I use a CArray<CClase1,CClase1> m_Clases1.
CClase1 is derived of CObject. " class CClase1 : public CObject"
When, at last I do : "m_Clases1.RemoveAll()" , I suppose that the CClase1 destructor is called. But when i do this the program fails.
I've created a base DLL for all my future DLL's, a way of getting version numbers and such and that compiles fine, but I can't add it into a class for a new DLL. All the headers do have an appropriate cpp to define the function declarations (and they compile fine).
All for the base DLL I have:
LibVer.h
Version.cpp
Function.cpp
LibVer.h
#pragma once
#include <vector>
#define DLLEXPORT 1
#define DLLIMPORT 2
#define DLL DLLIMPORT
[Code] .....
As long as no base class constructor takes any arguments, the derived class need not have any constructor, if one or more arguments are used then it is mandatory for the derived class to have a constructor and pass the arguments to base class constructors. While applying inheritance, we usually create objects using derived class. Then it makes sense for the derived class to pass arguments to the base class constructor. When both the base and derived class contain constructors ,the base class constructor is execute first.
In case of multiple inheritance, the base classes are constructed ,in the order in which they appear in the declaration of the derived class. Similarly in a multiple inheritance the constructors will be executed in order of inheritance. Since the derived class takes the responsibility to supply initial values to the base class,we supply the initial values that are required by all the classes together where the derived class object is declared.
The constructor of the derived class receives the entire list of values of arguments and pass them on to the base constructors int the order in which they are declared in the derived class
Is it possible to overload a variable in a derived class? Example:
struct Circle
{
int radius() const { return r; }
private:
int r;
}
struct Smiley : Circle
{
// inherits the function int radius() const, but doesn't return Smiley::r
private:
int r;
}
Code:
class Var {
public:
Var();
~Var();
private:
QMap<QString, QSharedPointer<Data>> _mapVars;
};
QDataStream &operator<<(QDataStream &stream, const QSharedPointer<Data> p_data);
QDataStream &operator>>(QDataStream &stream, Data &p_data)
I want to serialize _mapVars into a file. However, I have many other classes that are derived from Data, do i need to check for Data type inside the overloaded << functions like below in order to serialize ??? This doesn';t seem to be very correct ...
Code:
QDataStream &operator<<(QDataStream &stream, const QSharedPointer<Data> p_data) {
if(p_data->GetType == .....) {
}
}
S I want to have different >> operators for several derived classes. Has I tested...
Code: class base{
friend std::istream & operator>>(std::istream & in, base & v);
public:
base();
[Code]......
I noticed that the base operator is the only one being called for all 3 objects. which makes sense and now that I think about it I am more surprised that the "derived operators" compiled at all.
Still, how would I go about declaring different overloaded operators for the different classes?
class A {
// is abstract
};
class B : public A {
// ...
};
[Code] ....
[Code] ....
main3.cpp: In member function ‘FooB& FooB::operator=(const FooC&)’:
main3.cpp:46:44: error: expected ‘(’ before ‘other’
main3.cpp:46:49: error: no matching function for call to ‘Foo<C>::Foo(const FooC&)’
main3.cpp:46:49: note: candidates are:
main3.cpp:19:2: note: Foo<T>::Foo() [with T = C]
main3.cpp:19:2: note: candidate expects 0 arguments, 1 provided
main3.cpp:16:25: note: Foo<C>::Foo(const Foo<C>&)
main3.cpp:16:25: note: no known conversion for argument 1 from ‘const FooC’ to ‘const Foo<C>&’
Is there any way to make it work?
I need to access the functions of the derived classes from a vector of objects of base classes (can't believe I wrote it). Here a Diagram for you to understand:
So as you see, I need the function Use() from the Usable class, to be able to be called from the vector like:
inventory.at(x)->Use()
how to create a base class that is derived (inherited) by three other classes?
