问题
I'm new to iOS, and am learning to code with Swift. My app needs to measure the signal strength. I've found this code working on Objective-C/C, and need some help to implement on Swift. Here is what I got. Hope someone can help me finish it.
OBJECTIVE C
int getSignalStrength()
{
void *libHandle = dlopen("/System/Library/Frameworks/CoreTelephony.framework/CoreTelephony", RTLD_LAZY);
int (*CTGetSignalStrength)();
CTGetSignalStrength = dlsym(libHandle, "CTGetSignalStrength");
if( CTGetSignalStrength == NULL) NSLog(@"Could not find CTGetSignalStrength");
int result = CTGetSignalStrength();
dlclose(libHandle);
return result;
}
SWIFT
func getSignalStrength()->Int{
var result : Int! = 0
let libHandle = dlopen ("/System/Library/Frameworks/CoreTelephony.framework/CoreTelephony", RTD_LAZY)
** help **
var CTGetSignalStrength = dlsym(libHandle, "CTGetSignalStrength")
if (CTGetSignalStrength != nil){
result = CTGetSignalStrength()
}
dlclose(libHandle)
return result
}
回答1:
Don't use dlopen to load CoreTelephony. Use import CoreTelephony
at the top of your Swift file. Then just use CTGetSignalStrength as if it were any other function.
回答2:
Swift 3 Solution
import CoreTelephony
import Darwin
static func getSignalStrength()->Int{
var result : Int = 0
//int CTGetSignalStrength();
let libHandle = dlopen ("/System/Library/Frameworks/CoreTelephony.framework/CoreTelephony", RTLD_NOW)
let CTGetSignalStrength2 = dlsym(libHandle, "CTGetSignalStrength")
typealias CFunction = @convention(c) () -> Int
if (CTGetSignalStrength2 != nil) {
let fun = unsafeBitCast(CTGetSignalStrength2!, to: CFunction.self)
let result = fun()
return result;
print("!!!!result \(result)")
}
return -1
}
来源:https://stackoverflow.com/questions/25429732/ios-get-signal-strength-in-swift-core-telephony