Make the album cover search results list scroll by pixel instead of item, and re-layout the items when any data changes

src/CMakeLists.txt

@@ -270,6 +270,7 @@ set(SOURCES
   widgets/fancytabwidget.cpp
   widgets/fileview.cpp
   widgets/fileviewlist.cpp
+  widgets/forcescrollperpixel.cpp
   widgets/freespacebar.cpp
   widgets/fullscreenhypnotoad.cpp
   widgets/groupediconview.cpp

src/ui/albumcovermanager.cpp

@@ -25,6 +25,7 @@
 #include "library/libraryquery.h"
 #include "library/sqlrow.h"
 #include "playlist/songmimedata.h"
+#include "widgets/forcescrollperpixel.h"
 #include "widgets/maclineedit.h"
 #include "ui/albumcoverchoicecontroller.h"
 
@@ -39,7 +40,6 @@
 #include <QMessageBox>
 #include <QPainter>
 #include <QProgressBar>
-#include <QScrollBar>
 #include <QSettings>
 #include <QShortcut>
 #include <QTimer>
@@ -49,7 +49,6 @@ const char* AlbumCoverManager::kSettingsGroup = "CoverManager";
 AlbumCoverManager::AlbumCoverManager(LibraryBackend* backend, QWidget* parent,
                                      QNetworkAccessManager* network)
   : QMainWindow(parent),
-    constructed_(false),
     ui_(new Ui_CoverManager),
     album_cover_choice_controller_(new AlbumCoverChoiceController(this)),
     backend_(backend),
@@ -188,7 +187,8 @@ void AlbumCoverManager::Init() {
   cover_loader_->Start(true);
   CoverLoaderInitialised();
   cover_searcher_->Init(cover_fetcher_);
-  constructed_ = true;
+
+  new ForceScrollPerPixel(ui_->albums, this);
 }
 
 void AlbumCoverManager::CoverLoaderInitialised() {
@@ -423,20 +423,6 @@ void AlbumCoverManager::UpdateStatusText() {
   }
 }
 
-bool AlbumCoverManager::event(QEvent* e) {
-  if (constructed_) {
-    // I think KDE styles override these, and ScrollPerItem is really confusing
-    // when you have huge items.
-    // We seem to have to reset them to sensible values each time the contents
-    // of ui_->albums changes.
-    ui_->albums->setVerticalScrollMode(QListWidget::ScrollPerPixel);
-    ui_->albums->verticalScrollBar()->setSingleStep(20);
-  }
-
-  QMainWindow::event(e);
-  return false;
-}
-
 bool AlbumCoverManager::eventFilter(QObject *obj, QEvent *event) {
   if (obj == ui_->albums && event->type() == QEvent::ContextMenu) {
     context_menu_items_ = ui_->albums->selectedItems();

src/ui/albumcovermanager.h

@@ -68,7 +68,6 @@ class AlbumCoverManager : public QMainWindow {
  protected:
   void showEvent(QShowEvent *);
   void closeEvent(QCloseEvent *);
-  bool event(QEvent *);
 
   // For the album view context menu events
   bool eventFilter(QObject *obj, QEvent *event);
@@ -139,8 +138,6 @@ class AlbumCoverManager : public QMainWindow {
   void SaveAndSetCover(QListWidgetItem* item, const QImage& image);
 
  private:
-  bool constructed_;
-
   Ui_CoverManager* ui_;
 
   AlbumCoverChoiceController* album_cover_choice_controller_;

src/ui/albumcoversearcher.cpp

@@ -20,6 +20,7 @@
 #include "core/logging.h"
 #include "covers/albumcoverfetcher.h"
 #include "covers/albumcoverloader.h"
+#include "widgets/forcescrollperpixel.h"
 #include "widgets/groupediconview.h"
 
 #include <QKeyEvent>
@@ -52,6 +53,8 @@ AlbumCoverSearcher::AlbumCoverSearcher(const QIcon& no_cover_icon, QWidget* pare
 
   connect(ui_->search, SIGNAL(clicked()), SLOT(Search()));
   connect(ui_->covers, SIGNAL(doubleClicked(QModelIndex)), SLOT(CoverDoubleClicked(QModelIndex)));
+
+  new ForceScrollPerPixel(ui_->covers, this);
 }
 
 AlbumCoverSearcher::~AlbumCoverSearcher() {

src/widgets/forcescrollperpixel.cpp

@@ -0,0 +1,39 @@
+/* This file is part of Clementine.
+   Copyright 2010, David Sansome <me@davidsansome.com>
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "forcescrollperpixel.h"
+
+#include <QAbstractItemView>
+#include <QEvent>
+#include <QScrollBar>
+
+
+ForceScrollPerPixel::ForceScrollPerPixel(QAbstractItemView* item_view, QObject* parent)
+  : QObject(parent),
+    item_view_(item_view)
+{
+  item_view_->installEventFilter(this);
+}
+
+bool ForceScrollPerPixel::eventFilter(QObject* object, QEvent* event) {
+  if (object == item_view_ && event->type() != QEvent::Destroy) {
+    item_view_->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
+    item_view_->verticalScrollBar()->setSingleStep(20);
+  }
+
+  return QObject::eventFilter(object, event);
+}

src/widgets/forcescrollperpixel.h

@@ -0,0 +1,38 @@
+/* This file is part of Clementine.
+   Copyright 2010, David Sansome <me@davidsansome.com>
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef FORCESCROLLPERPIXEL_H
+#define FORCESCROLLPERPIXEL_H
+
+#include <QObject>
+
+class QAbstractItemView;
+
+// Some KDE styles override the ScrollMode property of QAbstractItemViews.
+// This helper class forces the mode back to ScrollPerPixel.
+class ForceScrollPerPixel : public QObject {
+public:
+  ForceScrollPerPixel(QAbstractItemView* item_view, QObject* parent = 0);
+
+protected:
+  bool eventFilter(QObject* object, QEvent* event);
+
+private:
+  QAbstractItemView* item_view_;
+};
+
+#endif // FORCESCROLLPERPIXEL_H

src/widgets/groupediconview.cpp

@@ -98,6 +98,11 @@ void GroupedIconView::rowsInserted(const QModelIndex& parent, int start, int end
   LayoutItems();
 }
 
+void GroupedIconView::dataChanged(const QModelIndex& topLeft, const QModelIndex& bottomRight) {
+  QListView::dataChanged(topLeft, bottomRight);
+  LayoutItems();
+}
+
 void GroupedIconView::LayoutItems() {
   if (!model())
     return;

src/widgets/groupediconview.h

@@ -69,6 +69,7 @@ protected:
   void resizeEvent(QResizeEvent* e);
 
   // QAbstractItemView
+  void dataChanged(const QModelIndex& topLeft, const QModelIndex& bottomRight);
   QModelIndex indexAt(const QPoint& p) const;
   void rowsInserted(const QModelIndex& parent, int start, int end);
   void setSelection(const QRect& rect, QItemSelectionModel::SelectionFlags command);