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How to check if a file exists in Documents folder?
... Or just [0] via index accessing
– temporary_user_name
Dec 16 '14 at 0:09
firstObject is more safe than [0] a...
Delete local Git branches after deleting them on the remote repo
...t long, you might want to add an alias to your .zshrc or .bashrc. Mine is called gbpurge (for git branches purge):
alias gbpurge='git branch --merged | grep -Ev "(\*|master|develop|staging)" | xargs -n 1 git branch -d'
Then reload your .bashrc or .zshrc:
. ~/.bashrc
or
. ~/.zshrc
...
How to override the copy/deepcopy operations for a Python object?
...ully, but this is the first time I've actually gone about overloading the __copy__ and __deepcopy__ methods. I've already Googled around and looked through the built-in Python modules to look for instances of the __copy__ and __deepcopy__ functions (e.g. sets.py , decimal.py , and fracti...
What is the performance cost of having a virtual method in a C++ class?
...3ghz in-order PowerPC processor. On that architecture, a virtual function call costs 7 nanoseconds longer than a direct (non-virtual) function call.
So, not really worth worrying about the cost unless the function is something like a trivial Get()/Set() accessor, in which anything other than inli...
How to limit UITableView row reordering to a section
... hitting my head over this one, and google was turning up nothing.
I eventually worked it out and thought I'd write it up here for the sake of the next person.
...
Opening Android Settings programmatically
How can I open settings programmatically?
11 Answers
11
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How to get the width and height of an android.widget.ImageView?
...eight, finalWidth;
final ImageView iv = (ImageView)findViewById(R.id.scaled_image);
final TextView tv = (TextView)findViewById(R.id.size_label);
ViewTreeObserver vto = iv.getViewTreeObserver();
vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
...
C++中智能指针的设计和使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
...释放对象拥有权限、引用计数等，控制权转移等）。auto_ptr 即是一种常见的智能指针。
智能指针通常用类模板实现：
template <class T>
class smartpointer
{
private:
T *_ptr;
public:
smartpointer(T *p) : _ptr(p) //构造函数
{
}
T& oper...
Completion handler for UINavigationController “pushViewController:animated”?
...rface UINavigationController (CompletionHandler)
- (void)completionhandler_pushViewController:(UIViewController *)viewController
animated:(BOOL)animated
completion:(void (^)(void))completion;
@end
Implementation:
#import "UIN...
How to check which version of v8 is installed with my NodeJS?
How is V8 installed along with NodeJs? What version is my current V8 engine?
12 Answers
...