Thread: HELP!! Urgent !!

Hi, can anyone help me ? i dunno how to solve this. Pls help.
Please follow the step to reach the Question.
Thanks a lot!!!

Code:

Step (1): Type structure definition

typedef struct menu_item_struct
{
	  ros_data_hdr_t            data_hdr;       /* place holder for ros header */
	  struct menu_item_struct   *next_item;     /* next menu item in the list */
	  UINT8                     position;       /* menu item position */
	   struct
	  {
	    uniChar_t               uniString[1];   /* place holder for string of Unicode characters */
	    UINT8                   asciiString[1]; /* place holder for string of ASCII characters */
	  } text;
} menu_item_t;


typedef struct
{
	  UINT8 row;                     /* start row for menu */
	  UINT8 max_item;                /* largest menu item position */
	  menu_item_t *first_menu_item;  /* pointer to the first menu item in the list */
} menu_item_list_t;



Step (2): Global variables declaration

menu_item_t * * m_menuitem;
UINT8 index=0;



Step (3): 

void setMenuItems( UINT8 index, menu_item_t * menu_item )
{

	m_menuitem[index] = menu_item;
	
}
//First, assume that the above "setMenuItems" was called for 5 times. Therefore, m_menuitem[] should have 5 elements now, and index has been incremented to 5.



Step (4):
//After that, assume that "process_menuItemfunc()" is called. At this point, m_menuitem[]contains 5 items.

void process_menuItemfunc()
{

   //In this function, I have to call "putMenu(menuItem_t *menuItemPtr, uint8_t num_of_items)" as defined below.
   //Notice that the 1st parameter of the "putMenu()" is a pointer to an array of menu items to be displayed.
   //The menu item is of class "menuItem_t" as defined below.
   
   //So, before I could call "putMenu", I have to populate the 1st parameters. Because the "m_menuitem" and "menuItem_t" are of different types.
   //Therefore, I cannot pass in "m_menuitem" directly to "putMenu()" as its 1st parameter.
   
   //QUESTION : How to populate/construct the 1st parameter, which is the pointer to an array of menu items of class menuItem_t?
                
   

}



//A class called menuItem_t is defined as below
class menuItem_t {

public:
        UINT8 position;
        UINT16 state;
        UINT16 *uniString;
  
};


//*menuItemPtr - This is a pointer to an array of menu items to be displayed. 
void putMenu (menuItem_t *menuItemPtr, UINT8 num_of_items)
{
   //some processing here
}

From the announcements:

3. Do not put URGENT!, or NEED HELP NOW, etc. in your title; it will not make people look at it any faster. Doing this makes many old time helpers on this board not look at the post at all.

Please follow the step to reach the Question.

Doesn't one usually follow the steps of a question to reach an answer, not the other way around?

Assuming that UINT8 is an integer type, probably something like this,

Code:

typedef unsigned char UINT8;

Then this function cannot modify index:

Code:

void setMenuItems( UINT8 index, menu_item_t * menu_item )
{

	m_menuitem[index] = menu_item;
	
}
//First, assume that the above "setMenuItems" was called for 5 times. Therefore, m_menuitem[] should have 5 elements now, and index has been incremented to 5.

Which means that the calling function must modify index, which makes that function pretty much useless. Besides, index is global, isn't it?

That function wouldn't even work unless the calling function also allocated some memory.

Code:

//A class called menuItem_t is defined as below
class menuItem_t {

public:
        UINT8 position;
        UINT16 state;
        UINT16 *uniString;
  
};

That might as well be a struct.

What I actually want to know is, the above "setMenuItems" was called for 5 times. Therefore, m_menuitem[] should have 5 elements now, and index has been incremented to 5. Am I right?
So, what actually contain inside the "m_menuitem[]" now are the 5 pointers to "menu_item_t". Am I right?

Yes, assuming the calling function handled a few things properly, like making sure that enough memory was allocated, and index was incremented.

I have "m_menuitem" now. You can see the 1st parameter from this function "putMenu (menuItem_t *menuItemPtr, UINT8 num_of_items)", it actually request a pointer to an array of type "menuItem_t, am I right?

So, I need to construct or get this pointer to an array of type "menuItem_t" from "m_menuitem". My question is how to do so? I don't know how to construct it so that I could pass it to "putMenu(..)" for further processing.

So basically your problem simplifies down to converting this

Code:

typedef struct menu_item_struct
{
	  ros_data_hdr_t            data_hdr;       /* place holder for ros header */
	  struct menu_item_struct   *next_item;     /* next menu item in the list */
	  UINT8                     position;       /* menu item position */
	   struct
	  {
	    uniChar_t               uniString[1];   /* place holder for string of Unicode characters */
	    UINT8                   asciiString[1]; /* place holder for string of ASCII characters */
	  } text;
} menu_item_t;

menu_item_t * * m_menuitem;

to this:

Code:

class menuItem_t {

public:
        UINT8 position;
        UINT16 state;
        UINT16 *uniString;
  
};


//*menuItemPtr - This is a pointer to an array of menu items to be displayed. 
void putMenu (menuItem_t *menuItemPtr, UINT8 num_of_items)

Is that right?

Well, you'll probably need a conversion function of some kind. Perhaps the best way to implement this would be to create a menuItem_t(menu_item_t&) constructor. Something like this.

Code:

class menuItem_t {
public:
        UINT8 position;
        UINT16 state;
        UINT16 *uniString;

        menuItem_t(menu_item_t &other);
};

menuItem_t::menuItem_t(menu_item_t &other) {
    position = other.position;
}

I don't know how you'd create the state and uniString members of menuItem_t out of the members of menu_item_t, but however you do it, do it in that function, in the same place I set position.

(To other C++ programmers: I didn't feel like explaining initializers.)

Using constructors is very easy. You can basically do this:

Code:

menu_item_t from;
menuItem_t to = from;
// now you have to

BTW, try to make your variable and type names different. If two variables are different but you pronounce them the same way (or nearly so), then consider renaming them.

In C++, you can have constructors in structs as well. But perhaps the best thing to do would be to have a conversion function.

Code:

menuItem_t convert(menu_item_t &other) {
    menuItem_t m;
    m.position = other.position;
    return m;
}

Something like that.

Lazy bastard. Ask questions, but do not ask us to do the whole damn job for you.

While your waiting for him to write the code, *cough*. You could read the rules perhaps?

Mmm, that makes more sense. With the [5] declaration your program doesn't have to mess around with dynamic memory allocation.

Tell whoever wrote that code that they should think up some better names.

Anyway, good luck.

And where do you compile the second line?