iOS 中二維碼掃描，ios掃描

iOS 中二維碼掃描，ios掃描

隨著的大量推廣，越來越多的人會在生活中用到二維碼這一個方便大家的功能。

因此，很多的app中也逐漸的都加入了二維碼這個元素，今天先給大家介紹一下iOS7後系統內建自己可以手動設計的二維碼掃描。

QRCodeViewController這個類是實現二維碼掃描建立的類，今天我寫的這個類似於官方文檔中的實現，可以直接掃描二維碼跳轉到當前二維碼對應的連結，如果是應用的話，會跳轉到appStore中對應的應用詳情。

 

除了這個，現在用的比較多的還有ZBarSDK等三方庫，實現的效果要比自己寫的這個漂亮，後面有機會的話，我會介紹一下ZBarSDK的用法以及經常遇到的問題和解決方案。

下面是主要實現：

 

#import "QRCodeViewController.h"

#import <AVFoundation/AVFoundation.h>

 

@interface QRCodeViewController () <AVCaptureMetadataOutputObjectsDelegate>

{

    BOOL _isReading;

}

 

@property (weak, nonatomic) IBOutlet UIView *ShowView;

 

 

@property (nonatomic,strong) UIView *boxView;

//@property (nonatomic,assign) BOOL *isReading;

@property (nonatomic,strong) CALayer *scanLayer;

 

 

@property (nonatomic,strong) UILabel *urlLabel;

 

-(BOOL)startReading;

-(void)stopReading;

 

//捕捉會話

@property (nonatomic,strong) AVCaptureSession *captureSession;

 

//展示layer

@property (nonatomic,strong) AVCaptureVideoPreviewLayer *videoPreviewLayer;

 

@end

 

@implementation QRCodeViewController

 

 

- (void)viewDidLoad {

    [super viewDidLoad];

    

    UIButton *btn = [UIButton buttonWithType:UIButtonTypeSystem];

    btn.frame = CGRectMake(0, 30, 50, 30);

    [btn setImage:[UIImage imageNamed:@"return@2x"] forState:UIControlStateNormal];

    [btn addTarget:self action:@selector(leftClicked) forControlEvents:UIControlEventTouchUpInside];

    [self.view addSubview:btn];

    

    _captureSession = nil;

    //_isReading = NO;

    [self startReading];

    

}

-(void)leftClicked{

    [self dismissViewControllerAnimated:YES completion:nil];

}

 

 

-(BOOL)startReading{

    NSError *error = nil;

    //1.初始化捕捉裝置(AVCaptureDevice),類型為AVMediaTypeVideo

    AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    //2.用captureDevice建立輸入資料流

    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];

    if (!input) {

        NSLog(@"%@",[error localizedDescription]);

        return NO;

    }

    //3.建立媒體資料輸出資料流

    AVCaptureMetadataOutput *captureMedataOutput = [[AVCaptureMetadataOutput alloc]init];

    //4.執行個體化捕捉會話

    _captureSession = [[AVCaptureSession alloc]init];

    //4.1將輸入資料流添加到會話

    [_captureSession addInput:input];

    //4.2將媒體輸出資料流添加到會話中

    [_captureSession addOutput:captureMedataOutput];

    //5.建立串列隊列，並將媒體輸出資料流添加到隊列中

    dispatch_queue_t dispatchQueue;

    dispatchQueue = dispatch_queue_create("myQueue", NULL);

    //5.1設定代理

    [captureMedataOutput setMetadataObjectsDelegate:self queue:dispatchQueue];

    

    //5.2設定輸出媒體資料類型為QRCode

    [captureMedataOutput setMetadataObjectTypes:[NSArray arrayWithObject:AVMetadataObjectTypeQRCode]];

    //6.執行個體化預覽圖層

    _videoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc]initWithSession:_captureSession];

    //7.設定預覽圖層填充方式

    [_videoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];

    //8.設定圖層的frame

    [_videoPreviewLayer setFrame:_ShowView.layer.bounds];

    //9.將圖層添加到預覽view的圖層上

    [_ShowView.layer addSublayer:_videoPreviewLayer];

    //10.設定掃描範圍

    captureMedataOutput.rectOfInterest = CGRectMake(0.2f, 0.2f, 0.8f, 0.8f);

    //10.1. 設定掃描框

    _boxView = [[UIView alloc]initWithFrame:CGRectMake(_ShowView.bounds.size.width * 0, _ShowView.bounds.size.height*0, _ShowView.bounds.size.width, _ShowView.bounds.size.height)];

    _boxView.layer.borderColor = [UIColor greenColor].CGColor;

    _boxView.layer.borderWidth = 1.0f;

    [_ShowView addSubview:_boxView];

    

    //10.2掃描線

    _scanLayer = [[CALayer alloc]init];

    _scanLayer.frame = CGRectMake(0, 0, _boxView.bounds.size.width, 2);

    _scanLayer.backgroundColor = [UIColor cyanColor].CGColor;

    [_boxView.layer addSublayer:_scanLayer];

    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:0.2f target:self selector:@selector(moveScanLayer:) userInfo:nil repeats:YES];

    [timer fire];

    

    //11.開始掃描

    [_captureSession startRunning];

    

    return 1;

}

 

-(void)moveScanLayer:(NSTimer *)timer{

    CGRect frame = _scanLayer.frame;

    if (_boxView.frame.size.height <= _scanLayer.frame.origin.y) {

        frame.origin.y = 0;

        _scanLayer.frame = frame;

    }

    else{

        frame.origin.y += 5;

        [UIView animateWithDuration:0.1 animations:^{

            _scanLayer.frame = frame;

        }];

    }

}

 

 

-(void)stopReading{

//    [_captureSession stopRunning];

//    _captureSession = nil;

//    [_scanLayer removeFromSuperlayer];

//    [_videoPreviewLayer removeFromSuperlayer];

}

 

 

#pragma mark - AVCaptureMetadataOutputObjectsDelegate

-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection{

    //判斷是否有資料

    if (metadataObjects !=nil && [metadataObjects count]>0) {

        AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0];

        //判斷回傳的資料類型

        if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) {

            [self performSelectorOnMainThread:@selector(setUrl:) withObject:[metadataObj stringValue] waitUntilDone:NO];

            

            //[[UIApplication sharedApplication] openURL:url];

            [self performSelectorOnMainThread:@selector(stopReading) withObject:nil waitUntilDone:NO];

            _isReading = NO;

        }

    }

}

 

-(void)setUrl:(NSString *)text{

    NSURL *url = [NSURL URLWithString:text];

    [[UIApplication sharedApplication] openURL:url];

}