Writing a program that uses Kunth's dancing links algorithm. In C++ I'd use
n1->head->size--
this works,
[[n1 head]setSize:[[n1 head]size] - 1];
but it doesn't seem idiomatic. Is there a better way? Thanks.
I figured it out...
n1.head.size--;
Related
GPermission seems to have little to no documentation. How do you actually use it? (I'm currently using it for a GTK LockButton).
I agree, the documentation is pretty lacking. GPermission is an abstract base class which isn't particularly useful by itself. You need something which actually implements GPermission, like polkit.
There are some examples in gnome-control-center, like the datetime panel.
You need to subclass GPermission. When you need to change the values, you call g_permission_impl_update. Very non-intuitive, but yeah that's how it's done.
Google found me this straight away: https://developer.gnome.org/gio/2.26/GPermission.html
Is that not sufficient?
I googled trying to find the answer, but failed.
It's actually a quick question, and i just don't have enough memory-management and objective-understanding to solve it properly by myself.
If someone ever user WEPopover library(great tool, thanks to developers https://github.com/werner77/WEPopover), they remember that there is a warning in WEPopoverController.m:
//First force a load view for the contentViewController so the popoverContentSize is properly initialized
contentViewController.view;
and the warning as follows:
Property access result unused - getters should not be used for side effects
I'm not pretty sure what are they trying to achieve, but i truly believe it's not a propoer way to initialize things, but i am not sure if i should use any methods, because i don't want to disturb the functionality.
Any advices and hints will be hihgly appreciated!
I just solved it, I had the same issue! :)
just replace contentViewController.view; with [contentViewController view];
That's all. You might solved it, as you've asked it a longtime before! But it would be helpful to other if they will find the same issue:)
Is there a way to do a Spotlight query, in Obj-C, similar to what mdfind does? I need to write a method with the following signature:
-(NSString *)mdfind:(NSString *)theFileToLookFor
where the returned NSString is the first path found by the search.
Any help will be really appreciated.
NSMetadataQuery is the wrapper around the Carbon-level MDQuery API, which is how one interacts with the user's spotlight database.
the apis are in CoreServices.framework. start with the ones which have the prefix MDQuery
I know this is pretty much a stupid question. I know almost nothing about how compiler really works.
But recently I want find what symbol name does the compiler generate for my ivar, my methods.
Where and how can I know the answer? (I have only used some IDEs. So if the solution is better to be simple . And it would be great help if the instructions you provide is really explicit)
(By the way,is there any reference that i can learn about the things like this?)
PS.I'm IOS developer.And if gcc and LLVM works different answer on this question , I would like to know both.
You can use nm to dump the content of a binary object. Then, each compiler has its own way of mangling. I suggest you have a look at Name mangling for objective C in wikipedia, it will help you understand how mangling works.
Surely GCC and Clang must have compatible name-mangling schemes, since they can use each other's code.
If you are using XCode 3 select a source file and then pick "Show Assembly Code" from the Build menu.
Apparently XCode 4 users do not need assembly code :-(
Out of curiosity, what may the rationale behind these function names (found in Apple's Quartz Core framework) be?
ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv()
ZNK2CA6Render9Animation9next_timeEdRd()
ZN2CA11GenericRectIiE5insetEii()
Do you think the developers somehow encoded argument types in function names? How do you find yourself putting "EP19" in there in the course of day-to-day coding? In what circumstances do such barely readable function names actually help you read code and otherwise be more productive?
Thanks in advance for any hints, and Merry Christmas!
These 'mangled' names are automatically generated by the C++ compiler and indeed encode type information.