I'm trying to access the val开发者_如何学Goues from a CFDictionary. I've started by implementing code suggested in this question:
CFTypeRef r = IOPSCopyPowerSourcesInfo();
CFArrayRef array = IOPSCopyPowerSourcesList(r);
CFDictionaryRef powerDic = IOPSGetPowerSourceDescription(array, r);
I have looked at the documentation plus other posts, but it's a bit beyond me how to work it.
What I really need is some example code that takes the code I already have and uses it to print a string of, for example, "Current Capacity".
CFDictionaryRef
is "toll free bridged" with NSDictionary
. This means you can cast one to the other interchangeably. In other words:
...
NSDictionary * powerDic = (NSDictionary *)IOPSGetPowerSourceDescription(array, r);
NSString * aValue = [powerDic objectForKey:@"aKey"];
If (for some reason) you need to stay at the CoreFoundation level (which isn't unheard-of), you'd use something like CFDictionaryGetValue()
.
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