Trying to understand PopUp Menus!

[Guido Meng]

Hi All!

I'm an amateur programmer and just recently came across a piece of code to build popup menus with the right-click of the mouse. It works!, I think I can adapt it and use it to enhance my own code however, since I don't fully understand how it works, I'd feel like the Apes in Planet of the apes when they pulled a car with horses not knowing any better . What I understand is this:

1) A bunch of functions (I think, pre-built for usage on almost any programming language) are used to build the menu, destroy it when no longer needed, etc.
2) There are other ways to build the PopUp menus, I think, but I'm not sure if they would be quiet as effective or at least as easy and flexible to use.
3) What really confuses me the most is the usage of things like: * <-----------------------

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MF_SEPARATOR = &H800& <---------- What is this? some sort of hexadecimal notation? what is it used for? is there any advantage for using this?

for any help or guidance Thanks a lot !



















Const MF_SEPARATOR = &H800&, then later a parameter in other words, why the need of constants instead of just

[Chippy]

Const MF_SEPARATOR = &H800&, then later a parameter in other words, why the need of constants instead of just

Instead of just what?

The &H prefix denotes a hexadecimal number. The & suffix is a type declaration character - http://support.microsoft.com/kb/191713 - and & denotes a Long constant, overriding the default Integer type for constants.

Hexadecimal notation makes it easier to see which bits of a flag or bitmask are set. For the AppendMenu function used in your code - http://msdn.microsoft.com/en-us/libr...=vs.85%29.aspx - the uFlags parameter is a 32-bit (4 byte) number and the values represent different bits, in sequence &H1, &H2, &H4, &H8, &H10, &H20, &H40, &H80, &H100, &H200, &H400, &H800, etc.

Constants make the code easier to read and understand. You can use the raw numbers (hex or decimal) instead of the constant names if you like, but then you might be wondering what &H800 (or 2048 decimal) means.

[Leith Ross]

Hello Guido Meng,

Here are some examples as to way naming a constant helps you understand the what is happening in the function. This is especially true with low level code like the API. Each of the constants has the same value but each has a different purpose depending on the function it is used in.

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[Guido Meng]

Thanks a lot for your comments Chippy!

I now realize that there're a LOT of things for me to learn yet when it comes to programming. I think I'll start with the links you sent me.

[Guido Meng]

Hi Leith Ross,

Thanks for the info.! I think I'll need to buy me some books on the whole programming subject hehehehe. I like it but back Highschool I just learned programming at a procedural level so, I guess I've a lot of updating to do.