Easy-to-develop tutorial for IOS---Touch ID password

Support Systems and Models:The minimum supported system for the iOS system's fingerprint identification is, iPhone 5s although the 5s model of the iOS 8 installation iOS 7 system can use the system-provided fingerprint unlocking function, but because it is API not open, theoretically third-party software is not available. Dependent framework:

Localauthentication.framework#import <LocalAuthentication/LocalAuthentication.h>

Precautions: iOS 8 When you do the following versions, be sure to validate the API to avoid invoking the associated API to cause a crash. Use class: LAContext Fingerprint Validation Action objectCode:

-(void) authenticateuser{//Initialize context object lacontext* contextual = [[Lacontext alloc] init];    Wrong object nserror* error = Nil;    nsstring* result = @ "Authentication is needed to access your notes."; First use Canevaluatepolicy to determine if the device supports the status if ([Context Canevaluatepolicy:lapolicydeviceownerauthenticationwithbiometrics Error:&error]) {//Support fingerprint verification [context Evaluatepolicy:lapolicydeviceownerauthenticationwithbiometrics Locali            Zedreason:result reply:^ (BOOL success, Nserror *error) {if (success) {//validation succeeded, main thread processing UI                } else {NSLog (@ "%@", error.localizeddescription); Switch (error.code) {case laerrorsystemcancel: {NSLog (@ "Aut                        Hentication is cancelled by the system ");                    Switch to another app, the system cancels the verification touch ID break;        } Case Laerrorusercancel: {                NSLog (@ "Authentication is cancelled by the user");                    User cancels authentication touch ID break; } case Laerroruserfallback: {NSLog @ ' User selected to enter                        Custom password ");                        [[Nsoperationqueue Mainqueue] addoperationwithblock:^{//user Select Enter password, switch main thread processing                        }];                    Break } default: {[[Nsoperationqueue Mainqueue] Addoperationwithbl                        ock:^{//Other case, switch main thread processing}];                    Break    }                }            }        }];            } else {//does not support fingerprint identification, log out error details switch (error.code) {case laerrortouchidnotenrolled:                {NSLog (@ "TouchID is not enrolled");            Break} case Laerrorpasscodenotset: {NSLog (@ "A passcode have not been set");            Break                } default: {NSLog (@ "TouchID not available");            Break        }} NSLog (@ "%@", error.localizeddescription);    [Self showpasswordalert]; }}

typedef ns_enum (Nsinteger, laerror) {    //authorization failed    laerrorauthenticationfailed = klaerrorauthenticationfailed,    //user cancels Touch ID authorization    Laerrorusercancel           = klaerrorusercancel,    //user chooses to enter password    laerroruserfallback         = Klaerroruserfallback,    //System de-authorization (such as other app cut-in)    Laerrorsystemcancel         = klaerrorsystemcancel,    //System not set password    laerrorpasscodenotset       = Klaerrorpasscodenotset,    //device Touch ID not available, for example not open    laerrortouchidnotavailable  = Klaerrortouchidnotavailable,    //device Touch ID not available, user not input    laerrortouchidnotenrolled   = Klaerrortouchidnotenrolled,} ns_enum_available (10_10, 8_0);

Operation Flow:First judge the system version, iOS 8 and the above version of the implementation -(void)authenticateUser method, the method automatically determine whether the device support and open Touch ID .

Easy development tutorial for IOS---Touch ID password