Tooltip and AutoEllipsis

[Jeroen Eikmans]

Hi,

Ik would like to display a tooltip on a cell when the text in the cell has an ellipsis.
The AutoEllipsis nicely adds the Ellipsis when the text is to big for the cell, but instead of having the users change the width of the column i would like a tooltip which shows the entire text.

I couldn't find documentation on how to do this so if someone can point me in the right direction...

Kind regards

[Svett]

Hi Roel Martens,

You can measure the height and width of the text and then depending on that to compare it with the cell dimensions. If the text exceeds the size of the cell, then you can show your tool tip text for the specified cell. You can easily achieve that behavior on the ToolTipTextNeeded event. You should use TextPart object to measure text height and width.

private void radGridView_ToolTipTextNeeded(object sender, Telerik.WinControls.ToolTipTextNeededEventArgs e)
{
    GridDataCellElement dataCell = sender as GridDataCellElement;

    if (dataCell != null)
    {
        TextPart textPart = new TextPart(dataCell);
        SizeF size = textPart.Measure(new SizeF(float.PositiveInfinity, float.PositiveInfinity));
        SizeF sizeInCell = textPart.Measure(new SizeF(dataCell.ColumnInfo.Width, float.PositiveInfinity));

        string toolTipText = null;

        float cellWidth = dataCell.ColumnInfo.Width - dataCell.BorderWidth * 2;
        float cellHeight = dataCell.Size.Height - dataCell.BorderWidth * 2;

        if (size.Width > cellWidth || cellHeight < sizeInCell.Height)
        {
            toolTipText = dataCell.Text;
        }

        dataCell.ToolTipText = toolTipText;
    }
}

I hope this helps.

Kind regards,
Svett
the Telerik team

[Jeroen Eikmans]

Hi Svett,

This works perfectly! Thanks very much.

Kind regards

[Grant]

Hi Svett, I'm using a recent build of the Telerik WinControls (2011.1.11.419) and would like to use this functionality. The ellipses work great; they make the grid look more polished. The tooltip feature sounds very useful, but I'm having trouble implementing it. I pasted your code below exactly as-is (other than adding a single line to enable the tooltip if tooltiptext has a value) and registered the event with my grid. Sometimes when I hover the mouse over a cell in which the text is cut off, I get the correct cell content in the tooltip. I'll hover over a few others and they all work fine. But then suddenly I'll hover over another cell and the tooltip that pops up will contain content from one of the previous cells. I stepped through the code line by line... dataCell is pointing to the correct cell, it's "value" property contains the cell's correct text, and the correct text is assigned to tooltiptext. But then I hit F5 to continue running the app and the tooltip that pops up is the text from another cell completely. Any ideas? Thanks!

[Svett]

Hi Grant Winney,

There is a know issue regarding tool tips in Q1 2011 SP1 (2011.1 11.419). We addressed the issue in our latest internal build (2011.1 11.510) which you can download from your account. I recommend that you try it. Also you should use a modified version of my previous code snippet:

private void radGridView1_ToolTipTextNeeded(object sender, Telerik.WinControls.ToolTipTextNeededEventArgs e)
{
    GridDataCellElement dataCell = sender as GridDataCellElement;

    if (dataCell != null)
    {
        TextPart textPart = new TextPart(dataCell);
        SizeF size = textPart.Measure(new SizeF(float.PositiveInfinity, float.PositiveInfinity));
        SizeF sizeInCell = textPart.Measure(new SizeF(dataCell.ColumnInfo.Width, float.PositiveInfinity));

        string toolTipText = null;

        float cellWidth = dataCell.ColumnInfo.Width - dataCell.BorderWidth * 2;
        float cellHeight = dataCell.Size.Height - dataCell.BorderWidth * 2;

        if (size.Width > cellWidth || cellHeight < sizeInCell.Height)
        {
            toolTipText = dataCell.Text;
        }

        e.ToolTipText = toolTipText;
    }
}

If the issue still occurs, I would kindly ask you to open support ticket. There you can enclose a sample project where the issue is presented.

Best wishes,
Svett
the Telerik team

[Lily]

With this way, can you change the size of the font?

[Dess | Tech Support Engineer, Principal]

Hello, Lily,

According to the provided information, I am not sure whether you are asking about the font of the cell itself or the tool tip. 

You can change the cells' font by handling the CellFormatting event. 

Thus, the TextPart will measure the desired value of the cell considering the font as well.

However, if you want to change the font of the tool tip, you can enable the ToolTip.OwnerDraw property and handle the Draw event of the tool tip where you can draw desired text with the desired font and fill color. Note that the ToolTip is the standard ToolTip and you can customize it as it demonstrated in the following MSDN articles: 
https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.tooltip.ownerdraw?redirectedfrom=MSDN&view=netframework-4.8#System_Windows_Forms_ToolTip_OwnerDraw 
https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.tooltip.draw?view=netframework-4.8 

I hope this information helps.

Regards,
Dess | Tech Support Engineer, Sr.
Progress Telerik