Birt table dynamically format cells

Question

Is it possible to dynamically format my report at run-time? I need to be able to set a style of a cell based upon what column and the value of the cell. So if column3 has a cell with a value of 23 .setStyleName("customStyle");. I am using BIRT 4.2.2.

currently I have something like this:

// table detail
RowHandle tabledetail = (RowHandle) table.getDetail().get(0);
for (int i = 0; i < cols.size(); i++) {
    CellHandle cell = (CellHandle) tabledetail.getCells().get(i);
    DataItemHandle data = designFactory.newDataItem("data_" + cols.get(i));

    data.setResultSetColumn(cols.get(i));

    // data.getContent(from, cols.get(i)).getcontents();

    cell.getContent().add(data);

    // format every other columns
    if (i == 3) {
        cell.setStyleName("LabelHeader");
    }
}

But for some reason this changes the background color of every cell in the fourth column not a cell with 3 in it.

I read this Eclipse Birt - Set style cell table dynamically with Event Handler and the only answer was to use a script. I don't want to use a script I would like to change the style in java.

I need to be able to evaluate a cells contents and set a style based upon that.

Answer 1

You need to understand how BIRT works to understand why your code can't work. BIRT has a design phase (where you don't have any values). When the report is rendered, BIRT will parse the design and expand it following certain rules (for example, it will copy template rows of data tables so you get one row of output for each row of data that your database returns even though your design has only one row).

That means you can't achieve what you want at the design phase - there is no way to get at the values at that time.

What you need is either an event handler or dynamic formatting. The latter is more simple.

If you want to use the event handler, then hook into the onFetch event of the data source. It will fire after every row that was fetched from the database. At this time, you can examine the data and change the template. Note: You must set a useful value via setStyleName() for every row. So you must have two styles ("is not 3" and "is 3") and apply the one which fits.

It's possible to do that from Java but the most simple solution is really to write a small piece of JavaScript. You can then use Java code to install this piece of JavaScript in the design.

You could in theory call Java directly from event handlers but I never saw any useful documentation for this.