(Tool)Band Aid

So, I recently completed writing a Desk band for windows. What is a desk band, you ask? Well, your windows start bar is the home for several desk band objects. These are basically COM objects that support a bunch of interfaces and register themselves in appropriate places so that windows knows to load them.

In short, you register your windows class and it gets put in the toolbar. Nearly the same code can work in multiple places in IE, Explorer, and in the Start Bar. So, I learned a few lessons:
  • It is far easier to do your initial development so the band will work in the IE toolbar than in the start bar. This lets just run the COM object (and automatically start IE) rather than manually starting up the desk band, and attaching to the Explorer process. When you get most of what you need done, you can test it in the Start bar.
  • A conditional compilation switch in your code will make sure that you don't accidentally register the release version of your desk band object to run in IE (if you don't intend it to).

So, I based my deskband on the sample SDK code from Microsoft. But it has a few problems.

  • It registers fine. The normal "regsvr32 myobj.dll" works great, but it doesn't implement any unregister functions. You have to write those yourself. Now, I know that if you use ATL or MFC that you can get that for basically free, but it seems a bit of an overkill if you are doing just a small simple COM object. And besides, you have to do custom registration for it to get loaded automatically anyway.
  • The window with the text is kind of ugly. I really wanted a desk band that didn't have a big square box.

So, here's what I did to get rid of the box...

First of all, I registered the window class with a background color of NULL. That way, it won't automatically erase the background with blue. I also changed the flags so that there isn't a black border around the window contents.

The next thing I did was implement a handler for the Erase method that windows will call whenever the window needs to be erased. MSDN says that you should do this. If you don't do this, you'll get text that writes on top of itself over and over, works fine until your text changes. Then it looks like some kid scribbled on the screen. But at least you have the same background that the toolbar has. (there are some people that don't use the blue jelly toolbar, they must like grey).

So, how do we keep the nice gradient, or the grey background, or whatever they have as a background while we're drawing on it all the time? StretchBitBlt. Enough said.

... What? That wasn't enough said?

Ok, so here's what I did. realizing that the gradient is vertical, when my erase event gets invoked, I just stretch bit blit whatever is on the left hand side of the draw window all the way across my drawing rect. Then, I text out on top of that. It's easy once you figure it out.

Comments

Post a Comment

Popular posts from this blog

Database Projects, SQL Unit Tests, and TeamCity

Image
Continuous Integration  is a really good idea, especially when you are working with a team of developers. There are lots of tools out there that can help your team build better quality into your application. TeamCity by JetBrains is one such tool that has been around for awhile; specifically, it is the one that my company uses. Visual Studio has Database Projects   SQL Server Data Tools  to address some of the inconsistencies that developers face when using a database as a storage layer; Things like version control and consistent deployment. It also includes SQL unit tests , which fills a huge gap if any  of your logic is in the database. Many organizations moved away from logic in the database years ago because it was tricky (at best) to verify logic on the data tier, of course, they were also making changes directly to the database itself... but I digress. If you are using SQL Server Data Tools, and run your unit tests locally, it is a joy to behold. Your data...
Read more

Building nice XML from SQL Server Tables

The XML functionality of SQL Server is vast, however, the best subset of that functionality that I've found may be demonstrated in the following example: Unfortunately, the example result is listed before the code. Join all the desired tables together Set the desired root element Set the path to an empty string to avoid an extra XML element at the root of each resulting row Provide an XPATH name with attributes for each of the desired columns (select * doesn't work well) Keep all the selected columns together by XPATH name or you'll split your xml attributes See my next blog entry for my best way to shred the xml
Read more

Brent: Programmer. Gamer. Cheapskate. All around good guy.

So... not being one that can leave a sore spot alone, when Brent Brown sent me an email Brent his "preferred" blog link so that I could update the link I had created to Stubenville , I naturally couldn't just update my previous blog entry. I needed to take the opportunity to pour lemon juice, salt, and vinegar into the wound until it became a pulp of agonized flesh. It may be because that's the way I am, but it may also be because Brent really needs this kind of opposition in his life. After all, he has a wonderful wife and cute kids, but as far as I can see, nobody that really gives him the harassing that he needs to keep his life in balance. That's where I come in. I don't know what the big deal is... after all, I liked the Stubenville (not Stupid-ville, that's a whole other wound that needs opening from time to time) thread. However, since he isn't there any more, I suppose that it has a limited shelf life. So, if anyone actualy reads my blog, you...
Read more