问题
Am I misunderstanding something about bindings? I bind (an NSArrayController's content) to an NSDictionary's "allValues" array, and it thinks it's empty. I bind to a random object with a property that I've set to be that same NSDictionary's "allValues" array, and it works fine.
Is this expected behavior, or am I doing something wrong? Furthermore, if this is expected, what is the standard way to deal with this? Making relatively purposeless objects just to hold arrays in properties so I can bind to them seems ugly.
回答1:
Binding to @"allValues" means the dictionary is sent a -valueForKey:@"allValues" message. The dictionary then interprets that by looking up -objectForKey:@"allValues" which is not what you are after in this case.
Try binding to @"@allValues" instead (see the -[NSDictionary valueForKey:] docs for more details)
来源：https://stackoverflow.com/questions/2285844/binding-to-an-nsdictionarys-allvalues-array