return IStructuralChangeEvent.class;
}
@Override
public void handleLayerEvent(IStructuralChangeEvent event) {
IUniqueIndexLayer scrollableLayer = viewportLayer.getScrollableLayer();
if (event.isHorizontalStructureChanged()) {
viewportLayer.invalidateHorizontalStructure();
int columnOffset = 0;
int minimumOriginColumnPosition = viewportLayer
.getMinimumOriginColumnPosition();
Collection<StructuralDiff> columnDiffs = event.getColumnDiffs();
if (columnDiffs != null) {
if (minimumOriginColumnPosition < 0) {
// this is for handling of hide/show behaviour
// the value can only be -1 in case the column for which the
// minimum origin was set before
// was hidden, so we try to determine the correct value now
// if it is shown again
minimumOriginColumnPosition = scrollableLayer
.getColumnPositionByX(viewportLayer
.getMinimumOrigin().getX());
}
for (StructuralDiff columnDiff : columnDiffs) {
switch (columnDiff.getDiffType()) {
case ADD:
Range afterPositionRange = columnDiff
.getAfterPositionRange();
if (minimumOriginColumnPosition > 0) {
for (int i = afterPositionRange.start; i < afterPositionRange.end; i++) {
if (i < minimumOriginColumnPosition) {
minimumOriginColumnPosition++;
}
}
}
break;
case DELETE:
Range beforePositionRange = columnDiff
.getBeforePositionRange();
if (minimumOriginColumnPosition > 0) {
for (int i = beforePositionRange.start; i < beforePositionRange.end; i++) {
if (i < minimumOriginColumnPosition) {
columnOffset -= 1;
}
}
}
break;
}
}
}
int minimumOriginColumn = minimumOriginColumnPosition
+ columnOffset;
// in case of split viewports we use the min column position instead
// of the calculated value
if (viewportLayer.getMinColumnPosition() >= 0) {
minimumOriginColumn = viewportLayer.getMinColumnPosition();
}
// if the new origin is out of range (e.g. the last column in the
// viewport is moved
// to the frozen region, the minimum origin need to be updated in
// another way
int startX = scrollableLayer
.getStartXOfColumnPosition(minimumOriginColumn);
if (startX < 0 && minimumOriginColumnPosition > 0) {
int columnCount = scrollableLayer.getColumnCount();
if (columnCount == 0) {
// special case when all columns are hidden
startX = 0;
} else {
startX = scrollableLayer
.getStartXOfColumnPosition(columnCount - 1)
+ scrollableLayer
.getColumnWidthByPosition(columnCount - 1);
}
}
viewportLayer.setMinimumOriginX(startX);
}
if (event.isVerticalStructureChanged()) {
viewportLayer.invalidateVerticalStructure();
int rowOffset = 0;
int minimumOriginRowPosition = viewportLayer
.getMinimumOriginRowPosition();
Collection<StructuralDiff> rowDiffs = event.getRowDiffs();
if (rowDiffs != null) {
if (minimumOriginRowPosition < 0) {
// this is for handling of hide/show behaviour
// the value can only be -1 in case the row for which the
// minimum origin was set before
// was hidden, so we try to determine the correct value now
// if it is shown again
minimumOriginRowPosition = scrollableLayer
.getRowPositionByY(viewportLayer.getMinimumOrigin()
.getY());
}
for (StructuralDiff rowDiff : rowDiffs) {
switch (rowDiff.getDiffType()) {
case ADD:
Range afterPositionRange = rowDiff
.getAfterPositionRange();
if (minimumOriginRowPosition > 0) {
for (int i = afterPositionRange.start; i < afterPositionRange.end; i++) {
if (i < minimumOriginRowPosition) {
minimumOriginRowPosition++;
}
}
}
break;
case DELETE:
Range beforePositionRange = rowDiff
.getBeforePositionRange();
if (minimumOriginRowPosition > 0) {
for (int i = beforePositionRange.start; i < beforePositionRange.end; i++) {
if (i < minimumOriginRowPosition) {
rowOffset -= 1;
}
}
}
break;
}
}
}
int minimumOriginRow = minimumOriginRowPosition + rowOffset;
// in case of split viewports we use the min row position instead of
// the calculated value
if (viewportLayer.getMinRowPosition() >= 0) {
minimumOriginRow = viewportLayer.getMinRowPosition();
}
// if the new origin is out of range (e.g. the last row in the
// viewport is moved
// to the frozen region, the minimum origin need to be updated in
// another way
int startY = scrollableLayer
.getStartYOfRowPosition(minimumOriginRow);
if (startY < 0 && minimumOriginRowPosition > 0) {
int rowCount = scrollableLayer.getRowCount();
if (rowCount == 0) {
// special case when all rows are hidden
startY = 0;
} else {
startY = scrollableLayer
.getStartYOfRowPosition(rowCount - 1)
+ scrollableLayer
.getRowHeightByPosition(rowCount - 1);
}
}
viewportLayer.setMinimumOriginY(startY);
}