I recently had someone ask me how to reorder the columns in a SQLite table. As you may be aware, the SQLite ALTER table does not have a lot of functionality compared to other databases and it certainly doesn’t have a way to do this.
Comments closedYear: 2016
Sometimes you’re going to need a data structure that is an array of classes and you’re going to want to sort them. The standard array Sort method can only sort simple types (Text, Integer, etc), so what do you do?
The traditional technique has been to use SortWith. You create a separate array of a simple type, populate it and then sort the temporary array using SortWith to sort the class array.
But there is an even slicker way to sort that was added in 2015 Release 3. You can now create your own custom comparison method and use that to sort the class. This custom method returns 0 if the values to compare are equal, a positive if the first value is greater than the second, and a negative value if the first value is less than the second.
Comments closedOn Monday February 29th, the Raspberry Pi Foundation announced the new Raspberry Pi 3. This updated Pi has some significant improvements over the Pi 2, including:
- A 1.2GHz 64-bit quad-core ARM Cortex-A53 CPU (~10x the performance of Raspberry Pi 1)
- Integrated 802.11n wireless LAN and Bluetooth 4.1
- Complete compatibility with Raspberry Pi 1 and 2
That last bullet point is notable because it means that Xojo is also fully compatible with the new Raspberry Pi 3!
Comments closedMost of us build apps without thinking too much about how much memory the app will need. Sure sometimes you end up creating an app that is a real memory buster but that’s unusual. With virtual memory, gone are the days when your app would just run out of memory and crash, or are they?
Comments closedWhile Xojo doesn’t currently provide a direct way of recursively deleting a folder, there are various options that will allow you to do this:
1. Recursively iterate through all the folders, deleting each one. You can read about that at our Developer Site, this is the best cross-platform way.
2. Use the Shell to recursively delete a folder (i.e. “del /s” on Windows, or “rm -rf” on OS X and Linux)
Windows specific ways:
3. SHFileOperation (an older API)
4. IFileOperation (the more modern API that Windows recommends over option #3)
I’ve decided to look at option #4, since this allows more customized options, like the ability to show a progress dialog. However, it is also the slightly more complicated option since it deals with COM & Delegates. The example illustrates this:
Comments closedPaul talks with Tim Parnell, creator of several Xojo add-ons and active Xojo forum contributor.
To listen to this podcast, download the mp3 now.
Comments closedMaybe you’ve heard the term SQL injection and how it can allow unintended database access. Here’s how a SQL Injection works and what you can do to avoid it.
1 CommentA couple years ago I wrote a post about Going Rogue with Xojo. It proved to be rather popular and I got some great stories back from how people were able to use Xojo in their organizations.
Comments closedHow do you format and organize your code? I’m here to tell you that your way is wrong and my way is right 🙂
Comments closedIn the blog post Smartphone Encryption is a Red Herring, I pointed out the folly of requiring an encryption back door for the Good Guys to use. So the question arises- “What can be done? If we don’t want a global encryption back door that can be used by anyone, can we still track the Bad Guys?”
The answer is yes. There are plenty of options that don’t require a global back door. I’m not passing judgment on whether these are inherently good or bad options, just that they are available when there is a reason to track a Bad Guy.
Comments closed