ProjectExplorer: Overlay the original icon for missing files

QmlProject could be edited manually to add files into the project.
In case of the files are mising in the file system (or if there's
a typo in the file path) file names still shown in the project
explorer without any information. This patch brings a small overlay
on top of the original icon to notify the users that the file doesn't
exist.

Task-number: QDS-10344
Change-Id: Ia73699b048725bcc70a1ee0f52c34b55b081a779
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>
Reviewed-by: Qt CI Patch Build Bot <ci_patchbuild_bot@qt.io>

src/plugins/projectexplorer/project.h

@@ -49,7 +49,8 @@ public:
     enum ModelRoles {
         // Absolute file path
         FilePathRole = QFileSystemModel::FilePathRole,
-        isParsingRole
+        isParsingRole,
+        UseUnavailableMarkerRole,
     };
 
     Project(const QString &mimeType, const Utils::FilePath &fileName);

src/plugins/projectexplorer/projectmodels.cpp

@@ -193,6 +193,7 @@ QVariant FlatModel::data(const QModelIndex &index, int role) const
         return {};
 
     const FolderNode * const folderNode = node->asFolderNode();
+    const FileNode * const fileNode = node->asFileNode();
     const ContainerNode * const containerNode = node->asContainerNode();
     const Project * const project = containerNode ? containerNode->project() : nullptr;
     const Target * const target = project ? project->activeTarget() : nullptr;
@@ -246,6 +247,8 @@ QVariant FlatModel::data(const QModelIndex &index, int role) const
         return node->filePath().toString();
     case Project::isParsingRole:
         return project && bs ? bs->isParsing() && !project->needsConfiguration() : false;
+    case Project::UseUnavailableMarkerRole:
+        return fileNode ? fileNode->useUnavailableMarker() : false;
     }
     return {};
 }
@@ -923,4 +926,3 @@ const QLoggingCategory &FlatModel::logger()
 
 } // namespace Internal
 } // namespace ProjectExplorer
-

src/plugins/projectexplorer/projectnodes.cpp

@@ -260,6 +260,16 @@ void FileNode::setHasError(bool error) const
     m_hasError = error;
 }
 
+bool FileNode::useUnavailableMarker() const
+{
+    return m_useUnavailableMarker;
+}
+
+void FileNode::setUseUnavailableMarker(bool useUnavailableMarker)
+{
+    m_useUnavailableMarker = useUnavailableMarker;
+}
+
 /*!
   Returns \c true if the file is automatically generated by a compile step.
   */
@@ -382,6 +392,7 @@ FileNode::FileNode(const Utils::FilePath &filePath, const FileType fileType) :
     m_fileType(fileType)
 {
     setFilePath(filePath);
+    setUseUnavailableMarker(!filePath.needsDevice() && !filePath.exists());
     setListInProject(true);
     if (fileType == FileType::Project)
         setPriority(DefaultProjectFilePriority);

src/plugins/projectexplorer/projectnodes.h

@@ -204,10 +204,14 @@ public:
     QIcon icon() const;
     void setIcon(const QIcon icon);
 
+    bool useUnavailableMarker() const;
+    void setUseUnavailableMarker(bool useUnavailableMarker);
+
 private:
     FileType m_fileType;
     mutable QIcon m_icon;
     mutable bool m_hasError = false;
+    bool m_useUnavailableMarker = false;
 };
 
 // Documentation inside.

src/plugins/projectexplorer/projecttreewidget.cpp

@@ -72,8 +72,18 @@ public:
 
     void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const override
     {
-        QStyledItemDelegate::paint(painter, option, index);
+        const bool useUnavailableMarker = index.data(Project::UseUnavailableMarkerRole).toBool();
+        if (useUnavailableMarker) {
+            QStyleOptionViewItem opt = option;
+            opt.palette.setColor(QPalette::Text, creatorTheme()->color(Theme::TextColorDisabled));
+            QStyledItemDelegate::paint(painter, opt, index);
+            static const QPixmap pixmap
+                = QApplication::style()->standardIcon(QStyle::SP_BrowserStop).pixmap(10);
+            painter->drawPixmap(option.rect.topLeft(), pixmap);
+            return;
+        }
 
+        QStyledItemDelegate::paint(painter, option, index);
         if (index.data(Project::isParsingRole).toBool()) {
             QStyleOptionViewItem opt = option;
             initStyleOption(&opt, index);