View 12 Replies View RelatedI am trying to build a destructor that takes an array pointer and outputs part of a private vector and, comparing a string within the objects, overwrites the data in the array with the data in the vector. (vector and array use same class type) It then proceeds as usual.
#include <iostream>
#include <string>
#include <iomanip>
[Code].....
I need to create an object of a mfc derived CFormView class that's not in the doc/template (a second view class). But it was generated with a protected ctor. Here's the code explanation with comments.
I'm thinking all the normal classes of the Doc/View template are created starting with this code, but within the template code base.
Code:
CSingleDocTemplate* pDocTemplate;
pDocTemplate = new CSingleDocTemplate(IDR_MAINFRAME,
RUNTIME_CLASS(CViewSwitchDoc), //<-expands to-> ((CRuntimeClass*)(&CViewSwitchDoc::classCViewSwitchDoc)),
RUNTIME_CLASS(CMainFrame), // main SDI frame window
RUNTIME_CLASS(CViewSwitchView));
But I have generated "another view" using the "Add Class" Wizard, it's a derived class of mfc CFormView which I named ViewForm. However I'm having a problem creating an instance of it because of the generated protected ctor and pulls a compile error of not being able to access ctor. Below are the header and implementation files of this said ViewForm class. How to create an object of this view ? Did I go about it all the wrong way since it's not in the doc/template group ?
// ViewForm.h file
#pragma once
// ViewForm form view
class ViewForm : public CFormView {
DECLARE_DYNCREATE(ViewForm)
[Code] ....
In my class:
Code:
class SettingsDialog : public CDialogEx
I have:
Code:
enum { IDD = IDD_SETTINGS_DIALOG };
I have a very similar dialog called IDD_SETTINGS2_DIALOG with all the exact same variables. Is it possible to conditionally load either of those dialogs in that class through a variable pass into the constructor? If so, how do I edit that enum type to add both?
I can't get tooltips to show up for the windows I want in my CFormView derived class. I have copied the code from the MSDN entry on EnableToolTips(). But only two windows respond with a tooltip:
CONTROL "Tree1",IDC_TESTPLANS,"SysTreeView32",TVS_HASBUTTONS | TVS_HASLINES | TVS_EDITLABELS | TVS_SHOWSELALWAYS | WS_BORDER | WS_HSCROLL | WS_TABSTOP,1,36,85,91
CONTROL "Tab1",IDC_TABCMD,"SysTabControl32",0x0,101,0,239,181
Other windows do not respond. For these windows my function designed to catch the TTN_NEEDTEXTW and TTN_NEEDTEXTA messages is not called. Windows such as
LISTBOX IDC_TESTPLANNAMES,0,119,48,40,LBS_SORT | LBS_NOINTEGRALHEIGHT | WS_VSCROLL | WS_TABSTOP
PUSHBUTTON "",IDC_BTN_COPY,105,177,24,24,BS_ICON
Why wouldn't the messages be sent for those windows? I'm using the code
ON_NOTIFY_EX_RANGE(TTN_NEEDTEXTW, 0, 0xFFFF, &CCntlrView::OnTtnNeedText)
ON_NOTIFY_EX_RANGE(TTN_NEEDTEXTA, 0, 0xFFFF, &CCntlrView::OnTtnNeedText)
(CCntrlView is the name of my class derived from CFormView.) And as I pointed out, I'm using the code straight from the example given in MSDN for CWnd::EnableToolTips(), with the only difference being that all my controls are created in the rc file as shown above.
