WinRT too many errors in base.h - visual-studio

I am using Visual Studio and trying to compile simple WinRT example:
pch.h:
// pch.h
#pragma once
#include <Windows.h>
#include <winrt/Windows.Foundation.Collections.h>
#include <winrt/Windows.Web.Syndication.h>
#include <iostream>
ConsoleApplication2.h:
#include "pch.h"
using namespace winrt;
using namespace Windows::Foundation;
using namespace Windows::Web::Syndication;
int main()
{
winrt::init_apartment();
Uri rssFeedUri{ L"https://blogs.windows.com/feed" };
SyndicationClient syndicationClient;
SyndicationFeed syndicationFeed = syndicationClient.RetrieveFeedAsync(rssFeedUri).get();
for (const SyndicationItem syndicationItem : syndicationFeed.Items())
{
winrt::hstring titleAsHstring = syndicationItem.Title().Text();
std::wcout << titleAsHstring.c_str() << std::endl;
}
}
I get "too many errors" in winrt\base.h library file.
What I do wrong and how to compile this simple example?

I guess i found solution.
Visual Studio Menu -> Project -> Manage NuGet Packages -> Browse
install Microsoft.Windows.CppWinRT
Rebuild.

Related

"GetForegroundWindow: identifier not found" in visual studio 2015

I am developing a windows app in visual studio 2015 using C++. I need GetForegroundWindow() and GetWindowText() to return the app that is currently focusing on. However, it says GetForegroundWindow() and GetWindowText() are undefined even I've included "windows.h". I tried go to the definition of GetForegroundWindow(), it led me to "WinUser.h", so I included "WinUser.h" as well. But it still could not help. Here are my code:
#include "MainPage.xaml.h"
#include <windows.h>
#include <WinUser.h>
#include <winapifamily.h>
#include <string>
#include <stdio.h>
#include <iostream>
using namespace App1;
using namespace Platform;
using namespace Windows::Foundation;
using namespace Windows::Foundation::Collections;
using namespace Windows::UI::Xaml;
using namespace Windows::UI::Xaml::Controls;
using namespace Windows::UI::Xaml::Controls::Primitives;
using namespace Windows::UI::Xaml::Data;
using namespace Windows::UI::Xaml::Input;
using namespace Windows::UI::Xaml::Media;
using namespace Windows::UI::Xaml::Navigation;
using std::cout;
using std::endl;
MainPage::MainPage()
{
InitializeComponent();
}
HWND currenthwnd, hwnd = NULL;
char wnd_title[1024];
void App1::MainPage::Focus_app_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
currenthwnd = GetForegroundWindow();
GetWindowText(hwnd, wnd_title, sizeof(wnd_title));
cout << wnd_title << endl;
}
Any ideas? Thanks in advance!
GetForegroundWindowand GetWindowText in the WinUser.h are declared inside #if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) macro block. So you could use them only for windows desktop applications.

How to wrap a c++ class with an opencv object with c++/cli

I would like to wrap a complex c++ class which used opencv object with c++/cli for using in c# and vb. I'm using Visual Studio 2015. I'm using the x64 versions of of the OpenCV library and compiling also to x64.
Following is the header.h file of a small test class, just as an example:
#pragma once
#include <vector>
#include "opencv2/opencv.hpp"
using namespace std;
class compC
{
public:
compC(int * pInt, int arrSize);
int sumArray();
private:
vector<int> vec;
cv::Mat img;
};
This is going to be compiled as a win32-application to a .lib file without any problems.
The example wrapper class (wrapper.h) would look like:
#pragma once
#include "../ConsoleApplication1/header.h"
#include "../ConsoleApplication1/body.cpp"
using namespace System;
namespace WrapperLibrary {
public ref class WrapperClass
{
public:
WrapperClass(int * pInt, int arraySize);
int getSum();
private:
compC * pcC;
int sum;
};
}
The second class would be compiled as a dll with /clr (as c++/cli project).
First I got an error that opencv.hpp could not be find and had to add the include directory of opencv in to the wrapper project. But I cannot compile it and get a lot of errors, mainly pointing to linking problems "unresolved external problems ..." in connection with the opencv-mat object.
If I remove the lines
#include "opencv2/opencv.hpp"
and
cv::Mat img;
in the test class (header.h) all will be fine.
What did I made wrong? How can I wrap those c++ class with c++/cli?

