C / C++ / MFC

8-Jan-02 21:48

Hi ,
Guys need some info abt property pages.I need to develop an application with tabs.But the problem is that i don't know the number of tabs at design time.So am planning to use property sheet.But am not sure whether we can dynamically generate property pages and if i can do that then can i add few controls and caption to it also(dynamically).Am using VC++ 5.0 .
Thanks

vandana

James R. Twine9-Jan-02 2:39

James R. Twine

9-Jan-02 2:39

vandanakaul wrote:
But the problem is that i don't know the number of tabs at design time.

If you do know the maximum number of tabs/pages that will ever need to be created, you can do that easily. For example, if your application is a shareware application that will only show the last two Pages (Tabs) if it is registered, you can simply not call "AddPage(...)" for the last two pages if the app is not registered. It is easy to dynamically change the number of Pages/tabs in the Property Sheet.

Dynamically building a dialog template sounds a bit like overkill to me. Are you sure that is what you need to do? If so, someone else is gonna have to help you with that! Smile | :)

A possible solution is to have a "Generic" page that you can just change the caption, control text, show/hide controls, etc., and add that customized Page to the Property Sheet as needed.

Peace!

-=- James.

vandanakaul9-Jan-02 17:37

9-Jan-02 17:37

Hi,
Thanks for the reply but i guess i need to generate dialogs templete also dynamically.Since don't know the inital count of tabs i can not have dialog templetes made at design time.Do u know any better option except property pages .

Cheers

Vandana

James R. Twine10-Jan-02 6:37

James R. Twine

10-Jan-02 6:37

vandanakaul wrote:
Thanks for the reply but i guess i need to generate dialogs templete also dynamically.Since don't know the inital count of tabs i can not have dialog templetes made at design time.

   Is it not required that you have one unique dialog template per page/tab.

   For example, if your app had a "Tools" feature that the user could add tools to at runtime, you could add multiple copies of the same dialog template, one for each added tool.  And since the tools would all have some common items (Path, parameters, etc.), you could use a generic dialog template.

   Without knowing exactly what you are trying to use the other "dynamic" pages for, I can only be of limited assistance.

   Peace!

-=- James.

vandanakaul10-Jan-02 18:37

10-Jan-02 18:37

Hi ,
Seems i will get the solution this time Smile | :)

.Let me explain it a bit more.Can u just open the Options dialog in VC (TOOLs->Option) .I want something like this.Say "n" number of tabs with different caption(that of course labelled at runtime) .The look and feel of all Tabs (Dialog templates )will be same,that is they will all have the same controls and at same place.They will only differ in data .

Now can u help Smile | :)

Cheers

Vandana

James R. Twine11-Jan-02 18:55

James R. Twine

11-Jan-02 18:55

vandanakaul wrote:
The look and feel of all Tabs (Dialog templates )will be same,that is they will all have the same controls and at same place.They will only differ in data .

   That is exactly what I suggested as a solution previously:

>> A possible solution is to have a "Generic" page that you can just
>>change the caption, control text, show/hide controls, etc., and
>>add that customized Page to the Property Sheet as needed

   This is very easy to do.  Do you need help in implementing something like this?  All you need to do is construct/configure each of your 'n' pages (by creating an instance of the dialog class for each one), and call the Property Sheet's AddPage(...) method to add them in.

   Peace!

-=- James.

vandanakaul14-Jan-02 21:08

14-Jan-02 21:08

Hi,
How do i do it.Can u put in a sample for this.That will be great.Thanks for all your help and time Smile | :)

cheers

vandana

Working with CArray

8-Jan-02 21:16

Hi All,
Does following declaration part is legal:
struct SSingleData
{
CString csName;
CString csValue;
};

struct SDataRecord
{
CString csID;
CArray <ssingledata, ssingledata=""> DataArray;
};

CArray <sdatarecord, sdatarecord=""> m_SearchDataArray;

If yes then why I'm getting compilation error message at followint statment
m_SearchDataArray.Add(mySingleRecord);

mySingleRecord is type of SDataRecord

And Error is "error C2440: 'type cast' : cannot convert from 'struct SDataRecord' to 'struct SDataRecord'
No copy constructor available for struct 'SDataRecord'"

Thanks for Taking Time to write in.
Do I need to introduce constructor, where and how?
If my approach is wrong then please give me implementaion suggession for this problem.

