Have been up all night trying to figure this one out. I am using an Infragistics.Win.UltraWinGrid.UltraGrid. The DataSource for the grid is a BindingSource that uses a custom data structure. Binding and property updates are working fine. Grid is readonly.I want to change the color (toggle) of a row if the underlying value changes. Here is a very simplified snippet of my original code using the recommended InitializeRow event (note, for simplification I am just coloring the whole row for the example, whereas actually I am coloring a cell in my application):private void ugWatchlist_InitializeRow(object sender, Infragistics.Win.UltraWinGrid.InitializeRowEventArgs e){ if (!e.ReInitialize) return; Infragistics.Win.Appearance app1 = new Infragistics.Win.Appearance(); app1.BackColor = Color.Green; Infragistics.Win.Appearance app2 = new Infragistics.Win.Appearance(); app2.BackColor = Color.Red; if (e.Row.Appearance.BackColor.Name != Color.Green.Name) e.Row.Appearance = app1; else e.Row.Appearance = app2;}However, the color change works only once (and rows turn red on the firs t update and stay that way). According to the code, the color should toggle on each update. I can confirm in the debugger that the BackColor property is indeed changed but not reflected by the UltraGrid.Am I missing something here? I have gone through all the samples and examples and couldn't find a solution to this problem. Please help.
Hi,
I suggest you try with a different version of NetAdvantage and see if the error is still happening. If the issue is not resolved then submit a case to developer support.
Magued
Thanks for all the suggestions. I figured out the problem some days back and just posting the update here. I fixed the issue by firing a timer on each update and resetting the value when the timer gets triggered.
However, now I have to "flash" the cell based on "how" the value changed, i.e. if the value is numeric and it decreased I have to flash it with red, otherwise green. Any suggestions how to get the "previous" value in a cell just before initializeRow is fired?
So how's the performance?
I don't think the speed of adding items to the colorizer will be an issue in itself. The only time you might run into a performance issue with this code is if you end up building up a huge amount of cells in the colorizer at once.
Looping through the Cells every time the timer ticks could become an issue if you have thousands of cells in the list at once. If that's the case, I guess it might be possible to take an alternative approach where you don't process all of the cells all the time, but instead move the processing into the DrawFilter so that the cell is only processed when it has a UIElement on the screen. The problem with that approach is that the list could grow and grow and the cells that are out of view might never get cleared out, so it would end up eating memory. So there would have to be some other cleanup mechanism or a limit on the size of the list.
Hi Mike, i'm back and working on implementing this. i still have the code you sent and it does make sense. However my challenge is getting the colorizer to fire from the underlying datasource changing, as opposed to the click of a button like your example.
i cannot get the grid to pick up underlying datasource updates. i'm using a single typed BindingList with two bindingviews. and while the grid is definitely updating in realtime i'm not able to capture its events.
the only thing that i have working is hooking into the listchanged event of the underlying list and capture "ItemChanged", "ItemAdded" events. But i cannot figure out how to find those updated items in the grid.
what am i doing wrong?
Hi Al,
Well, you are going to be limited by what your data source exposes. I think using the ListChanged interface is probably a good idea. The ListChanged notifications pass you an index, which is an index of the row that was changed in the data source. If your grid is filtered or sorted, finding the matching row in the grid might not be simple, though, especially if you are dealing with child rows
The grid's Rows collection has method called GetRowWithListIndex that will help. On the root band, this is straightforward. You can use the index you get from ListChanged to find the correct row. For a child row, you will have to find the parent row by it's ListIndex first, and then find the child row in the child rows collection.
I don't think ListChanged gives you which field was changed, though. So the only way to determine that would be to update whatever is changing the data so that it also sends you some kind of notification with more detailed info.
ok. yes i have just the root band. well i'm using notifypropertychanged for all the properties in my class and hoped to listen to those. but doesn't appear to be happening when bound to data source. i tried to capture the gridAftercELL_update event but that wasn't firing for me when the cell was updated from the underlying data source. i guess it only works from modifiing the data directly (by hand/code)
i've turned your gridcellcolorizer into a gridrowcolorizer which appears to work though i'm still testing. It does use the listchanged event which is a bit silly, i need to determine update vs initial load time, etc. if coloring at a cellular level is to involved then i will pass. it's not worth the effort/risk i guess.
thanks
Al Maiz said:well i'm using notifypropertychanged for all the properties in my class and hoped to listen to those. but doesn't appear to be happening when bound to data source.
I'm not sure I follow you there. If you have your own custom class and implement this interface and you are setting properties and the interface notification is not firing, then something is wrong with your interface implementation. No? Unless something in your class is bypassing the property setter or changing the property values without firing the notification. This has nothing to do with the grid or data binding.
Al Maiz said: i tried to capture the gridAftercELL_update event but that wasn't firing for me when the cell was updated from the underlying data source.
Yes, that's correct.
OK. i thought i was. i'm able to get the notifyprop changed event to fire when i directly set a value for one of the properties . i have to wire up to each property with a shared handler.
thanks for the help