VB Graph UAE/"Error Creating Graph Image" for 256 Color Driver

ID Number: Q80778

1.00

WINDOWS

buglist1.00

Summary:

When Windows 3.0 is configured to use a VGA 256 color video driver,

attempting to save a graph file to disk when using the Visual Basic

Graph custom control will generate one of the following messages:

Unrecoverable Application Error

-or-

Error Creating Graph Image

Microsoft has confirmed this to be a problem in the Graph control in

Microsoft Professional Toolkit for Microsoft Visual Basic programming

system version 1.0 for Windows. We are researching this problem and

will post new information here as it becomes available.

More Information:

The following is a pseudocode example that will generate an "Error

Creating Graph Image" message.

Steps to Reproduce Problem

--------------------------

1. From the File menu in VB.EXE, choose Add File, and select the custom

control called GRAPH.VBX (this is the custom control that is shipped

with the Professional Toolkit for Visual Basic).

2. Add a graph to the form by selecting the Graph control from the

Toolbox, and either double-click the item or click the Graph

control once and draw it on the form.

3. Double-click on the form to bring up the Code window, and add the

following code:

Sub Form_Click()

Graph1.ImageFile = "testfile" 'sets the name of the file to be

'saved to disk

Graph1.DrawMode = 3 'set the DrawMode to Blit to make the graph

'file a bitmap

Graph1.DrawMode = 6 'set the DrawMode to Write

'This is a transient property value for the DrawMode property of

'the graph control. The file is written to disk.

End Sub

4. From the Run menu, choose Start to start the newly created

application.

5. Click anywhere on the form outside the graph.

An "Error Creating Graph Image" message will be displayed.

Note: When Windows 3.0 is configured to use a 16 color VGA video

driver, no error message is generated and the file will be saved to

disk with the arbitrary name TESTFILE.BMP.

Also note that setting the DrawMode property of the graph to 2 instead

of 3 will make the graph a Windows metafile. If, in the example above,

you save the graph as a metafile, it will result in an "Unrecoverable

Application Error" message.

The DrawMode properties 2 and 3 can be set either at design time or at

run time, but this has no effect on the problem. Setting the DrawMode

property to 6 will fire the event to save the image file to disk. This

image is saved either as a Windows metafile (DrawMode = 2) or as a

bitmap file (DrawMode = 3).

Additional reference words: 1.00