Add an option to make columns in the playlist stretch to fit the window width like in Amarok 1. This option is enabled by default. Fixes issue #23

src/CMakeLists.txt

@@ -160,6 +160,7 @@ set(SOURCES
   widgets/sliderwidget.cpp
   widgets/spinbox.cpp
   widgets/stickyslider.cpp
+  widgets/stretchheaderview.cpp
   widgets/trackslider.cpp
   widgets/tracksliderslider.cpp
   widgets/lineedit.cpp
@@ -282,6 +283,7 @@ set(HEADERS
   widgets/sliderwidget.h
   widgets/spinbox.h
   widgets/stickyslider.h
+  widgets/stretchheaderview.h
   widgets/trackslider.h
   widgets/lineedit.h
 )

src/playlist/playlistheader.cpp

@@ -22,14 +22,19 @@
 #include <QSignalMapper>
 
 PlaylistHeader::PlaylistHeader(Qt::Orientation orientation, QWidget* parent)
-    : QHeaderView(orientation, parent),
+    : StretchHeaderView(orientation, parent),
       menu_(new QMenu(this)),
       show_mapper_(new QSignalMapper(this))
 {
   hide_action_ = menu_->addAction(tr("Hide..."), this, SLOT(HideCurrent()));
+  stretch_action_ = menu_->addAction(tr("Stretch columns to fit window"), this, SLOT(ToggleStretchEnabled()));
   menu_->addSeparator();
 
+  stretch_action_->setCheckable(true);
+  stretch_action_->setChecked(is_stretch_enabled());
+
   connect(show_mapper_, SIGNAL(mapped(int)), SLOT(ToggleVisible(int)));
+  connect(this, SIGNAL(StretchEnabledChanged(bool)), stretch_action_, SLOT(setChecked(bool)));
 }
 
 void PlaylistHeader::contextMenuEvent(QContextMenuEvent* e) {
@@ -69,15 +74,10 @@ void PlaylistHeader::HideCurrent() {
   if (menu_section_ == -1)
     return;
 
-  setSectionHidden(menu_section_, true);
+  SetSectionHidden(menu_section_, true);
 }
 
 void PlaylistHeader::ToggleVisible(int section) {
-  setSectionHidden(section, !isSectionHidden(section));
+  SetSectionHidden(section, !isSectionHidden(section));
   emit SectionVisibilityChanged(section, !isSectionHidden(section));
-
-  static const int kMinSectionSize = 80;
-
-  if (!isSectionHidden(section) && sectionSize(section) < kMinSectionSize)
-    resizeSection(section, kMinSectionSize);
 }

src/playlist/playlistheader.h

@@ -17,12 +17,12 @@
 #ifndef PLAYLISTHEADER_H
 #define PLAYLISTHEADER_H
 
-#include <QHeaderView>
+#include "widgets/stretchheaderview.h"
 
 class QMenu;
 class QSignalMapper;
 
-class PlaylistHeader : public QHeaderView {
+class PlaylistHeader : public StretchHeaderView {
   Q_OBJECT
 
  public:
@@ -45,6 +45,7 @@ class PlaylistHeader : public QHeaderView {
   int menu_section_;
   QMenu* menu_;
   QAction* hide_action_;
+  QAction* stretch_action_;
   QList<QAction*> show_actions_;
 
   QSignalMapper* show_mapper_;

src/playlist/playlistview.cpp

@@ -41,6 +41,7 @@ const int PlaylistView::kDropIndicatorGradientWidth = 5;
 PlaylistView::PlaylistView(QWidget *parent)
   : QTreeView(parent),
     playlist_(NULL),
+    header_(new PlaylistHeader(Qt::Horizontal, this)),
     glow_enabled_(true),
     currently_glowing_(false),
     glow_intensity_step_(0),
@@ -53,16 +54,17 @@ PlaylistView::PlaylistView(QWidget *parent)
     cached_current_row_row_(-1),
     drop_indicator_row_(-1)
 {
-  PlaylistHeader* header = new PlaylistHeader(Qt::Horizontal, this);
-  setHeader(header);
-  header->setMovable(true);
+  setHeader(header_);
+  header_->setMovable(true);
 
