Author: Norman Palardy

In 2019r3 Xojo added something that a lot of people have been asking for for a very long time. A way for a class that exposes events to know IF an instance implements the event.

Its literally called IsEventImplemented (see http://feedback.xojo.com/case/58342)

But it remains undocumented

Previously if you wrote a class that could have some default behaviour IF an instance did not implemnent the event to alter the behaviour you had no way to know if you should operate in whatever way was the default or not.… Read the rest

And by that no I don’t mean that YOU personally should fail. I’m of the same mind as my dad on that front. You should work your ass off to do the best job you know how to do. That doesn’t mean you’re perfect or that you expect perfection. There are lots of things in this world that I do not know how to do very well – but when given the opportunity I try to do the very best job I know how to and I try to learn how to do it better next time.… Read the rest

and other cruft starts to accumulate if you’re not careful. But thats not what this post is about.

Its literally about the programming language Rust.

It’s been quite some time since I’ve had to do a lot in C which is what Rust feels like. Full of curly braces and semicolons its VERY C like – and I’ll post about my adventures getting familiar with it and how I think it can be leveraged in a cross platform world.… Read the rest

Got a curious question the other day. One I had never really thought much about but after a discussion it became clear to me why the questions were the way they were.

Bit flipping and bit masking is not intuitive.

And unless you’ve had to do it then approaching it for the first time may no make a pile of sense.… Read the rest

Lately I’d been hanging out on some alternative Xojo discussion venues.

The one I’m finding useful is IfNotNil as they permit discussions of ANY topics which lead to cross platform development. So you can talk about Rust, Go, B4X products, LiveCode, Web and other toolsets you might use for cross platform software development.

Most of the time when we talk about events the first thing that pops into someones head isa UI control and the events is has for interaction with the user. A pushbuttons Action (or Pressed) event for instance. Or the various events on listboxes for selecting rows, handling mouse clicks, keyboard events and the myriad of other user interface and interaction related things listboxes handle.… Read the rest

Xojo now generally uses exceptions to handle errors.

And with that comes some things you should know about how exceptions work that you need to be aware of before you cause yourself problems.

First off, in my opinion, you should put your try catch blocks as close to the code that causes the error. While Xojo lets you use one EXCEPTION or CATCH block at the end of any method like the following

// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 
// do a bunch of code 


Catch foo As RuntimeException // or Exception foo as RuntimeException
Break

I would suggest you avoid this form.… Read the rest

Bit shifting can be troublesome. Especially if you’re not sure WHY they can be troublesome.

So some recommend only using UNSIGNED integers for such operations. And using *2 and \2 to do bit shifting.

At a very low level most modern CPUs implement certain numerical standards in various instructions. And, of note, nearly every last one has two (or more) forms of shifts.… Read the rest

Had an interesting discussion the other day and in the course of the discussion the use of prepared statements came up. Turned out that a few people had never used them and did all the leg work to created their own mechanism to concatenate strings.

For a long time in REALbasic. and REALStudio this was a requirement.… Read the rest

Xojo’s BIN, HEX and OCT methods and their new counterparts, ToBinary, ToHex, and ToOctal should do a better job than they do.

If you pass in an 8 bit value you _may_ get an 8 bit binary representation back – or not. And this is true for ALL numeric types. The string you get back may not represent the full value esp if the upper bits are 0.… Read the rest