TiMoch

How to get confused by VC++

Today, I came across a confusing compilation error with MS VC++ using a std::unique_ptr with a custom deleter. Here the code snippet:

#include <memory>
#include <string>

typedef void (*void_delete)(void *);

template<typename T>
void void_deleter(void * ptr) { delete reinterpret_cast<T*>(ptr); }

std::unique_ptr<void, void_delete> f1() {
return std::unique_ptr<void, void_delete>(new std::string("haha"), void_deleter);
}
std::unique_ptr<void, void_delete> f2() {
return std::unique_ptr<void, void_delete>(nullptr);
}

#include <memory>

#include <string>

typedef void (*void_delete)(void *);

template<typename T>

void void_deleter(void * ptr) { delete reinterpret_cast<T*>(ptr); }

std::unique_ptr<void, void_delete> f1() {

return std::unique_ptr<void, void_delete>(new std::string("haha"), void_deleter);

}

std::unique_ptr<void, void_delete> f2() {

return std::unique_ptr<void, void_delete>(nullptr);

}

The compiler complains : 12345678910111213c:\program files (x86)\microsoft visual studio 10.0\vc\include\memory(2218): error C2338: unique_ptr constructed with null deleter pointer 1> c:\program files (x86)\microsoft visual studio 10.0\vc\include\memory(2214) : while compiling class template member function […]

Animate a UIView out of thin air

Today, I was trying to animate a menu-like view so that it slides out of a bar of buttons at the bottom of my application. Easy enough, I read some documentation about animations here. And I end up with code similar to this in the controller responsible for the sliding view:

CGRect frame = self.view.frame;
// make sure the view initially sits outside the screen
frame.origin.y = 480;
self.view.frame = frame;

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1];
frame.origin.y = referenceFrame.origin.y - frame.size.height;
self.view.frame = frame;
[UIView commitAnimations];

CGRect frame = self.view.frame;

// make sure the view initially sits outside the screen

frame.origin.y = 480;

self.view.frame = frame;

[UIView beginAnimations:nil context:NULL];

[UIView setAnimationDuration:1];

frame.origin.y = referenceFrame.origin.y - frame.size.height;

self.view.frame = frame;

[UIView commitAnimations];

Nothing spectacular. I […]

Transparent background UISearchView

While I was working on a small iPhone application I was required to put a search box but with a transparent background. The original design looks like this: I could not get the basic search control to not display its background. I tried using a standard text box, however the look and feel was not […]

Setting up an Android development environment

I am a newbie with mobile application development. As I start fiddling around, I find it is not exactly straightforward to setup an Android development environment for the first time. This post tries to take you through the few steps required before you can run a very first Android application. Installing Eclipse First you want […]

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