Error while trying to use strings while working with windows application forms

When creating a new class while working in a project that is based around windows application forms. I have a problem where string becomes unusable. I get errors the say things like
"a member of a managed class cannot be of a non-managed class type"
"IntelliSense: a function type involving a generic parameter cannot have an ellipsis parameter"
"IntelliSense: linkage specification is incompatible with previous "bsearch_s"(declared at line 426)"
Person.h
#pragma once
#include <string>
using namespace std;
ref class Person
{
public:
Person(void);
string name;
};
Person.cpp
#include "stdafx.h"
#include "Person.h"
#include <string>
using namespace std;
Person::Person(void)
{
name = "Bob";
}
If someone has a solution to this or a work around that isn't creating my own string class I would love to hear it as this has been bothering me for days.
String header in CLI C++ is already included in the System namespace.
String works as a pointer. Using the cap ^ handler
//This works:
#include "stdafx.h"
using namespace System;
void function()
{
String^ simpleStr = "Bob";
}

Error "C3145" and "C2061" in C++ Visual Studio

EDIT: What is C++/CLI? I am programming in Visual studio, and as far as I know using C++... Also, The first error was solved by Peter's comment, but I am still stuck on the second.
I am brand new to the world of C++, and have previously done all my work in Java. I am unfamiliar with the use of pointers and garbage collection (though I believe I understand the concept) and I believe that may be the source of my problems. I am getting the following error messages:
1>Runner.cpp(6): error C3145: 'formOutOfTime' : global or static variable may not have managed type 'System::Windows::Forms::Form ^'
1> may not declare a global or static variable, or a member of a native type that refers to objects in the gc heap
1>Runner.cpp(22): error C2061: syntax error : identifier 'FormOutOfTime'
My code is like this:
PurpleHealth.cpp (This is the file I believe the system calls to start it all off):
#include "FormOutOfTime.h"
#include "FormParentalOverride.h"
#include "Runner.h"
using namespace PurpleHealth;
[STAThreadAttribute]
int main(array<System::String ^> ^args)
{
// Enabling Windows XP visual effects before any controls are created
Application::EnableVisualStyles();
Application::SetCompatibleTextRenderingDefault(false);
// Create the main window and run it
//Application::Run(gcnew FormOutOfTime());
Runner* runner = new Runner();
//delete runner;
return 0;
}
Runner.h (this is the header file I want to run all my main code, and launch the forms. I also struggle with the purpose behind the header files)
#include "stdafx.h"
#include "FormOutOfTime.h"
#include "FormParentalOverride.h"
class Runner
{
public:
Runner();
~Runner();
// functions
private:
void Go();
// member variables
};
And Finally Runner.cpp:
#include "stdafx.h"
#include "Runner.h"
#include "FormOutOfTime.h"
#include "FormParentalOverride.h"
//Variable Dclaration
System::Windows::Forms::Form^ formOutOfTime;//Error Here***************************
Runner::Runner()
{
// Do stuff if you need to
this->Go();
}
Runner::~Runner()
{
// Clear memory if you need to
}
void Runner::Go()
{
formOutOfTime = gcnew FormOutOfTime();//Error Here***************************
formOutOfTime->ShowDialog();
}
Please help me solve these messages, and even critique on form is appreciated. Thanks.
managed pointers cannot be declared at static or global scope. They can only be declared at function scope. Move the declaration of formOutOfTime from the top of the runner.cpp file to within the Go method

linking error when trying to use boost::asio

I think i'm getting crazy, im trying to compile a simple project to understand how to work with io_service and I cant compile it.
#include <iostream>
#include <boost/asio.hpp>
#include <boost/bind.hpp>
class testClass
{
unsigned int other_number;
unsigned int main_number;
boost::asio::io_service& io_serv;
public:
testClass(boost::asio::io_service& io) : other_number(0), io_serv(io), main_number(0){io_serv.post(boost::bind(&testClass::printNumbers, this));}
void changeNumber(int num)
{
io_serv.post(boost::bind(&testClass::doChangeNumber, this, num));
}
private:
void doChangeNumber(int num)
{
main_number = num;
}
void printNumbers()
{
std::cout<<"Main number is: "<<main_number<<" Other number is:"<<other_number<<std::endl;
other_number++;
Sleep(1000);
io_serv.post(boost::bind(&testClass::printNumbers, this));
}
};
void main()
{
boost::asio::io_service io_serv;
testClass tc(io_serv);
io_serv.run();
int num = 0;
while (true)
{
tc.changeNumber(num++);
Sleep(2000);
}
}
I did add in "project property->c/c++->general->additional include directories" the line: "C:\Program Files (x86)\boost_1_44_0";
And I did add in "project property->linker->additional library directories" the line: "C:\Program Files (x86)\boost_1_44_0\libs";
but nothing seems to work...
I'm using visual studio 2010..
there are no .lib files in boost_1_44_0\libs... I downloaded it 2 times from boost's site just to make sure..
no matter what I do, I always get LINK : fatal error LNK1104: cannot open file 'libboost_system-vc100-mt-gd-1_44.lib'
You can build the Boost libs on your local system using bjam as described here (Section 5.2). Once you have done that you should be good to go - use this from a Visual Studio command prompt and make sure your project has the correct LIB path.
The prebuilt libs will only be there by default if you use the installer from Boost Pro Computing, I believe.

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