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How to add a 'Detect Key' Function
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Mr Kidnapper
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Default How to add a 'Detect Key' Function - 02-23-2011, 09:29 PM

In this post I will go into detail about Key events.. You don't actually know how useful they are until you're forced to use them, haha. For this function you are required to have prior knowledge of If/Else Booleans and average knowledge of how to read a screen. This event is useful for detecting beyond what the 'When a key is typed' event limits you to, such as F1, parentheses, Num Lock, as well as other basic keyboard functions. Alice does not detect the bells and whistles such as F Lock and customizable macro keys that most gaming keyboards and mice have.
Step 1: Create a 'When a key is typed' event and a world-level Number Variable set to whatever you want. I use 0 or 1. The number of the variable should have no conflicts if you're using it for the sole purpose of detecting keys.
Do not use any variable besides a Number Variable—it just doesn't work.
Step 2: Drag the Number Variable, which I named "Key Pressed" to the 'Do Nothing' portion of the event. When the dialog box pops up, make it Set to world.event.code. This is the first real step towards detecting any given key with Alice, taking no shortcuts.
It should say "When {any key} is typed, do {world.Key Pressed set value to code more...}"
You should no longer do anything to this event, it's complete. Right click the Key Pressed variable in the properties tab and click 'Watch This Variable.' This is so that when you Play the world, you can actually see what you're typing.

Now you have to actually make use of the detection.
Step 3: Create another Event, this time, you should have guessed it, When a Variable Changes. Set the variable in this event to Key Pressed.
Because the event (and hopefully all other subsequent events) only runs when Key Pressed is changed, you don't have any method conflicts. Of course, that assumes that the methods all use different keys. If two or more of them use the same key, then you have a problem on your head.
I should note that when doing this Event, you can choose either the Key Pressed variable or the world.event.code expression, however the first event must set the Key Pressed variable to world.event.code. I don't actually know why it doesn't work without that first requirement—it just doesn't.
Step 4: Create a Method. You surely had some objective in reading this far, but I will stick to something I have already done: A weapon change system.
http://img441.imageshack.us/img441/5023/21841405.png
As you can see, you can set the changed variable event to either code or Number Chosen. Also, there is quite a lot of If/Else and Booleans in there. They're in there for a reason. In the image, the numbers 49 and 35 stand for the number 1. 49 is the number 1 on top of WASD, and 35 is the number 1 on the Numpad. I simply made it possible to do both. If you know of a better way to do this that perhaps involves the For All In Order thing, let me know. I haven't much time to devote to this project lately.
TBA: Detect Code Keymap and Multiple Key Combinations

Last edited by Mr Kidnapper; 02-24-2011 at 07:51 PM.
   
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David B
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Default 02-24-2011, 03:17 PM

Could you make the photo smaller? I couldn't see what was written.


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