Enhance VFP9 Report using GDI+

During this weekend, I have came up a simple sample that enhance VFP9 report using GDI+, by refering couple of resources, such as GDI+ on MSDN library, www.News2News.com, FoxProAdvisor and helps from UT members especially Lisa Nicholls and Anatoliy Mogylevets.
Some wrapper classes and methods are implemented. It does not cover all of GDI+ functions, only those used in this project. It would take quite long time to implement all of them. Therefore, it would be good if FoxTeam could provide GDI+ wrapper classes, since they should be more familiar with GDI+ functions.

During this VFP9 Report project, I was stuck on couple of places which I think should be pay attention on:

1. Don't call GDI+ cleanup code while graphics object killed (GdiplusShutdown & GdipDeleteGraphics) if you are using GDI+ graphic handle from VFP report for drawing. Otherwise, your report will hang.

2. GDI+ use ARGB (Alpha, Red, Green, Blue) color value instead of RGB. I have wrriten color class to handle the conversion.

3. Some GDI+ API GdipFillRectangle doesn't work for me. I got to use GdipFillRectangleI instead. The difference between both functions is GdipFillRectangleI receive coordinate parameter as INTEGER, but GdipFillRectangle receive REAL. I used to change my data type to LONG in API declaration, but doesn't help.

4. Function GdipDrawLineI works fine in drawing non-straigt line.

x1 = 100

y1 = 175

x2 = 500

y2 = 176

But not horizontal or vertical line.

x1 = 100

y1 = 175

x2 = 500

y2 = 175



= GdipDrawLineI(x1, y1, x2, y2)

if anyone has any ideas, pls comment.

Back to the sample. This sample generate student exam score report, displaying student score field by text and graphically (thermometer). [Screenshot]

Here is the code in ReportListener.Render()

LPARAMETERS nFRXRecno, nLeft, nTop, nWidth, nHeight, ;

            nObjectContinuationType, cContentsToBeRendered, ;

            GDIPlusImage



LOCAL loGraphics, loColor, loSolidBrush, loPen, lnScoreWidth



THIS.setFRXDataSession()



SELECT frx

GO (nFRXRecno)



*-- I have keyed in "CHART" in Rectangle control's user column

*-- to indicate that is the control used for drawing purposes.

*-- Check if it is the border we want

llChart = frx.User = "CHART"



this.setCurrentDataSession()



IF llChart

	loGraphics = CREATEOBJECT("Graphics")



	*-- Set report GDI+ handler to custom graphics class

	loGraphics.GetFromExternal(THIS.GDIPlusGraphics)



	*-- Get color ARGB value from color class

	*-- Red color is used in this sample.

	loColor = CREATEOBJECT("Color", 255,255,0,0)

	loPen = CREATEOBJECT("Pen", loColor.Color, 4)



	loSolidBrush = CREATEOBJECT("SolidBrush", loColor.Color)



	*-- Draw thermometer rectangle border

	loGraphics.DrawRectangle(loPen.Pen, nLeft  , nTop , ;

				nWidth , nHeight )



	*-- Calculate the width thermometer value bar width

	lnScoreWidth = (Exam.Score / 100 * nWidth)



	*-- Fill color into rectangle but adjust the position and ;

	*-- reduce size from original one to have special effect. 

	loGraphics.FillRectangle(loSolidBrush.SolidBrush, ;

                                nLeft + 20 , ;

                                nTop + 20 , ;

                                lnScoreWidth - 40, ;

                                nHeight - 40)



	STORE .NULL. TO loSolidBrush, loColor, loGraphics

	NODEFAULT

ELSE

	DODEFAULT(nFRXRecno, nLeft, nTop, nWidth, nHeight, ;

                 nObjectContinuationType, cContentsToBeRendered, ;

                 GDIPlusImage)

ENDIF

Click here to download the full sample, for those whose interested.

[NOTE: It is a test program. Run / use this program at your own risk.]