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Month: March 2016

Headless Pi: Using Xojo and Raspberry Pi Without a Display

You don’t need to hook up your Pi to a physical display, keyboard and mouse. You can set up VNC on the Pi so you can remotely connect to it.

My Raspberry Pi 2 sits on my desk next to one of my speakers. It’s not hooked up to any display. I use a combination of SSH, SFTP and VNC when I need to work with it.

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Houston, Here We Come: Things to Do, Eat and Visit in Space City

My family moved to Houston when I was 3 years old. Though my little sister cried for most of the cross-country road trip, my parents did not take my advice to leave her in Chicago and we all arrived in the Bayou City. I took up the cowgirl hat and any excuse I could to wear my boots with every outfit.


Visitors to Houston will find the city is served by 2 large, international airports (IAH & HOU), the restaurant scene is diverse and extensive, the city’s museums range from the acclaimed Children’s Museum to the beautiful Rothko Chapel, and the attractions of the surrounding area.

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Let’s Talk Office Ergonomics

If you work at a desk all day, you should be thinking about your ergonomics.

Being comfortable while you work is important. It enables you to concentrate better, but more critically, it prevents you from injuring yourself. From Musculoskeletal to vision and hearing problems, yes, it is quite possible to injure yourself while working at a desk!

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Easily Sorting Arrays of Classes

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.

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Raspberry Pi 3 Announced!

On 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!

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Sorry, You’ve Run Out of Memory

Most 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?

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How to Recursively Delete a Folder

While 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:

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