kdbg/tableview.cpp

   1 // $Id$
   2
   3 // Copyright by Johannes Sixt
   4 // This file is under GPL, the GNU General Public Licence
   5
   6 #include "tableview.h"
   7
   8 #include <qapplication.h>
   9 #include <qpainter.h>
  10 #include <qscrollbar.h>
  11
  12 #if 0
  13 class CornerSquare : public QWidget     // internal class
  14 {
  15 public:
  16     CornerSquare(QWidget* parent, const char* name = 0);
  17     void paintEvent(QPaintEvent*);
  18 };
  19
  20 CornerSquare::CornerSquare(QWidget* parent, const char* name) :
  21         QWidget(parent, name)
  22 {
  23 }
  24
  25 void CornerSquare::paintEvent(QPaintEvent*)
  26 {
  27 }
  28 #endif
  29
  30 /*
  31  * A simplified version of QTableView, which works only for rows of uniform
  32  * height: cellHeight() is only invoked for row 0.
  33  */
  34 TableView::TableView(QWidget* parent, const char* name, WFlags f) :
  35         QWidget(parent, name, f),
  36         m_numRows(0),
  37         m_numCols(0),
  38         m_xOffset(0),
  39         m_yOffset(0),
  40         m_totalSize(0, 0),
  41         m_autoUpdate(true)
  42 {
  43     m_sbV = new QScrollBar(QScrollBar::Vertical, this, "table_sbV");
  44     m_sbH = new QScrollBar(QScrollBar::Horizontal, this, "table_sbH");
  45     m_sbV->resize(m_sbV->sizeHint());
  46     m_sbH->resize(m_sbH->sizeHint());
  47     m_sbV->hide();
  48     m_sbH->hide();
  49     connect(m_sbV, SIGNAL(valueChanged(int)), this, SLOT(sbVer(int)));
  50     connect(m_sbH, SIGNAL(valueChanged(int)), this, SLOT(sbHor(int)));
  51
  52     m_sbCorner = new QWidget(this, "table_corner");
  53     m_sbCorner->hide();
  54
  55     setFocusPolicy(WheelFocus);
  56 }
  57
  58 TableView::~TableView()
  59 {
  60 }
  61
  62 void TableView::setNumCols(int cols)
  63 {
  64     m_numCols = cols;
  65 }
  66
  67 void TableView::setNumRows(int rows)
  68 {
  69     m_numRows = rows;
  70 }
  71
  72 void TableView::updateTableSize()
  73 {
  74     // don't call cellHeight if there are now rows
  75     m_totalSize.setHeight(m_numRows > 0 ? cellHeight(0) * m_numRows : 0);
  76     int w = 0;
  77     for (int i = 0; i < m_numCols; i++) {
  78         w += cellWidth(i);
  79     }
  80     m_totalSize.setWidth(w);
  81     int maxX = maxXOffset();
  82     int maxY = maxYOffset();
  83     if (xOffset() > maxX || yOffset() > maxY) {
  84         setOffset(QMIN(xOffset(),maxX), QMIN(yOffset(),maxY));
  85     } else {
  86         updateScrollBars();
  87     }
  88 }
  89
  90 int TableView::lastRowVisible() const
  91 {
  92     if (numRows() == 0)
  93         return -1;
  94     int r = (viewHeight() + m_yOffset) / cellHeight(0) - 1;
  95     if (r < 0) {
  96         return 0;
  97     } else if (r >= numRows()) {
  98         return numRows()-1;
  99     } else {
 100         return r;
 101     }
 102 }
 103
 104 int TableView::maxXOffset() const
 105 {
 106     int o = m_totalSize.width()-viewWidth();
 107     return QMAX(0, o);
 108 }
 109
 110 int TableView::maxYOffset() const
 111 {
 112     int o = m_totalSize.height()-viewHeight();
 113     return QMAX(0, o);
 114 }
 115
 116 void TableView::setOffset(int x, int y)
 117 {
 118     int oldX = m_xOffset;
 119     int oldY = m_yOffset;
 120     int maxX = maxXOffset();
 121     int maxY = maxYOffset();
 122     m_xOffset = QMIN(x, maxX);
 123     m_yOffset = QMIN(y, maxY);
 124     if (m_autoUpdate) {
 125         QRect r(0,0, viewWidth(), viewHeight());
 126         scroll(oldX-m_xOffset, oldY-m_yOffset, r);
 127     }
 128     updateScrollBars();
 129 }
 130
 131 void TableView::setTopCell(int row)
 132 {
 133     if (numRows() > 0)
 134         setYOffset(row * cellHeight(0));
 135 }
 136
