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
BreakI 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
There aren’t a lot of items in a Xojo desktop project that you can’t rename. You can change the name of the App instance, the default window, the default menu bar and many many others.
But there are a handful that, if you do rename them, you may inadvertently break your application. This is entirely due to how the Xojo framework works, and in part how macOS itself works.… Read the rest
This looks like it could be a nice forum as a place to learn about and discuss cross-platform app development, not specifically focused on Xojo (although that will be one of the topics I’m sure)
As an alternative to the Xojo forums where you cannot discuss other products etc this one is focused on cross platform – regardless of toolset
I’ll give it a chance.… Read the rest
A small handful of changes in 2019r3.1
Module Color
alpha changed to Integer
Function CMY(cyan As Double, magenta As Double, yellow As Double, alpha As Integer = 0) As Color
ColorGroup
gained operator_compare
Function Operator_Compare(otherColor As Color) As Integer
Module Crypto
added PBKDF2 with HashAlgorithms parameter
Function PBKDF2(salt As String, data As MemoryBlock, iterations As Integer, desiredHashLength As Integer, hashAlgorithm As HashAlgorithms) As MemoryBlock
Class DatabaseColumn
now has a destructor
Sub Destructor()
Class DatabaseRow
added Column setter method
Sub Column(name As String, Assigns value As Variant)
added Destructor
Sub Destructor()
Module String
new overloads for IndexOf
Function IndexOf(Extends s As String, startPosition As Integer, searchString As String, options As ComparisonOptions = ComparisonOptions.CaseInsensitive,… Read the rest