Hi,
I would like to add a behaviour to my grid, so that all child rows are fully visible when the user expands a row.
So when expanding a row, and the child rows exceed the available space below the root row, it should scroll down far enough for all (or at least as many as possible) child rows to be visible.
Also, I would prefer a solution without DataPresenterCommands.RecordBelow etc. because selection changes are expensive (each selection change loads certain data in my grid) and selection changes may not be possible at all if the user is currently editing a row.
Can you provide me with any hints on such an implementation?
Hello,
Thank you for your post. I have been looking intot he functionality that you are trying to achieve and I can suggest using the BringRecordIntoView method of the XamDataGrid and its RecordExopaned event. In the event handler for the event you can call the BringRecordIntoView method and pass the first child record of the record that is expanded as parameter for the method. This way the XamDataGrid will scroll the first child record of the currently expanded record at top and this will result in showing as much child records as possible. I have created a sample application for you, that demonstrates how you can implement this approach.
If you need any further assistance please do not hesitate to ask.
Sincerely,
Krasimir
Developer Support Engineer
Infragistics
www.infragistics.com/support
Thanks, but not quite yet what I need.
1. The parent row still needs to be visible. I achieved that by adding another line of code below yours:
xamdataGrid1.BringRecordIntoView((e.Record as DataRecord).ChildRecords[0]);xamdataGrid1.BringRecordIntoView((e.Record as DataRecord));
2. Scrolling must not be done if all child records are actually visible. I tried comparing to GetRecordsInView(true), but this method does not seem to list child records, so I cannot check if all child rows are in the list of visible rows.
3. It should not scroll to the top, but only as far as necessary to avoid confusion.
Can you help me with these issues?
Thank you for your reply. I have been looking into your question and I have modified the sample application in order to implement you requirements. I have used the GetRecordsInView method of the XamDataGrid, in order to get the child records that are visible after a record is expanded. Since in the RecordExpaned event the Records in view are not already changed I have used a Dispatcher in order to determine the exact count of the visible child records. If all the child records of the expanded record have height bigger than the ActualHeight of the XamDataGrid, I am calling the BringRecordIntoView as in the previous example. If the all the child records have height smaller the XamDataGrid, I am calculating the child rows that are out of view and add this count to the VerticalOffest property of the ScrollInfo of the XamDataGrid. By doing so I am scrolling the control vertically, so the last child record is visible. This approach will work only when the records of the XamDataGrid has fixed height and this number is known, we are not able to get the actual height of all child records, in order to calculate whether the space in the XamDataGrid is enough to show them due to the virtualization of the control, which causes the visual elements of the records to not get loaded until the records should go into view.
If you need any further assistance on the matter please do not hesitate to ask.
Thanks, that is much closer. I'm using a more dynamic "default height" approach though:
double defaultHeight = DataRecordPresenter.FromRecord(recordsInView.FirstOrDefault(x => x.RecordType == RecordType.DataRecord)).ActualHeight;
I am very glad that the approach I have suggested helped implementing the functionality that you are looking for. If you need any further assistance on the matter please do not hesitate to ask.