大约有 2,196 项符合查询结果（耗时：0.0202秒） [XML]
Function pointers, Closures, and Lambda
...riables. The compiler created a new closure (not function) dynamically by allocating a new record containing a pointer to the same code, but with different values for the free variables.
You can simulate all this in C, but it is a pain in the ass. Two techniques are popular:
Pass a pointer to ...
How do I do base64 encoding on iOS?
...t placeholder and pointer within that placeholder
strResult = (char *)calloc((((intLength + 2) / 3) * 4) + 1, sizeof(char));
objPointer = strResult;
// Iterate through everything
while (intLength > 2) { // keep going until we have less than 24 bits
*objPointer++ = _base64...
Objective-C parse hex string to integer
... I'm going with this method, way simpler (and potentially quicker) than allocating an nsscanner.
– Chris
Jun 1 '11 at 6:25
1
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UILongPressGestureRecognizer gets called twice when pressing down
...
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc]
initWithTarget:self
action:@selector(handleLongPress:)];
longPress.minimumPressDuration = 1.0;
[myView addGestureRecognizer:lon...
What exception classes are in the standard C++ library
...;exception> interface (debatable if you should catch this)
std::bad_alloc <new> failure to allocate storage
std::bad_array_new_length <new> invalid array length
std::bad_cast <typeinfo> execution of an invalid dynamic-cast
std::bad_exception <exception>...
Always pass weak reference of self into block in ARC?
... be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, should I always use a weak reference of self in a block ?
...
Total number of items defined in an enum
...h the Enum.GetValues and Enum.GetNames as listed above seem like they risk allocating a whole new array just to get a fixed length, which seems... well, horrible. Does anyone know if this approach does indeed incur dynamic allocation? If so, for certain use cases it seems far and away the most perfo...
How to make completely transparent navigation bar in iOS 7
...or];
[self.navigationController.navigationBar setBackgroundImage:[[UIImage alloc] init] forBarMetrics:UIBarMetricsDefault];
self.navigationController.navigationBar.shadowImage = [[UIImage alloc] init];
self.navigationController.navigationBar.backgroundColor = [UIColor clearColor];
...
How to Get True Size of MySQL Database?
...ld the table from scratch. When databases store information on disks, they allocate it in blocks; deleting a record often frees a block between used blocks, and it's very expensive to shift all of the other blocks around to use that space up so it is marked as "free". The space may be used later by ...
iOS app error - Can't add self as subview
...^(MyUser *user) {
ProfileViewController *pvc = [[ProfileViewController alloc] initWithUser:user];
[_dataViewController.navigationController pushViewController:pvc animated:YES navigationLock:lock];
}];
Basically, the rule is: before any non user related delays grab a lock from the relevant...