 137 int TableView::topCell() const
 138 {
 139     if (numRows() > 0)
 140         return yOffset() / cellHeight(0);
 141     else
 142         return -1;
 143 }
 144
 145 int TableView::leftCell() const
 146 {
 147     int x = -xOffset();
 148     int c = 0;
 149     while (x < 0) {
 150         x += cellWidth(c);
 151         c++;
 152     }
 153     // special-casing x == 0 saves one call to cellWidth()
 154     return x == 0  ?  c  :  c-1;
 155 }
 156
 157 int TableView::viewWidth() const
 158 {
 159     // takes into account whether scrollbars are visible
 160     int w = width();
 161     if (m_sbV->isVisible())
 162         w -= m_sbV->width();
 163     return w;
 164 }
 165
 166 int TableView::viewHeight() const
 167 {
 168     // takes into account whether scrollbars are visible
 169     int h = height();
 170     if (m_sbH->isVisible())
 171         h -= m_sbH->height();
 172     return h;
 173 }
 174
 175 bool TableView::rowIsVisible(int row) const
 176 {
 177     return row >= topCell() && row <= lastRowVisible();
 178 }
 179
 180 int TableView::findRow(int y) const
 181 {
 182     if (numRows() == 0)
 183         return -1;
 184     int r = (yOffset() + y) / cellHeight(0);
 185     if (r < 0 || r >= numRows())
 186         return -1;
 187     else
 188         return r;
 189 }
 190
 191 bool TableView::rowYPos(int row, int* top) const
 192 {
 193     if (numRows() == 0)
 194         return false;           // now rows => nothing visible
 195     int y = row * cellHeight(0) - yOffset();
 196     if (y <= -cellHeight(0))
 197         return false;           // row is above view
 198     if (y > viewHeight())
 199         return false;           // row is below view
 200     *top = y;
 201     return true;
 202 }
 203
 204 int TableView::findCol(int x) const
 205 {
 206     x += xOffset();
 207     if (x < 0)
 208         return -1;
 209     for (int col = 0; col < numCols(); col++) {
 210         x -= cellWidth(col);
 211         if (x < 0)
 212             return col;
 213     }
 214     return -1;
 215 }
 216
 217 bool TableView::colXPos(int col, int* left) const
 218 {
 219     int x = -xOffset();
 220     int viewW = viewWidth();
 221     int c = 0;
 222     while (c < col) {
 223         x += cellWidth(c);
 224         if (x >= viewW) {
 225             // col is completely to the right of view
 226             return false;
 227         }
 228         c++;
 229     }
 230     if (x <= 0) {
 231         if (x + cellWidth(col) > 0) {
 232             // col is partially visible at left of view
 233             *left = x;
 234             return true;
 235         } else {
 236             // col is completely to the left of view
 237             return false;
 238         }
 239     } else {
 240         // left edge of col is in the view
 241         *left = x;
 242         return true;
 243     }
 244 }
 245
 246 void TableView::updateCell(int row, int col, bool erase)
 247 {
 248     int x, y;
 249     if (!colXPos(col, &x))
 250         return;
 251     if (!rowYPos(row, &y))
 252         return;
 253     QRect r(x, y, cellWidth(col), cellHeight(0/*row*/));
 254     repaint(r, erase);
 255 }
 256
 257 void TableView::setupPainter(QPainter* /*p*/)
 258 {
 259     // does nothing special
 260 }
 261
 262 void TableView::resizeEvent(QResizeEvent* /*ev*/)
 263 {
 264     updateScrollBars();
 265 }
 266
 267 void TableView::paintEvent(QPaintEvent* /*ev*/)
 268 {
 269     if (numRows() == 0 || numCols() == 0)
 270         return;
 271
 272     QPainter p(this);
 273     setupPainter(&p);
 274
 275     int viewH = viewHeight();
 276     int viewW = viewWidth();
 277     int leftCol = leftCell();
 278     int leftX = 0;
 279     colXPos(leftCol, &leftX);
