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Chapter 8: Using Image Resources
Rapid-Q Documentation by William Yu (c)1999 Chapter 8

8. Using Image Resources

Most Windows programming languages offer support for .RES (Resource) files. A Resource file is nothing more than a collection of images (plus resource strings and data). In this chapter, you'll learn about Image lists, how to embed resources in your executable, and how to properly use them in your applications.

8.1 Supported RESOURCES
Rapid-Q only "directly" supports image resources, ie. just Icons and Bitmaps. So what exactly is the difference between loading a picture at run-time, or loading resource handles? For one thing, whenever you declare a resource handle, that picture file is automatically embedded within your executable. Here's an example:

     DIM Form AS QForm

     Form.ICOHandle = ICO_TEST
     'Form.Icon = "C:\ICONS\TEST.ICO"
The file C:\ICONS\TEST.ICO is embedded within your executable, which means you don't need to include TEST.ICO if you plan on distributing your .EXE program. Rapid-Q doesn't generate .RES files for you, and it can't handle other people's .RES files either. Most languages you'll see have a .RES file, but you can't use them in Rapid-Q, you'll have to extract the pictures within it, and use the $RESOURCE handle directive to include them in your application. It is also possible to do this:
     Form.ICOHandle = ICO_TEST

     DIM Image AS QImage

     Image.Icon = Form.Icon
Image.Icon normally accepts a string value, but if no string is specified, it'll read the previously cached icon. In this case, we're loading Form.Icon to our "cache" and Image.Icon will read from it. So what does this do?
     Image.Icon = Form.Icon + Form2.Icon
This will load Form2.Icon into the cache, so Image.Icon will copy Form2.Icon. However, please note that you can't assign Icon Handles, for example:
     Image.IcoHandle = Form.IcoHandle
The parser will try to look for a resource handle, but won't find one.

8.2 Introduction to Image lists
You may want to refer to the Appendix on the properties, and methods of QImageList. An Image list is an array of icons and/or bitmaps. They are ordered from 0 to N. The first image you add will be index 0, the next index 1, etc... an image list store images of FIXED width and height. Anytime you change the Width or Height property, you're ultimately clearing the entire array. Note, this does not mean you can't add a 100x100 BMP file when your image list width is 32. It just means your BMP will be resized, whether you wanted that or not.
    DIM ImageList AS QImageList
        ImageList.Width = 32
        ImageList.Height = 32
        ImageList.AddBMPFile("app.bmp", 0)
You can add icons or bitmaps in any order. As before, you can also add images from the "cache" if no filename was specified. As before:

8.3 Other kinds of Resources
You can include any kind of resource to your Rapid-Q program, but how can you use these other kinds? For example, if I include a .WAV file as a resource, how can I use it in my PLAYWAV routine? Well, since PLAYWAV can take resource handles, you can just pass it as a parameter:
    PlayWav(Bomb_WAV, 1)      '-- 1 = background play

    SLEEP 5                   '-- Wait until wav is finished
As for other types, you can extract the resource to be manipulated.
    $RESOURCE Whatever_TYPE AS "text.txt"
    ExtractResource(Resource(0), "text.txt")
After you're done using it, you can simply delete the file. There are a wide range of uses for extracting resources, you can even use this technique in an installation program. For more information on EXTRACTRESOURCE, RESOURCE, and RESOURCECOUNT, please see Appendix C: Other reserved keywords

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