This refers to an ATL COM DLL project. I can successfully create a class hierarchy of objects, ie. say, one class is the TEAM, which then holds other objects, say, a leader and a secretary, both of which are Employee Classes . Here goes my question:
a) In the Team.h header file I declare m_pLeader as a CComPtr<IEmployee>
Code:
classATL_NO_VTABLE CTeam :
public CComObjectRootEx<CComSingleThreadModel>,
public CComCoClass<CTeam, &CLSID_Team>,
public IDispatchImpl<ITeam, &IID_ITeam, &LIBID_BUOBJ05Lib, /*wMajor =*/ 1, /*wMinor =*/ 0>
{
private:
CComPtr<IEmployee> m_pLeader;
CComPtr<IEmployee> m_pSecretary;
b) The Employee Class is defined within this ATL COM project.
c) In the Team.cpp file, I create an instance in the FinalConstruct code, the focus is on the CEmployee
Code:
HRESULT CTeam::FinalConstruct(){
CComObject<CEmployee>* pLeader;
HRESULT hr=CComObject<CEmployee>::CreateInstance(&pLeader);
if (FAILED(hr))
return hr;
m_pLeader=pLeader;
// ..same for secretary...
return S_OK
}
d) Here comes my QUESTION: How must I proceed if the Employee object was part of another ATL COM DLL, that is it would be described in another DLL that I would now like to reuse? I guess I need to
1. Have the other DLL's idl-, tlb, and h file in my project folder. Let me name it "other.h, other.idl, other.tlb"
2. Both h- and cpp-file must have an #include "other.h" statement -- please correct if I am wrong..
3. ...but how must in the Team's h- and cpp-files the statements be (assuming the class in the "other" Dll is Member (instead of Employee? I know the following code will NOT work, so I am asking how it should be correctly?
Code:
private:
CComPtr<IMember> m_pLeader;
4. and in cpp file for:
Code:
CComObject<CMember>* pLeader;
HRESULT hr=CComObject<CMember>::CreateInstance(&pLeader);
[/code]
I'm am having a few issues with this program, they stem from passing the color.h and .cpp into another .h and .cpp, and frankly getting how those two things really fit together.
For this problem, you will design and implement 2 classes and then write a driver function to test these classes. The first will be a C++ class for an abstract data type color with a public enumeration type colorType that has the color values shown in Listing 10.8. Your abstract data type should have an attribute for storing a single value of type colortype and member functions for reading (readColor) and writing (writeColor) a color value as well as setting and accessing it. The function readColor should read a color as a string and store the corresponding color value in the value attribute of a type color object. The function writeColor should display as a string the value stored in the value attribute of a type color object (see Figure 7.5). Modify class circle and the driver function in Listing 10.9 to include and use this class. You'll need to remove the declaration for color in class circle. Test your modified driver function with the new color and circle classes.
The second class will be to design and implement a rectangle class similar to class circle. Be sure to incorporate the new color class you have written and tested in the first part of the programming exercise. Write a client program that asks the user to enter a shape name (circle or rectangle) and then asks the user for the necessary data for an object of that class. The program should create the object and display all its attributes.
The circle class .h and .cpp files as well as the original driver function will be supplied. You are to provide the .h and .cpp files for the new color class and the modified driver function as well as the .h and .cpp files for the rectangle class and the client program that uses all three classes.
color.h
Code:
//color.h
//Color class definition
#include "stdafx.h"
#ifndef COLOR_H
[Code].....
I am struggling to enable friendship between two classes in separate header files for a banking program.
I am attempting to get the Person class to use variables from the Account class. Heres what I have so far.
ACCOUNT.h:
Code:
#include<iostream>
#include<fstream>
#include<cctype>
#include<iomanip>
#include <string>
#include <math.h>
#include <windows.h>
#include <vector>
#include "Person.h"
using namespace std;
class person;
[code].....
The Light and Fan are two different vendor classes and they are not derived from any base class. I am trying to implement the Command design pattern but with generic implementation, so it should work in future with any new vendor class like Door, Window etc without much change in client code. I have thought about a Factory method but it will not work because it needs a Base class. I am trying to learn the design patterns.
Light *myobj;
Fan *myobj;
int choice;
cout<<"Select Light (1): ";
cout<<"Select Fan (2): ";
[Code] ....
Error:conflicting declaration 'Fan*myobj'
I have an array of (Student)classes created in Manager.h, which contains a new instance of class Name (name),(in Student.h)How would I go about accessing the SetFirstName method in Name.cpp if I was in a class Manager.cpp? I have tried using Students[i].name.SetFirstName("name");
// In Manager.h
#include"Student.h"
class Manager
{
[Code]....
