Qt: Defer proto tree column content resizing.

Try to avoid the following call graph:

ProtoTree::expandAll
  ...
    ProtoTree::expand
      ...
        QTreeView::resizeColumnToContents

QTreeView::resizeColumnToContents calls sizeHintForColumn, which
iterates over a number of items (default 1000). Calling it from
ProtoTree::expand can lead to excessive wheel-spinning.

Add a single-shot timer for resizeColumnToContents. This is similar to
what QTreeView does internally when columns are resized.

Bug: 12228
Change-Id: I7b50c1486b3a25817efae58efbb8c9e961dbdab0
Reviewed-on: https://code.wireshark.org/review/14411
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Gerald Combs <gerald@wireshark.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/ui/qt/proto_tree.h b/ui/qt/proto_tree.h
index a97f69c6a5..56815cc85d 100644
--- a/ui/qt/proto_tree.h
+++ b/ui/qt/proto_tree.h
@@ -47,7 +47,9 @@ public:
     void clear();
 
 protected:
-     void contextMenuEvent(QContextMenuEvent *event);
+    virtual void contextMenuEvent(QContextMenuEvent *event);
+    virtual void timerEvent(QTimerEvent *event);
+    virtual void keyReleaseEvent(QKeyEvent *event);
 
 private:
     QMenu ctx_menu_;
@@ -57,6 +59,7 @@ private:
     QAction *decode_as_;
     QList<QAction *> copy_actions_;
     QFont mono_font_;
+    int column_resize_timer_;
 
 signals:
     void protoItemSelected(const QString &);
@@ -76,6 +79,9 @@ public slots:
     void expandAll();
     void collapseAll();
     void itemDoubleClick(QTreeWidgetItem *item, int column);
+
+private slots:
+    void updateContentWidth();
 };
 
 #endif // PROTO_TREE_H