 280     int row = topCell();
 281     int y = 0;
 282     rowYPos(row, &y);
 283     QWMatrix matrix;
 284     while (y < viewH && row < numRows()) {
 285         int col = leftCol;
 286         int x = leftX;
 287         while (x < viewW && col < numCols()) {
 288             matrix.translate(x, y);
 289             p.setWorldMatrix(matrix);
 290             paintCell(&p, row, col);
 291             matrix.reset();
 292             p.setWorldMatrix(matrix);
 293             x += cellWidth(col);
 294             col++;
 295         }
 296         row++;
 297         y += cellHeight(0/*row*/);
 298     }
 299 }
 300
 301 void TableView::wheelEvent(QWheelEvent* ev)
 302 {
 303 #if QT_VERSION >= 300
 304     if (ev->orientation() == Horizontal && m_sbH != 0)
 305     {
 306         QApplication::sendEvent(m_sbH, ev);
 307     }
 308     else
 309 #endif
 310     {
 311         if (m_sbV != 0)
 312         {
 313             QApplication::sendEvent(m_sbV, ev);
 314         }
 315     }
 316 }
 317
 318 void TableView::updateScrollBars()
 319 {
 320     // see which scrollbars we absolutely need
 321     int w = width();
 322     int h = height();
 323     bool needV = m_totalSize.height() > h;
 324     bool needH = m_totalSize.width() > w;
 325
 326     // if we need neither, remove the scrollbars and we're done
 327     if (!needV && !needH)
 328     {
 329         m_sbH->hide();
 330         m_sbV->hide();
 331         m_sbCorner->hide();
 332         return;
 333     }
 334     // if we need both, reduce view
 335     if (needV && needH) {
 336         w -= m_sbV->width();
 337         h -= m_sbH->height();
 338     } else {
 339         /*
 340          * If we need the vertical bar, but not the horizontal, the
 341          * presence of the vertical bar might reduce the space so that we
 342          * also need the horizontal bar. Likewise, if we need the
 343          * horizontal but not necessarily the vertical bar.
 344          */
 345         if (needV) {
 346             w -= m_sbV->width();
 347             if (w < 0)
 348                 w = 0;
 349             needH = m_totalSize.width() > w;
 350             if (needH) {
 351                 h -= m_sbH->height();
 352             }
 353         } else {
 354             // assert(needH)
 355             h -= m_sbH->height();
 356             if (h < 0)
 357                 h = 0;
 358             needV = m_totalSize.height() > h;
 359             if (needV) {
 360                 w -= m_sbV->width();
 361             }
 362         }
 363     }
 364     // set scrollbars
 365     // note: must show() early because max?Offset() depends on visibility
 366     if (needH) {
 367         m_sbH->setGeometry(0, h, w, m_sbH->height());
 368         m_sbH->show();
 369         m_sbH->setRange(0, maxXOffset());
 370         m_sbH->setValue(xOffset());
 371         m_sbH->setSteps(32, w);
 372     } else {
 373         m_sbH->hide();
 374     }
 375     if (needV) {
 376         m_sbV->setGeometry(w, 0, m_sbV->width(), h);
 377         m_sbV->show();
 378         m_sbV->setRange(0, maxYOffset());
 379         m_sbV->setValue(yOffset());
 380         m_sbV->setSteps(cellHeight(0), h);
 381     } else {
 382         m_sbV->hide();
 383     }
 384     // corner square: only if both scrollbars are there
 385     if (needH && needV) {
 386         m_sbCorner->setGeometry(w, h, m_sbV->width(), m_sbH->height());
 387         m_sbCorner->show();
 388     } else {
 389         m_sbCorner->hide();
 390     }
 391 }
 392
 393 void TableView::sbVer(int value)
 394 {
 395     setYOffset(value);
 396 }
 397
 398 void TableView::sbHor(int value)
 399 {
 400     setXOffset(value);
 401 }
 402
 403 #include "tableview.moc"