+}
+
+void ChatScene::rowsInserted(const QModelIndex &index, int start, int end) {
+ Q_UNUSED(index);
+ qreal h = 0;
+ qreal y = _sceneRect.y();
+ qreal width = _sceneRect.width();
+ bool atTop = true;
+ bool atBottom = false;
+ bool moveTop = false;
+
+ if(start > 0) {
+ y = _lines.value(start - 1)->y() + _lines.value(start - 1)->height();
+ atTop = false;
+ }
+ if(start == _lines.count())
+ atBottom = true;
+
+ qreal contentsWidth = width - secondColumnHandle()->sceneRight();
+ qreal senderWidth = secondColumnHandle()->sceneLeft() - firstColumnHandle()->sceneRight();
+ qreal timestampWidth = firstColumnHandle()->sceneLeft();
+ QPointF contentsPos(secondColumnHandle()->sceneRight(), 0);
+ QPointF senderPos(firstColumnHandle()->sceneRight(), 0);
+
+
+ for(int i = end; i >= start; i--) {
+ ChatLine *line = new ChatLine(i, model(),
+ width,
+ timestampWidth, senderWidth, contentsWidth,
+ senderPos, contentsPos);
+ if(atTop) {
+ h -= line->height();
+ line->setPos(0, y+h);
+ } else {
+ line->setPos(0, y+h);
+ h += line->height();
+ }
+ _lines.insert(start, line);
+ addItem(line);
+ }
+
+ // update existing items
+ for(int i = end+1; i < _lines.count(); i++) {
+ _lines[i]->setRow(i);
+ }
+
+ // update selection
+ if(_selectionStart >= 0) {
+ int offset = end - start + 1;
+ if(_selectionStart >= start) _selectionStart += offset;
+ if(_selectionEnd >= start) _selectionEnd += offset;
+ if(_firstSelectionRow >= start) _firstSelectionRow += offset;
+ if(_lastSelectionRow >= start) _lastSelectionRow += offset;
+ }
+
+ // neither pre- or append means we have to do dirty work: move items...
+ if(!(atTop || atBottom)) {
+ qreal offset = h;
+ int moveStart = 0;
+ int moveEnd = _lines.count() - 1;
+ ChatLine *line = 0;
+ if(end > _lines.count() - end) {
+ // move top part
+ moveTop = true;
+ offset = -offset;
+ moveEnd = end;
+ } else {
+ // move bottom part
+ moveStart = start;
+ }
+ for(int i = moveStart; i <= moveEnd; i++) {
+ line = _lines.at(i);
+ line->setPos(0, line->pos().y() + offset);
+ }
+ }
+
+ // update sceneRect
+ if(atTop || moveTop) {
+ updateSceneRect(_sceneRect.adjusted(0, h, 0, 0));
+ } else {
+ updateSceneRect(_sceneRect.adjusted(0, 0, 0, h));
+ emit lastLineChanged(_lines.last());
+ }
+
+}
+
+void ChatScene::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end) {
+ Q_UNUSED(parent);
+
+ qreal h = 0; // total height of removed items;
+
+ bool atTop = (start == 0);
+ bool atBottom = (end == _lines.count() - 1);
+ bool moveTop = false;
+
+ // remove items from scene
+ QList<ChatLine *>::iterator lineIter = _lines.begin() + start;
+ int lineCount = start;
+ while(lineIter != _lines.end() && lineCount <= end) {
+ h += (*lineIter)->height();
+ delete *lineIter;
+ lineIter = _lines.erase(lineIter);
+ lineCount++;
+ }
+
+ // update rows of remaining chatlines
+ for(int i = start; i < _lines.count(); i++) {
+ _lines.at(i)->setRow(i);
+ }
+
+ // update selection
+ if(_selectionStart >= 0) {
+ int offset = end - start + 1;
+ if(_selectionStart >= start)
+ _selectionStart -= offset;
+ if(_selectionEnd >= start)
+ _selectionEnd -= offset;
+ if(_firstSelectionRow >= start)
+ _firstSelectionRow -= offset;
+ if(_lastSelectionRow >= start)
+ _lastSelectionRow -= offset;
+ }
+
+ // neither removing at bottom or top means we have to move items...
+ if(!(atTop || atBottom)) {
+ qreal offset = h;
+ int moveStart = 0;
+ int moveEnd = _lines.count() - 1;
+ ChatLine *line = 0;
+ if(start > _lines.count() - end) {
+ // move top part
+ moveTop = true;
+ moveEnd = start - 1;
+ } else {
+ // move bottom part
+ moveStart = start;
+ offset = -offset;
+ }
+ for(int i = moveStart; i <= moveEnd; i++) {
+ line = _lines.at(i);
+ line->setPos(0, line->pos().y() + offset);
+ }
+ }
+
+ // update sceneRect
+ if(atTop || moveTop) {
+ updateSceneRect(_sceneRect.adjusted(0, h, 0, 0));
+ } else {
+ updateSceneRect(_sceneRect.adjusted(0, 0, 0, -h));
+ }
+}
+
+void ChatScene::updateForViewport(qreal width, qreal height) {
+ _viewportHeight = height;
+ setWidth(width);
+}
+
+// setWidth is used for 2 things:
+// a) updating the scene to fit the width of the corresponding view
+// b) to update the positions of the items if a columhandle has changed it's position
+// forceReposition is true in the second case
+// this method features some codeduplication for the sake of performance
+void ChatScene::setWidth(qreal width, bool forceReposition) {
+ if(width == _sceneRect.width() && !forceReposition)
+ return;
+
+// clock_t startT = clock();
+
+ qreal linePos = _sceneRect.y() + _sceneRect.height();
+ qreal yBottom = linePos;
+ QList<ChatLine *>::iterator lineIter = _lines.end();
+ QList<ChatLine *>::iterator lineIterBegin = _lines.begin();
+ ChatLine *line = 0;
+ qreal lineHeight = 0;
+ qreal contentsWidth = width - secondColumnHandle()->sceneRight();
+
+ if(forceReposition) {
+ qreal timestampWidth = firstColumnHandle()->sceneLeft();
+ qreal senderWidth = secondColumnHandle()->sceneLeft() - firstColumnHandle()->sceneRight();
+ QPointF senderPos(firstColumnHandle()->sceneRight(), 0);
+ QPointF contentsPos(secondColumnHandle()->sceneRight(), 0);
+ while(lineIter != lineIterBegin) {
+ lineIter--;
+ line = *lineIter;
+ lineHeight = line->setColumns(timestampWidth, senderWidth, contentsWidth, senderPos, contentsPos);
+ linePos -= lineHeight;
+ line->setPos(0, linePos);
+ }
+ } else {
+ while(lineIter != lineIterBegin) {
+ lineIter--;
+ line = *lineIter;
+ lineHeight = line->setGeometryByWidth(width, contentsWidth);
+ linePos -= lineHeight;
+ line->setPos(0, linePos);
+ }
+ }
+
+ updateSceneRect(QRectF(0, linePos, width, yBottom - linePos));
+ setHandleXLimits();
+
+// clock_t endT = clock();
+// qDebug() << "resized" << _lines.count() << "in" << (float)(endT - startT) / CLOCKS_PER_SEC << "sec";
+}
+
+void ChatScene::handlePositionChanged(qreal xpos) {
+ bool first = (sender() == firstColHandle);
+ qreal oldx;
+ if(first) {
+ oldx = firstColHandlePos;
+ firstColHandlePos = xpos;
+ } else {
+ oldx = secondColHandlePos;
+ secondColHandlePos = xpos;
+ }