RefreshRange

[Administrator]

Hi

I do:
grid.Model[row, col].CellValue = c._value
grid.InvalidateRange(GridRangeInfo.Cell (row,col));

But it does not refresh graphically this single cell.
If i call grid.beginupdate /End update without parameter, no graphical update
if i use the Syncfusion.Windows.Forms.BeginUpdateOptions.Invalidate option it invalidates all the screen causing a huge CPU usage.
As my refresh occur often this is a problem
Any idea
thanks
B. Cliford

[Administrator]

Also what is the difference between
RefreshRange and InvalidateRange

[Administrator]

Hi,

I tried to reproduce the problem but it seems fine.

In GridPad, SampleGrid.cs add the following lines:

		protected override void OnCurrentCellControlDoubleClick(ControlEventArgs e)
		{
			trace = true;
			int o = 0;
				for (int n = 2; n < 10; n++)
				{
					for (int c = 4; c < 8; c++)
					{
						if (o % 2 == 0)
						{
							BeginUpdate(BeginUpdateOptions.InvalidateAndScroll);
							Model[n, c].CellValue = o;
							EndUpdate(true);
						}
						o++;
					}
			}
			trace = false;

			base.OnCurrentCellControlDoubleClick (e);
		}

		bool trace = false;

		protected override void OnCellDrawn(GridDrawCellEventArgs e)
		{
			if (trace)
				Console.WriteLine("OnCellDrawn: {0} / {1}", e.RowIndex, e.ColIndex);
			base.OnCellDrawn (e);
		}

You can kick off the test by double-clicking in a cell.

If you want to go the InvalidateRange route you could use the following code:

							GridStyleInfo style = new GridStyleInfo();
							style.CellValue = o;
							Model.SetCellInfo(n, c, style, StyleModifyType.Override, true, true);
							InvalidateRange(GridRangeInfo.Cell (n, c));
							Update();

If you keep having problems that might be specific to your app then. Best is then to upload a sample project that demonstrates the problem.

Stefan

>Hi
>
>I do:
>grid.Model[row, col].CellValue = c._value
>grid.InvalidateRange(GridRangeInfo.Cell (row,col));
>
>But it does not refresh graphically this single cell.
>If i call grid.beginupdate /End update without parameter, no graphical update
>if i use the Syncfusion.Windows.Forms.BeginUpdateOptions.Invalidate option it invalidates all the screen causing a huge CPU usage.
>As my refresh occur often this is a problem
>Any idea
>thanks
>B. Cliford

[Administrator]

I actually use the GrifPerf sample where i update frequently the cells.

is it of any importance ?

Thanks

[Administrator]

2 questions :
-on the code you gave me i don''t understand why do you have to go through:
Model.SetCellInfo(n, c, style, StyleModifyType.Override, true, true);
InvalidateRange(GridRangeInfo.Cell (n, c));
Update();

Using directly
grid.Model[row+1, col+1].CellValue is not good ?

What the update does ? CAn i call it for all my changes ?

Thanks

-why this method is never called on the gridperf sample :OnDrawCellDisplayText

[Administrator]

2 questions :
-on the code you gave me i don''t understand why do you have to go through:
Model.SetCellInfo(n, c, style, StyleModifyType.Override, true, true);
InvalidateRange(GridRangeInfo.Cell (n, c));
Update();

Using directly
grid.Model[row+1, col+1].CellValue is not good ?

What the update does ? CAn i call it for all my changes ?

Thanks

-why this method is never called on the gridperf sample :OnDrawCellDisplayText

[Administrator]

When you call

Model[row, col].CellValue = newValue

a lot is happening under the hood. Events are raised, possibly undo generation is created, notification is send out to all view to repaint.

SetCellInfo is a more advanced method. It allows suppressing events being sent out. It also gives a faster way for setting the style information directly into a cell.

See also the PopulateGrid sample for different method for filling the grid.

Stefan

>2 questions :
>-on the code you gave me i don''t understand why do you have to go through:
>Model.SetCellInfo(n, c, style, StyleModifyType.Override, true, true);
>InvalidateRange(GridRangeInfo.Cell (n, c));
>Update();
>
>Using directly
>grid.Model[row+1, col+1].CellValue is not good ?
>
>What the update does ? CAn i call it for all my changes ?
>
>Thanks
>
>-why this method is never called on the gridperf sample :OnDrawCellDisplayText

[Administrator]

Stefan

Excuse me to come back with the same question but it looks like all the grid if invalidated.

I actually use the GrifPerf sample where i update frequently the cells.

Is the Gridperf could affect the refresh method ?

Thanks again

[Administrator]

Which grid are you using? I made the changes below in the virtual grid code in that sample, and RefreshRange only seems to be triggering drawing the single cell being changed.

private void btnInitGrid_Click(object sender, System.EventArgs e)
{
	this.useDataTableList = this.checkBoxUseDataViewSort.Checked;
	this.calculateMaxColumnWidth = this.checkBoxCalculateMaximumWidth.Checked;
	this.recordCount = Convert.ToInt32(this.textBoxRecordCount.Text);
	this.zipCount = Convert.ToInt32(this.textBoxZipCount.Text);
	this.useOptimizedListChangedEvent = checkBoxUseOptimizedListChangedEvent.Checked;
	this.InitializeGrid();
	this.grid.DrawCell += new GridDrawCellEventHandler(grid_DrawCell);
	t = new Timer();
	t.Tick += new EventHandler(t_Tick);
	t.Interval = 500;
	t.Start();
}
Timer t;
Random r = new Random();
private void t_Tick(object sender, EventArgs e)
{
	this.grid[2,2].CellValue = r.Next(100);
	this.grid.RefreshRange(GridRangeInfo.Cell(2,2));
}
int a = 0;
private void grid_DrawCell(object sender, GridDrawCellEventArgs e)
{
	Console.WriteLine(string.Format("{0}-({1},{2}", a++, e.RowIndex, e.ColIndex));
}