add cancel button for ongoing docset downloads

src/libs/ui/docsetsdialog.cpp

@@ -67,6 +67,7 @@ constexpr int CacheTimeout = 24 * 60 * 60 * 1000; // 24 hours in microseconds
 const char DocsetNameProperty[] = "docsetName";
 const char DownloadTypeProperty[] = "downloadType";
 const char DownloadPreviousReceived[] = "downloadPreviousReceived";
+const char DownloadTotalSize[] = "downloadTotalSize";
 const char ListItemIndexProperty[] = "listItem";
 }
 
@@ -437,11 +438,12 @@ void DocsetsDialog::downloadProgress(qint64 received, qint64 total)
 
     qint64 previousReceived = 0;
     const QVariant previousReceivedVariant = reply->property(DownloadPreviousReceived);
-    if (!previousReceivedVariant.isValid())
+    if (!previousReceivedVariant.isValid()) {
+        reply->setProperty(DownloadTotalSize, total);
         m_combinedTotal += total;
-    else
+    } else {
         previousReceived = previousReceivedVariant.toLongLong();
-
+    }
     m_combinedReceived += received - previousReceived;
     reply->setProperty(DownloadPreviousReceived, received);
 
@@ -572,6 +574,8 @@ void DocsetsDialog::setupAvailableDocsetsTab()
     using Registry::DocsetRegistry;
 
     ui->availableDocsetList->setItemDelegate(new ProgressItemDelegate(this));
+    ProgressItemDelegate* del = static_cast<ProgressItemDelegate*>(ui->availableDocsetList->itemDelegate());
+    connect(del, &ProgressItemDelegate::cancelButtonClicked, this, &DocsetsDialog::cancelDownload);
 
     connect(m_docsetRegistry, &DocsetRegistry::docsetUnloaded, this, [this](const QString name) {
         QListWidgetItem *item = findDocsetListItem(name);
@@ -702,6 +706,28 @@ QNetworkReply *DocsetsDialog::download(const QUrl &url)
     return reply;
 }
 
+void DocsetsDialog::cancelDownload(const QModelIndex &index)
+{
+    // Find and delete download jobs corresponding to index
+    for (QNetworkReply *reply : m_replies) {
+        if (reply->property(ListItemIndexProperty).toInt() == index.row()
+                && reply->property(DownloadTypeProperty).toInt() == DownloadDocset) {
+            QListWidgetItem *listItem = ui->availableDocsetList->item(index.row());
+            listItem->setData(ProgressItemDelegate::ShowProgressRole, false);
+            delete m_tmpFiles.take(reply->property(DocsetNameProperty).toString());
+            reply->abort();
+
+            m_combinedReceived -= reply->property(DownloadPreviousReceived).toLongLong();
+            m_combinedTotal -= reply->property(DownloadTotalSize).toLongLong();
+        }
+    }
+
+    // As the current download is cancelled, unselect the current selected item
+    // This also triggers selectionChanged() and the state of downloadDocsetsButton
+    // is recomputed on the next selection
+    ui->availableDocsetList->selectionModel()->clearSelection();
+}
+
 void DocsetsDialog::cancelDownloads()
 {
     for (QNetworkReply *reply : m_replies) {

src/libs/ui/docsetsdialog.h

@@ -112,6 +112,7 @@ private slots:
     bool updatesAvailable() const;
 
     QNetworkReply *download(const QUrl &url);
+    void cancelDownload(const QModelIndex &index);
     void cancelDownloads();
 
     void loadUserFeedList();

src/libs/ui/progressitemdelegate.cpp

@@ -24,7 +24,10 @@
 #include "progressitemdelegate.h"
 
 #include <QPainter>
+#include <QEvent>
 #include <QProgressBar>
+#include <QPushButton>
+#include <QMouseEvent>
 
 using namespace Zeal::WidgetUi;
 
@@ -51,7 +54,7 @@ void ProgressItemDelegate::paint(QPainter *painter, const QStyleOptionViewItem &
 
     // Adjust maximum text width
     QStyleOptionViewItem styleOption = option;
-    styleOption.rect.setRight(styleOption.rect.right() - progressBarWidth);
+    styleOption.rect.setRight(styleOption.rect.right() - progressBarWidth - cancelButtonWidth);
 
     // Size progress bar
     QScopedPointer<QProgressBar> renderer(new QProgressBar());
@@ -69,7 +72,28 @@ void ProgressItemDelegate::paint(QPainter *painter, const QStyleOptionViewItem &
     painter->translate(styleOption.rect.topRight());
     renderer->render(painter);
 
+    // Button
+    QScopedPointer<QPushButton> buttonRenderer(new QPushButton(tr("Cancel")));
+    buttonRenderer->resize(cancelButtonWidth, styleOption.rect.height());
+
+    painter->translate(progressBarWidth, 0);
+    buttonRenderer->render(painter);
     painter->restore();
 
     QStyledItemDelegate::paint(painter, styleOption, index);
 }
+
+bool ProgressItemDelegate::editorEvent(QEvent *event, QAbstractItemModel *model,
+                                       const QStyleOptionViewItem &option, const QModelIndex &index)
+{
+    QMouseEvent* mouseEvent = static_cast<QMouseEvent*>(event);
+    QRect cancelBounds = option.rect;
+    cancelBounds.setLeft(cancelBounds.right() - cancelButtonWidth);
+
+    if (event->type() == QEvent::MouseButtonRelease
+            && index.model()->data(index, ShowProgressRole).toBool()
+            && cancelBounds.contains(mouseEvent->pos()))
+        emit cancelButtonClicked(index);
+
+    return QStyledItemDelegate::editorEvent(event, model, option, index);
+}

src/libs/ui/progressitemdelegate.h

@@ -44,8 +44,15 @@ class ProgressItemDelegate : public QStyledItemDelegate
     void paint(QPainter *painter, const QStyleOptionViewItem &option,
                const QModelIndex &index) const override;
 
+    bool editorEvent(QEvent *event, QAbstractItemModel *model,
+                     const QStyleOptionViewItem &option, const QModelIndex &index) override;
+
+signals:
+    void cancelButtonClicked(const QModelIndex& index);
+
 private:
     static const int progressBarWidth = 150;
+    static const int cancelButtonWidth = 50;
 };
 
 } // namespace WidgetUi