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