C / C++ / MFC

Re: How do I access / use base class method declared private?

9-Mar-14 13:28

I like to use HitTest to identify a splitter pane via mouse.
It is a virtual function / method declared "protected" in base CSplitterWnd class.
I have never used this and have no idea what is the correct syntax.
I would appreciate any help.
Vaclav

Ok I build an override function with instance of base class, but still cannot figure out how to get pass the "protected" virtual function.

-- modified 9-Mar-14 20:16pm.

Richard Andrew x649-Mar-14 17:17

Richard Andrew x64

9-Mar-14 17:17

Isn't it:

C++

CSplitterWnd::HitTest(blah, blah);

The difficult we do right away...
...the impossible takes slightly longer.

Re: How do I access / use base class method declared private?

Vaclav_10-Mar-14 1:30

Re: How do I access / use base class method declared private?

10-Mar-14 1:30

Nope,
cannot access function declared protected.

Freak3010-Mar-14 2:21

Freak30

10-Mar-14 2:21

If you (publicly) derive from the base class, you should have access to all protected members of the base class from your derived class. So the start of your class definiton should look like

class MyClass : public CSplitterWnd

If you have a protected in this line instead of the public, it will not work. Also the access will only be available from your derived class, not from any other class that uses an instance of the derived class.

The good thing about pessimism is, that you are always either right or pleasently surprised.

Re: How do I access / use base class method declared private? SOLVED

Vaclav_10-Mar-14 10:26

Re: How do I access / use base class method declared private?

10-Mar-14 10:26

Thanks,
you found the problem. My splitter is derived from CMDIChildWnd.
I am not sure why, but it works as a splitter OK.
And since I am still using VC6.0 MFC multiple inheritance should work, but that is a ton of work to remove all the ambiguities...
I was going to use HitTest to maximize selected pane, so I better stick with moving splitter bars.

«_Superman_»10-Mar-14 5:21

«_Superman_»

10-Mar-14 5:21

HitTest is not a function that you call using the instance of a class.
Rather, it is a virtual function that you can override, so that the MFC framework can call it using a base class object reference.
There are other similar virtual functions like OnInitDialog for example.

From the HitTest override, you simply check the point passed in and return one of the HTXXX values.
For example, to move a dialog by clicking and dragging anywhere on it, just like its caption, you simply return HTCAPTION from the overridden HitTest method of the CDialog derived class.

This is how it will be called internally -

C++

// Imagine this to be the framework code
class CMyFramework
{
public:
    void foo() { this->bar(); }

protected:
    virtual void bar() { }
};

// Here are your overrides
class COne : public CMyFramework { };
class CTwo : public COne { };
// Derive to your hearts content like MFC does.

// Finally
class CTen : public CNine
{
protected:
    virtual void bar()
    {
        cout << "MyBar" << endl;
    }
};

The framework simply calls the CMyFramework::foo method and it will call CTen::bar because it is virtual.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++) (October 2009 - September 2013)

Polymorphism in C

modified 10-Mar-14 11:31am.

MDI frame "Window" menu / submenu dynamics - where to start?

Vaclav_9-Mar-14 5:07

Re: MDI frame "Window" menu / submenu dynamics - where to start?

9-Mar-14 5:07

Standard MFC MDI adds new view(s) to “Window” menu submenu.

Could someone give me a hint how is it accomplished when the application starts?

I am little familiar with dynamic menu / submenu operation but I cannot find how it gets started in creation of submenu under “Window” menu item. I did not get very far tracing the creation of the main frame.

Any help will be as always appreciated.
Cheers

Richard MacCutchan9-Mar-14 8:11

Re: MDI frame "Window" menu / submenu dynamics - where to start?

9-Mar-14 8:11

It uses CMenu::InsertMenuItem[^]. MDI is now largely deprecated in favour of CTabbedPane[^].

Vaclav_9-Mar-14 13:20

Re: MDI frame "Window" menu / submenu dynamics - where to start?

9-Mar-14 13:20

Thanks Richard,
I know about InsertMenuItem, I was looking for where in the initial setup is it used and I found it.
As far as CTabbedPane I have made two decisions - if I get an income from my programming hobby I'll spring for the latest MS VS or I'll ditch my VC6.0 and start over using Linux.
Just for illustration - I did checked MS site for "2013 requirements" and my IE locked up. Unless I am wrong - MS express / semifree stuff does not come with MFC.

Richard MacCutchan9-Mar-14 22:16

Re: MDI frame "Window" menu / submenu dynamics - where to start?

9-Mar-14 22:16

True, MFC is not provided free with the Express editions. However, if you decide to switch to C# you get the complete .NET development library, which provides everything that MFC does, and more.

Vaclav_10-Mar-14 1:35

Re: MDI frame "Window" menu / submenu dynamics - where to start?

10-Mar-14 1:35

But ... don't I have to "upgrade" to windows x.y to keep the .NET current? If so it is still spending $ on this hobby which I could use on bying beer.

Richard MacCutchan10-Mar-14 1:53

WM_GETTEXT does not returns data from Grid Control of external application

10-Mar-14 1:53

Your choice, of course. Stick with whichever technology you prefer.

CMap efficiency

econy7-Mar-14 5:20

econy

7-Mar-14 5:20

Hi, if Key-Value pairs are like:

40000   "40000 is a first number"
41020   "41020 is a second number"
....

use CMapStringToString or CMap<int,int,string,string> to store.

Then which one is better in look up efficiency?

CMapStringToString　ｏｒ　CMap<int,int,string,string>

Re: CMap efficiency

jeron17-Mar-14 5:48

jeron1

7-Mar-14 5:48

econy wrote:
Then which one is better in look up efficiency?