-  connect(header, SIGNAL(sectionResized(int,int,int)), SLOT(SaveGeometry()));
-  connect(header, SIGNAL(sectionMoved(int,int,int)), SLOT(SaveGeometry()));
-  connect(header, SIGNAL(SectionVisibilityChanged(int,bool)), SLOT(SaveGeometry()));
-  connect(header, SIGNAL(sectionResized(int,int,int)), SLOT(InvalidateCachedCurrentPixmap()));
-  connect(header, SIGNAL(sectionMoved(int,int,int)), SLOT(InvalidateCachedCurrentPixmap()));
-  connect(header, SIGNAL(SectionVisibilityChanged(int,bool)), SLOT(InvalidateCachedCurrentPixmap()));
+  connect(header_, SIGNAL(sectionResized(int,int,int)), SLOT(SaveGeometry()));
+  connect(header_, SIGNAL(sectionMoved(int,int,int)), SLOT(SaveGeometry()));
+  connect(header_, SIGNAL(SectionVisibilityChanged(int,bool)), SLOT(SaveGeometry()));
+  connect(header_, SIGNAL(sectionResized(int,int,int)), SLOT(InvalidateCachedCurrentPixmap()));
+  connect(header_, SIGNAL(sectionMoved(int,int,int)), SLOT(InvalidateCachedCurrentPixmap()));
+  connect(header_, SIGNAL(SectionVisibilityChanged(int,bool)), SLOT(InvalidateCachedCurrentPixmap()));
+  connect(header_, SIGNAL(StretchEnabledChanged(bool)), SLOT(SaveSettings()));
+  connect(header_, SIGNAL(StretchEnabledChanged(bool)), SLOT(StretchChanged(bool)));
 
   inhibit_autoscroll_timer_->setInterval(kAutoscrollGraceTimeout * 1000);
   inhibit_autoscroll_timer_->setSingleShot(true);
@@ -123,34 +125,28 @@ void PlaylistView::LoadGeometry() {
   QSettings settings;
   settings.beginGroup(kSettingsGroup);
 
-  if (!header()->restoreState(settings.value("state").toByteArray())) {
-    header()->hideSection(Playlist::Column_Disc);
-    header()->hideSection(Playlist::Column_Year);
-    header()->hideSection(Playlist::Column_Genre);
-    header()->hideSection(Playlist::Column_BPM);
-    header()->hideSection(Playlist::Column_Bitrate);
-    header()->hideSection(Playlist::Column_Samplerate);
-    header()->hideSection(Playlist::Column_Filename);
-    header()->hideSection(Playlist::Column_BaseFilename);
-    header()->hideSection(Playlist::Column_Filesize);
-    header()->hideSection(Playlist::Column_Filetype);
-    header()->hideSection(Playlist::Column_DateCreated);
-    header()->hideSection(Playlist::Column_DateModified);
-    header()->hideSection(Playlist::Column_AlbumArtist);
-    header()->hideSection(Playlist::Column_Composer);
-  }
-
-  // Work around weirdness in QHeaderView
-  for (int i=0 ; i<header()->count() ; ++i) {
-    if (header()->sectionSize(i) == 0)
-      header()->hideSection(i);
+  if (!header_->restoreState(settings.value("state").toByteArray())) {
+    header_->HideSection(Playlist::Column_Disc);
+    header_->HideSection(Playlist::Column_Year);
+    header_->HideSection(Playlist::Column_Genre);
+    header_->HideSection(Playlist::Column_BPM);
+    header_->HideSection(Playlist::Column_Bitrate);
+    header_->HideSection(Playlist::Column_Samplerate);
+    header_->HideSection(Playlist::Column_Filename);
+    header_->HideSection(Playlist::Column_BaseFilename);
+    header_->HideSection(Playlist::Column_Filesize);
+    header_->HideSection(Playlist::Column_Filetype);
+    header_->HideSection(Playlist::Column_DateCreated);
+    header_->HideSection(Playlist::Column_DateModified);
+    header_->HideSection(Playlist::Column_AlbumArtist);
+    header_->HideSection(Playlist::Column_Composer);
   }
 }
 
 void PlaylistView::SaveGeometry() {
   QSettings settings;
   settings.beginGroup(kSettingsGroup);
-  settings.setValue("state", header()->saveState());
+  settings.setValue("state", header_->saveState());
 }
 
 void PlaylistView::ReloadBarPixmaps() {
@@ -563,9 +559,21 @@ void PlaylistView::ReloadSettings() {
   QSettings s;
   s.beginGroup(kSettingsGroup);
   glow_enabled_ = s.value("glow_effect", true).toBool();
+  header_->SetStretchEnabled(s.value("stretch", true).toBool());
 