--Sumit

Re: Working with CArray

Christian Graus8-Jan-02 22:17

Christian Graus

8-Jan-02 22:17

In order to put things in <>, like CArray<sdatarecord>, you need to check the box that says 'ignore HTML'. I presume that is what you had said though.

If you store records, not pointers to them, then your struct needs to provide a copy constructor so a copy can be made to put into the array - that is precisely what the error is telling you. Your choices are to store pointers to records ( or references, but then the objects being refered to also need to be in scope somewhere, so there's no point ), or write a copy constructor.

While we're at it, CArray is *rubbish*, you should be using std:vector, for more reasons than I can quickly enumerate.

Christian

I have come to clean zee pooollll. - Michael Martin Dec 30, 2001

Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now

Re: Working with CArray

Joaquín M López Muñoz8-Jan-02 22:46

Joaquín M López Muñoz

8-Jan-02 22:46

Your post is a little hard to understand due to the fact that you haven't selected the "Ignore HTML" check, as Christian pointed out.
You need to provide the three canonical ctors (default, copy and assignment, this latter is not technically a ctor, but works similarly) for SDataRecord:

struct SDataRecord{
    SDataRecord()
    {
    }

    SDataRecord(const SDataRecord& r):
        csID(r.csID)
    {
        DataArray.Copy(r.DataArray);
    }

    SDataRecord& operator=(const SDataRecord& r)
    {
        csID=r.csID;
        DataArray.Copy(r.DataArray);
        return *this;
    }

    CString	csID;
    CArray <SSingleData, SSingleData> DataArray;
};

Why is this so? Well, the discussion is a little technical, but I think you might find it worth knowing. In C++, if you don't provide a copy ctor (the same goes for the assignment operator), then the compiler makes up one for you automatically. This default copy ctor simply copies all the members of the class one by one (what's called memberwise copy): so it's easy to figure out how to copy members of built-in types line ints, pointers and the like. With respect of members of non-primitive types (classes), the compiler uses their respective copy ctors if available: again, these copy ctors can be explicitly defined by the programmer of automatically generated.
What's happening to your SDataRecord? When the compiler tries to generate its copy ctor, first it deals with csID, and finds no problem, then it tries to locate the copy ctor for DataArray, whose type is CArray <SSingleData, SSingleData>, but CArray does not have a copy ctor (it derives from CObject which explicitly forbids copying between its instances). Conclusion: SDataRecord does not get an automatically generated copy ctor, and it's your task to write it yourself (same for the operator asignment). Altough CArray does not have copy ctor, its member function Copy does the same job.
One more subtlety: Once you define any ctor, the compiler does not provide an automatic default (no arguments) for you (as it's the case in SSingleData, for instance), so you have to include the definition for the default ctor as well.

PS: I second Christian's suggestion about quitting MFC containers and using instead std::vector and its merry STL companions.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Saving CDC to Bmp File

Abhishek Narula8-Jan-02 20:25

Abhishek Narula

8-Jan-02 20:25

I have drawn some lines etc. on a CDC , now can I save this drawing to a Bmp File ?? How ?

Thanks in advance !

Abhishek Narula

"Learn to appreciate others ... World would appreciate you"

Rickard Andersson²⁰8-Jan-02 21:16

Rickard Andersson²⁰

8-Jan-02 21:16

Do you want to save a file (.bmp)?
If so, this question is very very very often shown here on the message board!

Try CXImage in the Bitmaps & Palettes section here on CodeProject!

------------------------------
©0d3 ©®4©k3® - That's me! Smile | :)

------------------------------

Christian Graus8-Jan-02 22:13

Christian Graus

8-Jan-02 22:13

You've actually drawn lines on a bitmap *selected* into a CDC, and has been pointed out, this question is addressed in the FAQ.

Christian

I have come to clean zee pooollll. - Michael Martin Dec 30, 2001

Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now

Abhishek Narula8-Jan-02 22:23

Abhishek Narula

8-Jan-02 22:23

Okay so you mean by GetCurrentBitmap() I ll get the bitmap of what ever is drawn on the screen ... so now how do i save this to a file ??

If you dont mind please give me the URL of FAQ , I am some what new to this Forum !
Regards,

Abhishek Narula

"Learn to appreciate others ... World would appreciate you"