Hi all.
I'm trying to follow the HIDManager documentation to setup some Joystick/Gampage code to my app.
In my obj-c class I have started two methods (see below).
The first is incomplete as I have hit a warning that I don't understand and wish to get rid of this :
Passing 'CFArrayRef' (aka 'const struct__CFArray *') to parameter of type 'CFMutableArrayRef' ( 'const struct__CFArray *') discards qualifiers.
What's that exactly mean and how would I rectify my code to remove the warning?
Cheers
Steve
- (void) openHardwareConnection
{
HIDManager = IOHIDManagerCreate(kCFAllocatorDefault, kIOHIDOptionsTypeNone);
CFArrayRef matchingCFArrayRef = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
CFDictionaryRef matchingCFDictRef = [self buildDeviceMatchingCFDictionaryRef : kHIDPage_GenericDesktop : kHIDUsage_GD_Joystick];
CFArrayAppendValue(matchingCFArrayRef, matchingCFDictRef); // WARNING HERE
matchingCFDictRef = [self buildDeviceMatchingCFDictionaryRef : kHIDPage_GenericDesktop : kHIDUsage_GD_GamePad];
CFArrayAppendValue(matchingCFArrayRef, matchingCFDictRef); // WARNING HERE
CFRelease(matchingCFDictRef);
//...... more hid stuff to follow
}
- (CFMutableDictionaryRef) buildDeviceMatchingCFDictionaryRef : (UInt32) inUsagePage : (UInt32) inUsage
{
// Create a dictionary to add usage page/usages to
CFMutableDictionaryRef HIDDeviceMatchingCFDictionaryRef = CFDictionaryCreateMutable( kCFAllocatorDefault, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks );
CFNumberRef pageCFNumberRef = CFNumberCreate( kCFAllocatorDefault, kCFNumberIntType, &inUsagePage );
CFDictionarySetValue( HIDDeviceMatchingCFDictionaryRef, CFSTR(kIOHIDDeviceUsagePageKey), pageCFNumberRef );
CFRelease(pageCFNumberRef);
CFNumberRef usageCFNumberRef = CFNumberCreate( kCFAllocatorDefault, kCFNumberIntType, &inUsage );
CFDictionarySetValue(HIDDeviceMatchingCFDictionaryRef, CFSTR(kIOHIDDeviceUsageKey), usageCFNumberRef);
CFRelease(usageCFNumberRef);
return HIDDeviceMatchingCFDictionaryRef;
}