   if (currently_glowing_ && glow_enabled_ && isVisible())
     StartGlowing();
   if (!glow_enabled_)
     StopGlowing();
 }
+
+void PlaylistView::SaveSettings() {
+  QSettings s;
+  s.beginGroup(kSettingsGroup);
+  s.setValue("glow_effect", glow_enabled_);
+  s.setValue("stretch", header_->is_stretch_enabled());
+}
+
+void PlaylistView::StretchChanged(bool stretch) {
+  setHorizontalScrollBarPolicy(stretch ? Qt::ScrollBarAlwaysOff : Qt::ScrollBarAsNeeded);
+}

src/playlist/playlistview.h

@@ -22,8 +22,9 @@
 #include <QTreeView>
 #include <QBasicTimer>
 
-class RadioLoadingIndicator;
 class LibraryBackend;
+class PlaylistHeader;
+class RadioLoadingIndicator;
 
 class PlaylistView : public QTreeView {
   Q_OBJECT
@@ -77,6 +78,9 @@ class PlaylistView : public QTreeView {
   void InvalidateCachedCurrentPixmap();
   void PlaylistDestroyed();
 
+  void SaveSettings();
+  void StretchChanged(bool stretch);
+
  private:
   void ReloadBarPixmaps();
   QList<QPixmap> LoadBarPixmap(const QString& filename);
@@ -94,6 +98,7 @@ class PlaylistView : public QTreeView {
   QModelIndex PrevEditableIndex(const QModelIndex& current);
 
   Playlist* playlist_;
+  PlaylistHeader* header_;
 
   bool glow_enabled_;
   bool currently_glowing_;

src/translations/ar.po

@@ -1587,6 +1587,9 @@ msgstr "المجرى"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/bg.po

@@ -1587,6 +1587,9 @@ msgstr ""
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/ca.po

@@ -1608,6 +1608,9 @@ msgstr "Flux de dades"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/cs.po

@@ -1591,6 +1591,9 @@ msgstr "Proud"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/da.po

@@ -1594,6 +1594,9 @@ msgstr "Stream"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/de.po

@@ -1608,6 +1608,9 @@ msgstr "Stream"
 msgid "Streaming membership"
 msgstr "Streamingmitgliedschaft"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "%1 erfolgreich geschrieben"

src/translations/el.po

@@ -1609,6 +1609,9 @@ msgstr "Stream"
 msgid "Streaming membership"
 msgstr "Συνδρομή ροής"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Επιτυχία εγγραφής του %1"

src/translations/en_CA.po

@@ -1592,6 +1592,9 @@ msgstr "Stream"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Successfully written %1"

src/translations/en_GB.po

@@ -1589,6 +1589,9 @@ msgstr "Stream"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/es.po

@@ -1612,6 +1612,9 @@ msgstr "Transmisión"
 msgid "Streaming membership"
 msgstr "Membrecía de streaming"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "%1 se ha escrito con éxito"

src/translations/fi.po

@@ -1589,6 +1589,9 @@ msgstr "Virta"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/fr.po

@@ -1601,6 +1601,9 @@ msgstr "Flux"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/gl.po

@@ -1589,6 +1589,9 @@ msgstr "Fluxo"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/hu.po

@@ -1604,6 +1604,9 @@ msgstr "Adatfolyam"
 msgid "Streaming membership"
 msgstr "Adatfolyam tagság"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "%1 sikeresen írva"

src/translations/it.po

@@ -1616,6 +1616,9 @@ msgstr "Flusso"
 msgid "Streaming membership"
 msgstr "Trasmissione"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "%1 scritto correttamente"

src/translations/kk.po

@@ -1589,6 +1589,9 @@ msgstr "Ағындық"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/lt.po

@@ -1587,6 +1587,9 @@ msgstr ""
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/nb.po

@@ -1590,6 +1590,9 @@ msgstr "Strøm"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/nl.po

@@ -1606,6 +1606,9 @@ msgstr "Radiostream"
 msgid "Streaming membership"
 msgstr "Streaming lidmaatschap"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "%1 met succes weggeschreven"

src/translations/oc.po

@@ -1587,6 +1587,9 @@ msgstr "Flux"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/pl.po

@@ -1598,6 +1598,9 @@ msgstr "Strumień"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/pt.po

@@ -1604,6 +1604,9 @@ msgstr "Emissão"
 msgid "Streaming membership"
 msgstr "Emissão"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Escrito com sucesso %1"

src/translations/pt_BR.po

@@ -1599,6 +1599,9 @@ msgstr "Transmissão online"
 msgid "Streaming membership"
 msgstr "Membro de multimídia"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "%1 gravado com sucesso"

src/translations/ro.po

@@ -1588,6 +1588,9 @@ msgstr "Flux"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/ru.po

