Help with init() and deinit() functions | Forex Factory

Options

Permalinks
Print Thread

Similar Threads

Can I get a little help with EA which includes many functions? 12 replies

deinit Indicator in MQL 1 reply

passing a varible between functions help 15 replies

File Functions help 0 replies

Can somebody help to add these functions to this EA 0 replies

Attachments: Help with init() and deinit() functions
Exit Attachments

Help with init() and deinit() functions

  • #1
  • First Post: Jun 29, 2008 11:10pm Jun 29, 2008 11:10pm
Hello,

I tried searching for a thread which would give answers to my questions but couldn't find any. I have had previous java coding experience but I am new to MT4.

I just reviewed the lessons by coder's guru. I had the following few questions as I start to code my first EA.


  1. what is the purpose of init() and deinit() function. If start does all the work, what's the reason for these two methods as I see them being completely blank in quite a few cases.

  2. Does every method have to have a return(0) statement? Like can we have void methods in MT4?

  3. Can an anyone please point me to a link where all the API of MT4 is written with all the constants and variables?






    Your help is GREATLY APPRECIATED.

Thanks .

  • #2
  • Jun 29, 2008 11:17pm Jun 29, 2008 11:17pm
Also, as a starting point to see if I am getting somewhere, in Java or C++, I would've started with printing "hello world" for the first run of my code, then run it in a loop......


Here I have no idea where and how to start when I am trying to learn MT4. I tried running the coder's guru ea from the lessons they have described and unfortunately, it didn't run (sad face on mt4 chart).

Can any experienced coders please point me into a direction as to where did they start from?


Thanks
  • #3
  • Jun 29, 2008 11:17pm Jun 29, 2008 11:17pm
init is only called on during the initial start of the indicator or EA OR when you switch timeframes.

deinit is only called on the removal of the indicator or EA or when you initially switch timeframes but before the new timeframe takes effect.

Yes, you can have functions without the return statement. You just need to specify the void.

And your last question, I only know of the help file for that info. It is a pretty comprehensive help system.
  • #4
  • Jun 29, 2008 11:20pm Jun 29, 2008 11:20pm
Quoting Svm
Also, as a starting point to see if I am getting somewhere, in Java or C++, I would've started with printing "hello world" for the first run of my code, then run it in a loop......


Here I have no idea where and how to start when I am trying to learn MT4. I tried running the coder's guru ea from the lessons they have described and unfortunately, it didn't run (sad face on mt4 chart).

Can any experienced coders please point me into a direction as to where did they start from?


Thanks
I would start by creating an indicator first. something simple like a moving average. This will break the ice with metatrader and its complete lack of debugging tools. Then move onto an ea which can get very complicated quickly.
  • #5
  • Jun 29, 2008 11:29pm Jun 29, 2008 11:29pm
This video by Patrick Nouvion is a great intro to MT4 programming.
Dave
  • #6
  • Jun 29, 2008 11:52pm Jun 29, 2008 11:52pm
Quoting magnumfreak
I would start by creating an indicator first. something simple like a moving average. This will break the ice with metatrader and its complete lack of debugging tools. Then move onto an ea which can get very complicated quickly.
Thank you so much magnumfreak for your responses.

So what kind of code/instructions would go into init() and deinit() functions?

Can anyone give me a sample code/instructions for these two methods?

As for help file, it hasn't been of much help to me as I couldn't find anything there. (Please see the attached picture).

There are a lot of keywords like Bars, close, OrderSelect, etc. I wanted some API for these reserve words.

Also, I'm still a little confused about how to work around/with bars.
Attached Image
  • #7
  • Jun 29, 2008 11:55pm Jun 29, 2008 11:55pm
Quoting DaveL
This video by Patrick Nouvion is a great intro to MT4 programming.


Is it a tutorial in flash? I tried loading it but it didn't work for me.?!??
  • #8
  • Jun 30, 2008 12:01am Jun 30, 2008 12:01am
typically init is just for things you want to execute just once upon starting. I use it for setting initial values for an indicator or ea. So, let's say you have different settings for an indicator based on the timeframe it is running on. I would detect the timeframe and set the values for those variables in the init function.

deinit I typically use for deleting objects from the chart. So if I needed a line for something in the chart for that timeframe and I wanted to delete it before moving on to the next I would do it in the deinit function.
  • #9
  • Jun 30, 2008 8:28am Jun 30, 2008 8:28am
Quoting Svm
Is it a tutorial in flash? I tried loading it but it didn't work for me.?!??
Yes, it is a Flash animation. You might try downloading the video directly, if your browser's doesn't have a Flash player.
Dave
  • #10
  • Jun 30, 2008 10:32am Jun 30, 2008 10:32am
Hello,
You could also start by looking at www.mql4.com . I just started learning mql4 too, and found the 'book' they have to be a helpful guide to learning the language. After that, I simply look up the 'documentation' section when I have some function or the other in mind to use.

Hope it helps,
Ravi
  • #11
  • Jun 30, 2008 1:10pm Jun 30, 2008 1:10pm
Quoting DaveL
Yes, it is a Flash animation. You might try downloading the video directly, if your browser's doesn't have a Flash player.
Using Firefox v3.0, I have a flash player, the page loads the player but stays blank. Several parts of the IBFX web site have this problem at the moment. The video works fine with Internet Explorer (at least for me). It is a good video.
  • #12
  • Last Post: Jun 30, 2008 2:27pm Jun 30, 2008 2:27pm
init is also called if the user changes the parameters.
0 traders viewing now