Multipage TeeChart Gantt: how to stop first page displaying after deselecting a series in legend on last page

Question

I have an application that uses a TeeChart Gantt chart (v2.0.2670.2652).

I am developing in .NET 2.0 using VS2010 SP1 on 32-bit Windows 7.

This chart displays forest harvesting crews schedules over time. It has forest harvest unit on the y-axis and date on the x-axis. Each harvesting crew is a series. Initially the chart shows a 14-day time frame. The date range can be altered by selecting new start and finish dates. If the user selects a date range more than can be displayed on one page (e.g. 6 months or 24 weeks), the chart displays a scroll bar below the x-axis and this allows the user to scroll to the right to see all the schedules. The legend is displayed to the right on the scrolling pane.

The legend has checkboxes enabled so that the user can select or deselect the crews to be displayed. Here's the usability problem .... I have noticed that when the first crew is deselected the chart flicks back to the left-most position. If the user wants to deselect any additional crews they have to scroll back all the way to the right to display the legend again. However when subsequent crews are deselected the chart does not flick to the left-most position. This behaviour is not very user friendly. I would prefer that the chart stayed displaying the chart legend.

I have not been able to trace the cause of the first flick back to the left-most position. Even after removing my click legend event handler the chart did the same thing. I did notice that if you click the panel the chart is on it will also display the first page.

Naturally the chart is embedded in some quite complicated logic and would take me a little while to extract it so I can display this behaviour in a simple example. Wondering if anyone else has experienced similiar behaviour and if there is a workaround?

Thanks for any answers, suggestions and/or comments anyone has.

Yeray Yeray · Accepted Answer · 2012-02-02T12:20:05

I've looked in the Steema Support Forums but I don't find anything similar reported. You could give it a try: http://www.teechart.net/support/search.php

I've also tried to reproduce it with the following example but apparently the second page is still displayed when the first series is unselected in the legend.

        tChart1.Legend.CheckBoxes = true;

        for (int i = 0; i < 5; i++)
        {
            new Steema.TeeChart.Styles.Gantt(tChart1.Chart);
            tChart1[i].FillSampleValues();    
        }

        tChart1.Page.MaxPointsPerPage = 2;
        tChart1.Page.Next();

You could also give a try to the actual evaluation version (v4.1.2012.01030) to see if the behaviour has changed over the years.

Multipage TeeChart Gantt: how to stop first page displaying after deselecting a series in legend on last page

1 Answers