Re: NSTableView data source issue - code moving from xcode 3 to xcode 4
On 9 Oct 2011, at 11:41 AM, Peter Hudson wrote:
> I have found a solution in overriding the dataSource method in my table view
> subclass and simply returning [self dataSource] cast to the class which I
> know the datasource to be.
Why override the method, when all you can just cast the return value?
@implementation MyTableViewClass
- (void) myMethod
{
DataSourceClass * aVar = (DataSourceClass *) [self dataSource];
// ...
}
// ...
@end
You will have to make sure that DataSourceClass declares it complies with
.
— F
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Re: NSTableView data source issue - code moving from xcode 3 to xcode 4
On Oct 9, 2011, at 9:41 AM, Peter Hudson wrote: > For a long time ( in xcode 3 ) when I want to access a table view data > source ( in the sub class code for the table view ) I simply called [self > dataSource] > I would then call methods declared and implemented on the class which I new > to be the datasource. This worked fine. > > In xcode 4 ( sdk 10.7 ) the compiler throws a semantic warning when I do > this. It complains that the return value from [self dataSource] is ignorant > of the methods I am calling on it. This probably happened because you changed the base SDK from 10.5 to 10.6+. In the 10.6 SDK Apple introduced @protocols for most delegates/data-sources/etc instead of making them “informal protocols” aka categories. So the -delegate/-dataSource properties now no longer return an untyped “id” but a typed protocol reference like “id”. The benefit is that the compiler can now type-check it. The drawback is that the compiler will now type-check it :) If you know your data source is of, say, class MyDataSource, then all you need to do is add a cast: [(MyDataSource*)[self dataSource] myCustomMethod] —Jens ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
NSTableView data source issue - code moving from xcode 3 to xcode 4
Hi There For a long time ( in xcode 3 ) when I want to access a table view data source ( in the sub class code for the table view ) I simply called [self dataSource] I would then call methods declared and implemented on the class which I new to be the datasource. This worked fine. In xcode 4 ( sdk 10.7 ) the compiler throws a semantic warning when I do this. It complains that the return value from [self dataSource] is ignorant of the methods I am calling on it. I have found a solution in overriding the dataSource method in my table view subclass and simply returning [self dataSource] cast to the class which I know the datasource to be. This feels evil. Is there a nicer way to do this ? Peter ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