I want write my first application using Xamarin Studio and GTK#.
I create new file Dialog.cs: public partial class Dialog : Gtk.Dialog
I add Fixed container and can't add buttons, why?
I must use class Window : Gtk.Window instead of Dialog and show modal this window?
I'm trying to call a function on a derived class that's in a vector of it's base class. I've made the code really simple for illustration purposes:
class Sprite {
virtual void update();
}
class Enemy : public Sprite {
virtual void update();
[Code] ....
I want to be able to just call update() on the items in the vector and the derived class update() functions be called. Currently, it always calls the Sprite update, which makes sense, but it's not what I want. Is there a way to call the derived update function without knowing the type of the derived class?
I dont know what kind of return reference I have to put to override the following derived member function in C++:
virtual SEntityPhysicalizeParams& GetPhysicsParams() override {return ???;}
The place where I should put the return value is marked with ???. SEntityPhysicalizeParams is a struct from another header from which I dont have access to it's source file.
I tried several things but noone seemed to work out and keep getting me either error "function must return a value" or "initial value of reference to non-const must be an lValue".
Here is SEntityPhysicalize where my function is refering to:
struct SEntityPhysicalizeParams
{///////////////////////////////////////////////////////////////////
SEntityPhysicalizeParams() : type(0),density(-1),mass(-1),nSlot(-1),nFlagsOR(0),nFlagsAND(UINT_MAX),
pAttachToEntity(NULL),nAttachToPart(-1),fStiffnessScale(0), bCopyJointVelocities(false),
pParticle(NULL),pBuoyancy(NULL),pPlayerDimensions(NULL),pPlayerDynamics(NULL),
pCar(NULL),pAreaDef(NULL),nLod(0),szPropsOverride(0) {};
[Code] ....
I have a big problem with searching a solution for getting access on getters and setters of the derived classes of an interface.
Interface:
class IfParam
{
public:
IfParam();
};
Now I have a derived class for each needed datatype. E.g.
class Int32Param: public IfParam
{
public:
Int32Param();
Int32Param(IfParam* l_param);
int getValue();
void setValue(int l_value);
private:
[Code]...
My Problem now ist getting access to the getters/setters over the interface. I wish I could initialize the Params like this:
IfParam* param = new Int32Param();
param.setValue(12);
IfParam* param = new StringParam();
param.setValue("String");
But to have access to the getter/setter I have to declaire the functions in the interface as generic functions. But how? I tried to use temlates, but then i have to declaire IfParam as IfParam<int>. Thats a problem because in my original program I do not know which TypeParam the IfParam interface will be initialized with when I create the pointer.
I don't understand why my compiler gives me this error when I'm trying to run this code:
Code:
#include <iostream>
#include <cmath>
using namespace std;
class Airplane
{
public:
Airplane();
~Airplane();
[Code]...
The variable is protected. Yeah, that's right. But shouldn't a derived class be able to reach it? Or is it only in a function that the derived class is able to reach protected variables and isn't able to reach protected variables in the constructor?
Is is possible to force derived classed to overload certain operators, like we do with pure virtual functions?
Is this possible to dynamically bind objects to their respective overloaded operators?
I am getting errors with undefined references to my base class vtable when I hackly try to overload: Code: operator+ I am not sure whether this is possible.
I have one base class and one derived class.
class Base
{
protected:
int a, b;
[Code]....
The two definition of the derived class constructor
(Derived(int aa, int bb, int cc) { Base(aa, bb); c = cc; }
and
Derived(int aa, int bb, int cc) : Base(aa, bb), c(cc) {}
looks identical but first one does not work.
So, I wounder what the difference between them?
I have a class Base (abstract, with pure virtual) and Derived (which inherit Base). I use this:
Base* A = new Derived();
But I can do this:
Derived A;
How make Derived dependent of Base in one file?