I don't know, but I cannot imagine having to convert between ints and CStrings just to use the CMapStringToString could possibly be worth it, I would start with the CMap.

Re: CMap efficiency

CPallini9-Mar-14 4:57

CPallini

9-Mar-14 4:57

Why don't you test that?

Veni, vidi, vici.

Re: CMap efficiency

Stefan_Lang12-Mar-14 1:29

Stefan_Lang

12-Mar-14 1:29

Lookup requires comparing keys, i. e. calling the operator < and maybe operator ==. Since these operators are more efficient for ints than they are for strings, I suspect that CMap is better. However, the rest of the looking-up algorithm that does not involve comparing keys may play a much more significant role on performance overall, so you might not notice a difference.

You should also consider whether there are other operations than looking up which are called often, e. g. insertion, removal, converting keys to different formats, etc.: E. g. if you spend a lot of time reading keys from a text source or writing them as text, then it may be advisable to just stick with string keys rather than converting them back and forth all the time!

GOTOs are a bit like wire coat hangers: they tend to breed in the darkness, such that where there once were few, eventually there are many, and the program's architecture collapses beneath them. (Fran Poretto)

Point in case: http://www.infoq.com/news/2014/02/apple_gotofail_lessons[^]

pandit847-Mar-14 4:33

pandit84

7-Mar-14 4:33

Hi
I got handle to Grid Control of window of another ( external ) application. Used EnumChildWindows for getting child window handle.
But I am unable to read text from that grid control.
Can anyone provide any pointers for this ? Thanks in Advance.

Re: WM_GETTEXT does not returns data from Grid Control of external application

Richard MacCutchan7-Mar-14 5:54

Auto align of toolbar by frame width

7-Mar-14 5:54

The WM_GETTEXT message will only return the text of the window whose handle you provide. It will not include the content of child windows, as exist in a grid control.

akhil_sudheesh6-Mar-14 19:44

akhil_sudheesh

6-Mar-14 19:44

Hi, am building a GUI MFC application, I have several toolbars in my application, i want my toolbars to auto align according to my application frame width, the code i have been tried is given below. By this code the toolbar is simply align in a single row. what should i do to reach my goal? Confused | :confused:

thanks in advance

m_wndMenuBar.EnableDocking(CBRS_ALIGN_ANY);
    tb1.EnableDocking(CBRS_ALIGN_ANY);
    m_wndToolBar.EnableDocking(CBRS_ALIGN_ANY);
    tb4.EnableDocking(CBRS_ALIGN_ANY);
    tb8.EnableDocking(CBRS_ALIGN_ANY);
    tb9.EnableDocking(CBRS_ALIGN_ANY);
    tb2.EnableDocking(CBRS_ALIGN_ANY);
    tb3.EnableDocking(CBRS_ALIGN_ANY);
    tb6.EnableDocking(CBRS_ALIGN_ANY);
    tb7.EnableDocki:confused:ng(CBRS_ALIGN_ANY);

    EnableDocking(CBRS_ALIGN_ANY);

    DockPane(&m_wndMenuBar);
    DockPane(&tb9);
    DockPaneLeftOf(&tb8, &tb9);
    DockPaneLeftOf(&tb4, &tb8);
    DockPaneLeftOf(&m_wndToolBar, &tb4);
    DockPaneLeftOf(&tb1, &m_wndToolBar);
    DockPaneLeftOf(&tb7, &tb1);
    DockPaneLeftOf(&tb6, &tb7);
    DockPaneLeftOf(&tb3, &tb6);
    DockPaneLeftOf(&tb2, &tb3);

A learner

Rage12-Mar-14 22:15

Rage

12-Mar-14 22:15

Your intention is not totally clear, can you try and explain better what you are trying to do and what is not working ?

~RaGE();

I think words like 'destiny' are a way of trying to find order where none exists. - Christian Graus
Entropy isn't what is used to.

akhil_sudheesh13-Mar-14 19:55

akhil_sudheesh

13-Mar-14 19:55

Hi, thanks for the replay, my program consist of 9 toolbars of which different length, when i arrange my toolbars it appearing on a single row, so some of my toolbars are not visible am sharing a screen shot with this replay the first image shows how toolbar appears when i build the application, the 2nd image shows my requirement

https://plus.google.com/photos/108871638000088451495/albums/5990517728523218353?authkey=COPXvr6RjcCABQ[^]

hope you understand my requirement thank you

A learner

Rage14-Mar-14 0:07

Rage

14-Mar-14 0:07

OK, I see. Can you fish something out of this code sample :
http://msdn.microsoft.com/en-us/library/bb983325%28v=vs.90%29.aspx[^]

~RaGE();

I think words like 'destiny' are a way of trying to find order where none exists. - Christian Graus
Entropy isn't what it used to.

Rage14-Mar-14 0:15

Rage

14-Mar-14 0:15

Another comment:
Is your toolbar CMFCToolbar ?

From MSDN: http://msdn.microsoft.com/en-us/library/cc665920.aspx[^]

This method (EnableDocking) extends the base class implementation, CBasePane::EnableDocking, by setting the CBasePane::m_dwControlBarStyle data member to AFX_CBRS_FLOAT. This method then passes dwAlignment to the base class implementation.

Maybe you would need the AFX_CBRS_RESIZE as well, see here in the base class:
http://msdn.microsoft.com/en-us/library/cc701911.aspx[^]

~RaGE();

I think words like 'destiny' are a way of trying to find order where none exists. - Christian Graus
Entropy isn't what it used to.