Initial commit.

src/widgets/stretchheaderview.h

@@ -0,0 +1,96 @@
+/*
+ * Strawberry Music Player
+ * This file was part of Clementine.
+ * Copyright 2010, David Sansome <me@davidsansome.com>
+ *
+ * Strawberry 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.
+ *
+ * Strawberry 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 Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ */
+
+#ifndef STRETCHHEADERVIEW_H
+#define STRETCHHEADERVIEW_H
+
+#include "config.h"
+
+#include <QHeaderView>
+
+class StretchHeaderView : public QHeaderView {
+  Q_OBJECT
+
+ public:
+  StretchHeaderView(Qt::Orientation orientation, QWidget* parent = nullptr);
+
+  typedef double ColumnWidthType;
+
+  static const int kMinimumColumnWidth;
+  static const int kMagicNumber;
+
+  void setModel(QAbstractItemModel* model);
+
+  // Serialises the proportional and actual column widths.  Use these instead
+  // of QHeaderView::restoreState and QHeaderView::saveState to persist the
+  // proportional values directly and avoid floating point errors over time.
+  bool RestoreState(const QByteArray& data);
+  QByteArray SaveState() const;
+
+  // Hides a section and resizes all other sections to fill the gap.  Does
+  // nothing if you try to hide the last section.
+  void HideSection(int logical);
+
+  // Shows a section and resizes all other sections to make room.
+  void ShowSection(int logical);
+
+  // Calls either HideSection or ShowSection.
+  void SetSectionHidden(int logical, bool hidden);
+
+  // Sets the width of the given column and resizes other columns appropriately.
+  // width is the proportion of the entire width from 0.0 to 1.0.
+  void SetColumnWidth(int logical, ColumnWidthType width);
+
+  bool is_stretch_enabled() const { return stretch_enabled_; }
+
+public slots:
+  // Changes the stretch mode.  Enabling stretch mode will initialise the
+  // proportional column widths from the current state of the header.
+  void ToggleStretchEnabled();
+  void SetStretchEnabled(bool enabled);
+
+signals:
+  // Emitted when the stretch mode is changed.
+  void StretchEnabledChanged(bool enabled);
+
+protected:
+  // QWidget
+  void mouseMoveEvent(QMouseEvent* e);
+  void resizeEvent(QResizeEvent* event);
+
+ private:
+  // Scales column_widths_ values so the total is 1.0.
+  void NormaliseWidths(const QList<int>& sections = QList<int>());
+
+  // Resizes the actual columns to make them match the proportional values
+  // in column_widths_.
+  void UpdateWidths(const QList<int>& sections = QList<int>());
+
+private slots:
+  void SectionResized(int logical, int old_size, int new_size);
+
+private:
+  bool stretch_enabled_;
+  QVector<ColumnWidthType> column_widths_;
+
+  bool in_mouse_move_event_;
+};
+
+#endif  // STRETCHHEADERVIEW_H