做iOS的二維碼掃描，有兩個(gè)第三方庫(kù)可以選擇，ZBar和ZXing。今天要介紹的是iOS7.0后AVFoundation框架提供的原生二維碼掃描。
首先需要添加AVFoundation.framework框架到你工程中build phase的"Link Binary With Libraries"之下，然后就可以開(kāi)始了。
一、做好準(zhǔn)備工作，搭建UI
UI效果如圖
IBOutlet、IBAction如下：
@property(weak, nonatomic) IBOutlet UIView *viewPreview;
@property(weak, nonatomic) IBOutlet UILabel *lblStatus;
@property(weak, nonatomic) IBOutlet UIButton *startBtn;
- (IBAction)startStopReading:(id)sender;
接下來(lái)就都是代碼的事情了
二、控制器ViewController.h
首先導(dǎo)入AVFoundation框架
1#import<AVFoundation/AVFoundation.h>
然后控制器實(shí)現(xiàn) AVCaptureMetadataOutputObjectsDelegate協(xié)議
1@interfaceViewController ()<AVCaptureMetadataOutputObjectsDelegate>
整體property如下：
@property(strong, nonatomic) UIView *boxView;
@property(nonatomic) BOOL isReading;
@property(strong, nonatomic) CALayer *scanLayer;
-(BOOL)startReading;
-(void)stopReading;
//捕捉會(huì)話
1@property (nonatomic, strong) AVCaptureSession *captureSession;
//展示layer
1@property(nonatomic, strong) AVCaptureVideoPreviewLayer *videoPreviewLayer;
然后在ViewDidLoad方法中初始化
- (void)viewDidLoad {
??[superviewDidLoad];
??_captureSession = nil;
???_isReading = NO;
}
接下來(lái)實(shí)現(xiàn)startReading方法（這可就是重點(diǎn)咯）
- (BOOL)startReading {
?NSError *error;
?//1.初始化捕捉設(shè)備（AVCaptureDevice），類(lèi)型為AVMediaTypeVideo
?AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
?//2.用captureDevice創(chuàng)建輸入流
?AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];
?if(!input) {
??NSLog(@"%@", [error localizedDescription]);
??returnNO;
?}
?//3.創(chuàng)建媒體數(shù)據(jù)輸出流
?AVCaptureMetadataOutput *captureMetadataOutput = [[AVCaptureMetadataOutput alloc] init];
?//4.實(shí)例化捕捉會(huì)話
?_captureSession = [[AVCaptureSession alloc] init];
?//4.1.將輸入流添加到會(huì)話
?[_captureSession addInput:input];
?//4.2.將媒體輸出流添加到會(huì)話中
?[_captureSession addOutput:captureMetadataOutput];
?//5.創(chuàng)建串行隊(duì)列，并加媒體輸出流添加到隊(duì)列當(dāng)中
?dispatch_queue_t dispatchQueue;
?dispatchQueue = dispatch_queue_create("myQueue", NULL);
?//5.1.設(shè)置代理
?[captureMetadataOutput setMetadataObjectsDelegate:self queue:dispatchQueue];
?//5.2.設(shè)置輸出媒體數(shù)據(jù)類(lèi)型為QRCode
?[captureMetadataOutput setMetadataObjectTypes:[NSArray arrayWithObject:AVMetadataObjectTypeQRCode]];
?//6.實(shí)例化預(yù)覽圖層
?_videoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:_captureSession];
?//7.設(shè)置預(yù)覽圖層填充方式
?[_videoPreviewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
?//8.設(shè)置圖層的frame
?[_videoPreviewLayer setFrame:_viewPreview.layer.bounds];
?//9.將圖層添加到預(yù)覽view的圖層上
?[_viewPreview.layer addSublayer:_videoPreviewLayer];
?//10.設(shè)置掃描范圍
?captureMetadataOutput.rectOfInterest = CGRectMake(0.2f, 0.2f, 0.8f, 0.8f);
?//10.1.掃描框
?_boxView = [[UIView alloc] initWithFrame:CGRectMake(_viewPreview.bounds.size.width * 0.2f, _viewPreview.bounds.size.height * 0.2f, _viewPreview.bounds.size.width - _viewPreview.bounds.size.width * 0.4f, _viewPreview.bounds.size.height - _viewPreview.bounds.size.height * 0.4f)];
?_boxView.layer.borderColor = [UIColor greenColor].CGColor;
?_boxView.layer.borderWidth = 1.0f;
?[_viewPreview addSubview:_boxView];
?//10.2.掃描線
?_scanLayer = [[CALayer alloc] init];
?_scanLayer.frame = CGRectMake(0, 0, _boxView.bounds.size.width, 1);
?_scanLayer.backgroundColor = [UIColor brownColor].CGColor;
?[_boxView.layer addSublayer:_scanLayer];
?NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:0.2f target:self selector:@selector(moveScanLayer:) userInfo:nil repeats:YES];
?[timer fire];
?//10.開(kāi)始掃描
?[_captureSession startRunning];
?returnYES;
}
實(shí)現(xiàn)AVCaptureMetadataOutputObjectsDelegate協(xié)議方法
#pragma mark - AVCaptureMetadataOutputObjectsDelegate
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection
{
?//判斷是否有數(shù)據(jù)
?if(metadataObjects != nil && [metadataObjects count] > 0) {
??AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0];
??//判斷回傳的數(shù)據(jù)類(lèi)型
??if([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) {
???[_lblStatus performSelectorOnMainThread:@selector(setText:) withObject:[metadataObj stringValue] waitUntilDone:NO];
???[self performSelectorOnMainThread:@selector(stopReading) withObject:nil waitUntilDone:NO];
???_isReading = NO;
??}
?}
}
實(shí)現(xiàn)計(jì)時(shí)器方法moveScanLayer:(NSTimer *)timer
- (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:0.1animations:^{
???_scanLayer.frame = frame;
??}];
?}
}
實(shí)現(xiàn)開(kāi)始和停止方法
- (IBAction)startStopReading:(id)sender {
??if(!_isReading) {
???if([self startReading]) {
????[_startBtn setTitle:@"Stop"forState:UIControlStateNormal];
????[_lblStatus setText:@"Scanning for QR Code"];
???}
??}
??else{
???[self stopReading];
???[_startBtn setTitle:@"Start!"forState:UIControlStateNormal];
??}
??_isReading = !_isReading;
}
-(void)stopReading{
?[_captureSession stopRunning];
?_captureSession = nil;
?[_scanLayer removeFromSuperlayer];
?[_videoPreviewLayer removeFromSuperlayer];
}
以上內(nèi)容就是本文給大家介紹ios原生二維碼掃描的全部?jī)?nèi)容，希望大家喜歡。