@@ -1601,6 +1601,9 @@ msgstr "Поток"
 msgid "Streaming membership"
 msgstr "Streaming подписка"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Успешно записано %1"

src/translations/sk.po

@@ -1602,6 +1602,9 @@ msgstr "Stream"
 msgid "Streaming membership"
 msgstr "Streamovacie členstvo"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Úspešne zapísané %1"

src/translations/sl.po

@@ -1604,6 +1604,9 @@ msgstr "Tok"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Uspešno zapisan %1"

src/translations/sr.po

@@ -1592,6 +1592,9 @@ msgstr "Ток"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/sv.po

@@ -1596,6 +1596,9 @@ msgstr "Ström"
 msgid "Streaming membership"
 msgstr "Strömmningsmedlemskap"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Skrev %1 med lyckat resultat"

src/translations/tr.po

@@ -1593,6 +1593,9 @@ msgstr "Akış"
 msgid "Streaming membership"
 msgstr "Yayın akış üyeliği"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/translations.pot

@@ -1577,6 +1577,9 @@ msgstr ""
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/uk.po

@@ -1602,6 +1602,9 @@ msgstr "Потік"
 msgid "Streaming membership"
 msgstr "Потокове членство"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr "Успішно записано %1"

src/translations/zh_CN.po

@@ -1587,6 +1587,9 @@ msgstr "流媒体"
 msgid "Streaming membership"
 msgstr ""
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/translations/zh_TW.po

@@ -1592,6 +1592,9 @@ msgstr "串流"
 msgid "Streaming membership"
 msgstr "流媒體成員"
 
+msgid "Stretch columns to fit window"
+msgstr ""
+
 #, qt-format
 msgid "Successfully written %1"
 msgstr ""

