How to specify a row background in table with iText5 - itext

Question

When creating a PDF table with iText5, it is possible to create a table background by implementing a PdfPTableEvent and a cell background by implementing a PdfPCellEvent.
But what about a row background? How can I create that?
The reason is because I want to create a calendar table like in the image below:

Answer 1

Actually, you have included the answer in your question: you have to use a table event. Take a look at the RowBackground example. It contains a table event RowBackgroundEvent that allows you to create a table event to draw the background of a single row.
public class RowBackgroundEvent implements PdfPTableEvent {
// the row number of the row that needs a background
protected int row;
// creates a background event for a specific row
public RowBackgroundEvent(int row) {
this.row = row;
}
/**
* Draws the background of a row.
*/
#Override
public void tableLayout(PdfPTable table, float[][] widths, float[] heights,
int headerRows, int rowStart, PdfContentByte[] canvases) {
float llx = widths[row][0];
float lly = heights[row];
float urx = widths[row][widths[row].length - 1];
float ury = heights[row - 1];
float h = ury - lly;
PdfContentByte canvas = canvases[PdfPTable.BASECANVAS];
canvas.saveState();
canvas.arc(llx - h / 2, lly, llx + h / 2, ury, 90, 180);
canvas.lineTo(urx, lly);
canvas.arc(urx - h / 2, lly, urx + h / 2, ury, 270, 180);
canvas.lineTo(llx, ury);
canvas.setColorFill(BaseColor.LIGHT_GRAY);
canvas.fill();
canvas.restoreState();
}
}
This is how this event is used:
public void createPdf(String filename) throws SQLException, DocumentException, IOException {
// step 1
Document document = new Document(PageSize.A4.rotate());
// step 2
PdfWriter.getInstance(document, new FileOutputStream(filename));
// step 3
document.open();
// step 4
PdfPTableEvent event = new RowBackgroundEvent(3);
PdfPTable table = new PdfPTable(7);
table.setTableEvent(event);
table.getDefaultCell().setBorder(Rectangle.NO_BORDER);
for (int i = 0; i < 10; i++) {
for (int j = 1; j < 8; j++) {
table.addCell(String.valueOf(j));
}
}
document.add(table);
// step 5
document.close();
}
As you can see, we want a background for the third row. The result looks like this:
You can tweak the llx, lly, urx, and ury value if you want to adapt the size of the background bar.
If you can draw the background of a single row, you can extend the code to draw the background of more than one row.