previewwidget.cpp

   1 /*
   2  * Copyright © 2003-2007 Fredrik Höglund <fredrik@kde.org>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License version 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  16  * Boston, MA 02110-1301, USA.
  17  */
  18 #include <QDebug>
  19
  20 #include <QPainter>
  21 #include <QMouseEvent>
  22
  23 #include "previewwidget.h"
  24
  25 #include <X11/Xlib.h>
  26 #include <X11/Xcursor/Xcursor.h>
  27
  28 #include "crtheme.h"
  29
  30
  31 namespace {
  32   // Preview cursors
  33   const char *const cursorNames[] = {
  34     "left_ptr",
  35     "left_ptr_watch",
  36     "wait",
  37     "pointing_hand",
  38     "whats_this",
  39     "ibeam",
  40     "size_all",
  41     "size_fdiag",
  42     "cross",
  43     "split_h",
  44     "size_ver",
  45     "size_hor",
  46     "size_bdiag",
  47     "split_v",
  48   };
  49
  50   const int numCursors      = 9;     // The number of cursors from the above list to be previewed
  51   const int previewSize     = 24;    // The nominal cursor size to be used in the preview widget
  52   const int cursorSpacing   = 20;    // Spacing between preview cursors
  53   const int widgetMinWidth  = 10;    // The minimum width of the preview widget
  54   const int widgetMinHeight = 48;    // The minimum height of the preview widget
  55 }
  56
  57
  58 ///////////////////////////////////////////////////////////////////////////////
  59 class PreviewCursor {
  60 public:
  61   PreviewCursor (const XCursorTheme &theme, const QString &name);
  62   ~PreviewCursor () {}
  63
  64   const QPixmap &pixmap () const { return mPixmap; }
  65   Cursor handle () const { return mCursor.handle(); }
  66   int width () const { return mPixmap.width(); }
  67   int height () const { return mPixmap.height(); }
  68   inline QRect rect () const;
  69   void setPosition (const QPoint &p) { mPos = p; }
  70   void setPosition (int x, int y) { mPos = QPoint(x, y); }
  71   QPoint position () const { return mPos; }
  72   operator const QCursor& () const { return mCursor; }
  73   operator const QPixmap& () const { return pixmap(); }
  74
  75 private:
  76   QPixmap mPixmap;
  77   QCursor mCursor;
  78   QPoint mPos;
  79 };
  80
  81
  82 ///////////////////////////////////////////////////////////////////////////////
  83 PreviewCursor::PreviewCursor (const XCursorTheme &theme, const QString &name) {
  84   // Create the preview pixmap
  85   QImage image = theme.loadImage(name, previewSize);
  86   if (image.isNull()) return;
  87   int maxSize = previewSize*2;
  88   if (image.height() > maxSize || image.width() > maxSize)
  89     image = image.scaled(maxSize, maxSize, Qt::KeepAspectRatio, Qt::SmoothTransformation);
  90   mPixmap = QPixmap::fromImage(image);
  91   // load the cursor
  92   mCursor = theme.loadCursor(name, previewSize);
  93 }
  94
  95
  96 QRect PreviewCursor::rect () const {
  97   return QRect(mPos, mPixmap.size()).adjusted(-(cursorSpacing/2), -(cursorSpacing/2), cursorSpacing/2, cursorSpacing/2);
  98 }
  99
 100
 101 ///////////////////////////////////////////////////////////////////////////////
 102 PreviewWidget::PreviewWidget (QWidget *parent) : QWidget(parent) {
 103   setMouseTracking(true);
 104   current = NULL;
 105 }
 106
 107
 108 PreviewWidget::~PreviewWidget () {
 109   qDeleteAll(list);
 110   list.clear();
 111 }
 112
 113
 114 QSize PreviewWidget::sizeHint () const {
 115   int totalWidth = 0;
 116   int maxHeight = 0;
 117   foreach (const PreviewCursor *c, list) {
 118     totalWidth += c->width();
 119     maxHeight = qMax(c->height(), maxHeight);
 120   }
 121   totalWidth += (list.count()-1)*cursorSpacing;
 122   maxHeight = qMax(maxHeight, widgetMinHeight);
 123   return QSize(qMax(totalWidth, widgetMinWidth), qMax(height(), maxHeight));
 124 }
 125
 126
 127 void PreviewWidget::layoutItems () {
 128   if (!list.isEmpty()) {
 129     QSize size = sizeHint();
 130     int cursorWidth = size.width()/list.count();
 131     int nextX = (width()-size.width())/2;
 132     foreach (PreviewCursor *c, list) {
 133       c->setPosition(nextX+(cursorWidth-c->width())/2, (height()-c->height())/2);
 134       nextX += cursorWidth;
 135     }
 136   }
 137   needLayout = false;
 138 }
 139
 140
 141 void PreviewWidget::setTheme (const XCursorTheme &theme) {
 142   qDeleteAll(list);
 143   list.clear();
 144   for (int i = 0; i < numCursors; i++) list << new PreviewCursor(theme, cursorNames[i]);
 145   needLayout = true;
 146   updateGeometry();
 147   current = NULL;
 148   update();
 149 }
 150
 151
 152 void PreviewWidget::paintEvent (QPaintEvent *) {
 153   QPainter p(this);
 154   if (needLayout) layoutItems();
 155   foreach (const PreviewCursor *c, list) {
 156     if (c->pixmap().isNull()) continue;
 157     p.drawPixmap(c->position(), *c);
 158   }
 159 }
 160
 161
 162 void PreviewWidget::mouseMoveEvent (QMouseEvent *e) {
 163   if (needLayout) layoutItems();
 164   foreach (const PreviewCursor *c, list) {
 165     if (c->rect().contains(e->pos())) {
 166       if (c != current) {
 167         setCursor(*c);
 168         current = c;
 169       }
 170       return;
 171     }
 172   }
 173   setCursor(Qt::ArrowCursor);
 174   current = NULL;
 175 }
 176
 177
 178 void PreviewWidget::resizeEvent (QResizeEvent *) {
 179   if (!list.isEmpty()) needLayout = true;
 180 }