height());
-            if (QPixmap *foundPixmap = m_pixmapCache.find(item.imageUrl)) {
-                pm = *foundPixmap;
-            } else {
-                pm.load(item.imageUrl);
-                if (pm.isNull())
-                    pm.load(resourcePath() + "/welcomescreen/widgets/" + item.imageUrl);
-                if (pm.isNull()) {
-                    // FIXME: Make async
-                    QByteArray fetchedData = HelpManager::fileData(item.imageUrl);
-                    QBuffer imgBuffer(&fetchedData);
-                    imgBuffer.open(QIODevice::ReadOnly);
-                    QImageReader reader(&imgBuffer);
-                    QImage img = reader.read();
-                    img = ScreenshotCropper::croppedImage(img, item.imageUrl, requestSize);
-                    pm = QPixmap::fromImage(img);
-                }
-                m_pixmapCache.insert(item.imageUrl, pm);
-            }
-
-            QRect inner(x + 11, y - offset, requestSize.width(), requestSize.height());
             QRect pixmapRect = inner;
             if (!pm.isNull()) {
                 painter->setPen(foregroundColor2);
@@ -576,7 +555,6 @@ private:
     mutable QRect m_currentArea;
     mutable QPointer<QAbstractItemView> m_currentWidget;
     mutable QVector<QPair<QString, QRect>> m_currentTagRects;
-    mutable QPixmapCache m_pixmapCache;
 };
 
 class ExamplesPageWidget : public QWidget