05-30-02

Version Tracking by Erick Tejkowski

Ever wonder how REALbasic programmers implement the "Check for Updates" feature found in so many apps today? This week we'll look at a simple example of how to do this.

Build the Interface

Launch REALbasic and open Window1. To this window, add a PushButton, an EditField, a StaticText control, a ChasingArrows control, and a Socket. Change the properties of each to match the following table:

Control Type	Name	Other Info
EditField	EditField1
PushButton	PushButton1	Caption = "Check Version"
Socket	httpSocket1	super = "httpSocket"

Notice that you don't have an httpSocket in your project yet. If you want to follow along, download the httpSocket from Dan Vanderkam and drag the httpSocket class into your project. Then go back and change the Super property of the httpSocket1 to httpSocket. If you don't feel like finding the parts, you can download the completed project at the end of this tutorial.

Arrange the interface to your liking. For example, it might look like this:

Source Code

Double click PushButton1 to open the Code Editor and add the following code to its Action event:

  
  dim theURL as string
  
  // a sample version-number-file on the resex server
  theURL = "http://www.resexcellence.com/realbasic/downloads_02/05-30-02_version.txt"
  
  // Display the ChasingArrows
  // to show we are at work
  ChasingArrows1.visible = TRUE
  
  // Prep the Socket and get the file (as a variable)
  // The resulting variable will be available in the
  // DLFinished event of httpSocket1
  httpSocket1.httpSocket
  httpSocket1.storeInFile=true
  
  httpSocket1.Method = 1
  theURL = httpSocket1.FormatURL(theURL)
  httpSocket1.GetFile(theURL)
  
  

Finally, navigate to the DLFinished event of httpSocket1 and add this code:

  dim myversion as integer
  
  statictext1.text=txt 
  myversion=val(editfield1.text)
  
  // Hide the ChasingArrows
  // to show we are at finished
  ChasingArrows1.visible = FALSE
  
  if val(txt)>myversion then
    MsgBox "You need to update!"
  elseif val(txt)<myversion then
    MsgBox "Your version is newer than the currently available version!"
  else
    MsgBox "Your software is current."
  end if
  

Conclusion

That's it...short and sweet. The code downloads a file I've placed on the Resex server which holds a version number. Once downloaded, we simply compare the version number that is in that text file with the version number we've designated for this application. Then, we display an appropriate message. You can download the finished project here. See you next week!

5-28-02

REALbasic News by Erick Tejkowski

DrawControl and Custom Icon Francis Lessard has posted two new REALbasic plugins: DrawControl 1.0 and Custom Icon 1.0. Find more information here.

LetsSee for OS X Irony software announced that its popular graphics browser LetsSee is now available for OS X. The most recent version; 1.8.2 has been ported to Apple¹s super-modern operating system: Mac OS X. LetsSee is a graphics browser that gives you fast and easy access to your favorite pictures and movies, flash and mp3 files. You can edit and save your images. You can modify and batch change file properties like name, file-comment and creator. Present your media files as a continuous slideshow and create a html photo gallery and a lot more. Made with REALbasic!

Office Constants Check out these new modules for encapsulating all of the constants that can be used in VBA in conjunction with the REALbasic Office Automation plugins.

• Excel Constants
• MSOLib Constants
• Powerpoint Constants
• VBA Constants
• Word Constants

Pigmy Are you a Pixie user? If so, check out Pigmy from Seth Willits.

PodUtil 1.0b3 KennettNet are pleased to announce the release of PodUtil 1.0b3 for Mac OS 8.5 - 9.x.x and for Mac OS X. This is an update to the already popular program and is still in beta, made with REALbasic. The 1.0 beta 3 update sports a redesigned interface, a better, hierarchical music list, and a massive improvement to vCard support. There many more improvements and enhancements, see the PodUtil web page for more info.

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