src/widgets/stretchheaderview.cpp

@@ -0,0 +1,204 @@
+/* This file is part of Clementine.
+
+   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 "stretchheaderview.h"
+
+#include <QDataStream>
+#include <QtDebug>
+
+#include <algorithm>
+
+const float StretchHeaderView::kMinimumColumnWidth = 0.01;
+
+StretchHeaderView::StretchHeaderView(Qt::Orientation orientation, QWidget* parent)
+  : QHeaderView(orientation, parent),
+    stretch_enabled_(false),
+    in_mouse_move_event_(false)
+{
+  connect(this, SIGNAL(sectionResized(int,int,int)), SLOT(SectionResized(int,int,int)));
+}
+
+void StretchHeaderView::setModel(QAbstractItemModel* model) {
+  QHeaderView::setModel(model);
+
+  if (stretch_enabled_) {
+    column_widths_.clear();
+    int count = model->columnCount();
+    for (int i=0 ; i<count ; ++i) {
+      column_widths_ << 1.0 / count;
+    }
+  }
+}
+
+void StretchHeaderView::NormaliseWidths() {
+  if (!stretch_enabled_)
+    return;
+
+  float sum = 0.0;
+  foreach (float width, column_widths_)
+    sum += width;
+
+  if (sum != 0.0 && !qFuzzyCompare(sum, 1.0f)) {
+    const float mult = 1.0 / sum;
+    for (int i=0 ; i<column_widths_.count() ; ++i) {
+      column_widths_[i] *= mult;
+    }
+  }
+}
+
+void StretchHeaderView::UpdateWidths(const QList<int>& sections) {
+  if (!stretch_enabled_)
+    return;
+
+  int total_pixels = 0;
+  for (int i=0 ; i<column_widths_.count() ; ++i) {
+    const float w = column_widths_[i];
+    const int pixels = w * width();
+    total_pixels += pixels;
+
+    if (!sections.isEmpty() && !sections.contains(i))
+      continue;
+
+    if (pixels == 0 && !isSectionHidden(i))
+      hideSection(i);
+    else if (pixels != 0 && isSectionHidden(i))
+      showSection(i);
+
+    if (pixels != 0)
+      resizeSection(i, pixels);
+  }
+
+  // Add the remaining pixels to some arbitrary column just to make sure it
+  // adds up to the total width.
+  for (int i=0 ; i<column_widths_.count() ; ++i) {
+    if (!sections.isEmpty() && !sections.contains(i))
+      continue;
+
+    const float w = column_widths_[i];
+    const int pixels = w * width();
+    if (pixels != 0) {
+      resizeSection(i, pixels + (width() - total_pixels));
+      break;
+    }
+  }
+}
+
+void StretchHeaderView::HideSection(int logical) {
+  if (!stretch_enabled_) {
+    hideSection(logical);
+    return;
+  }
+
+  column_widths_[logical] = 0.0;
+  NormaliseWidths();
+  UpdateWidths();
+}
+
+void StretchHeaderView::ShowSection(int logical) {
+  if (!stretch_enabled_) {
+    showSection(logical);
+    return;
+  }
+
+  // How many sections are visible already?
+  int visible_count = 0;
+  for (int i=0 ; i<count() ; ++i) {
+    if (!isSectionHidden(i))
+      visible_count ++;
+  }
+
+  column_widths_[logical] =
+      visible_count == 0 ? 1.0 : 1.0 / visible_count;
+  NormaliseWidths();
+  UpdateWidths();
+}
+
+void StretchHeaderView::SetSectionHidden(int logical, bool hidden) {
+  hidden ? HideSection(logical) : ShowSection(logical);
+}
+
+void StretchHeaderView::resizeEvent(QResizeEvent* event) {
+  QHeaderView::resizeEvent(event);
+
+  if (!stretch_enabled_)
+    return;
+
+  UpdateWidths();
+}
+
+void StretchHeaderView::mouseMoveEvent(QMouseEvent* e) {
+  in_mouse_move_event_ = true;
+  QHeaderView::mouseMoveEvent(e);
+  in_mouse_move_event_ = false;
+}
+
+void StretchHeaderView::SectionResized(int logical, int, int new_size) {
+  if (!stretch_enabled_)
+    return;
+
+  if (in_mouse_move_event_) {
+    // Update this section's proportional width
+    column_widths_[logical] = float(new_size) / width();
+
+    // Find the visible sections to the right of the section that's being resized
+    int visual = visualIndex(logical);
+    QList<int> logical_sections_to_resize;
+    for (int i=0 ; i<count() ; ++i) {
+      if (!isSectionHidden(i) && visualIndex(i) > visual)
+        logical_sections_to_resize << i;
+    }
+
+    // Resize just those columns
+    if (!logical_sections_to_resize.isEmpty()) {
+      float sum = 0.0;
+      foreach (float width, column_widths_)
+        sum += width;
+
+      if (sum != 0.0 && !qFuzzyCompare(sum, 1.0f)) {
+        const float d = (1.0 - sum) / logical_sections_to_resize.count();
+        foreach (int i, logical_sections_to_resize) {
+          column_widths_[i] = qMax(kMinimumColumnWidth, column_widths_[i] + d);
+        }
+      }
+
+      in_mouse_move_event_ = false;
+      UpdateWidths(logical_sections_to_resize);
+      in_mouse_move_event_ = true;
+    }
+  }
+}
+
+void StretchHeaderView::ToggleStretchEnabled() {
+  SetStretchEnabled(!is_stretch_enabled());
+}
+
+void StretchHeaderView::SetStretchEnabled(bool enabled) {
+  stretch_enabled_ = enabled;
+
+  if (enabled) {
+    // Initialise the list of widths from the current state of the widget
+    column_widths_.clear();
+    for (int i=0 ; i<count() ; ++i) {
+      column_widths_ << float(sectionSize(i)) / width();
+    }
+
+    // Stretch the columns to fill the widget
+    NormaliseWidths();
+    UpdateWidths();
+  }
+
+  emit StretchEnabledChanged(enabled);
+}

src/widgets/stretchheaderview.h

@@ -0,0 +1,63 @@
+/* This file is part of Clementine.
+
+   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 STRETCHHEADERVIEW_H
+#define STRETCHHEADERVIEW_H
+
+#include <QHeaderView>
+
+class StretchHeaderView : public QHeaderView {
+  Q_OBJECT
+
+public:
+  StretchHeaderView(Qt::Orientation orientation, QWidget* parent = 0);
+
+  static const float kMinimumColumnWidth;
+
+  void setModel(QAbstractItemModel* model);
+
+  void HideSection(int logical);
+  void ShowSection(int logical);
+  void SetSectionHidden(int logical, bool hidden);
+
+  bool is_stretch_enabled() const { return stretch_enabled_; }
+
+public slots:
+  void ToggleStretchEnabled();
+  void SetStretchEnabled(bool enabled);
+
+signals:
+  void StretchEnabledChanged(bool enabled);
+
+protected:
+  void mouseMoveEvent(QMouseEvent* e);
+  void resizeEvent(QResizeEvent* event);
+
+private:
+  void NormaliseWidths();
+  void UpdateWidths(const QList<int>& sections = QList<int>());
+
+private slots:
+  void SectionResized(int logical, int old_size, int new_size);
+
+private:
+  bool stretch_enabled_;
+  QList<float> column_widths_;
+
+  bool in_mouse_move_event_;
+};
+
+#endif // STRETCHHEADERVIEW_H