在代码中使用了相对布局框架Masonry
准备两张图片，一张是扫描边框，一张是扫描时的细线分别命名
scanFrame.png和scanLine.png并提前放入工程
导入相对布局头文件
#define MAS_SHORTHAND
#define MAS_SHORTHAND_GLOBALS
#import "Masonry.h"
导入依赖头文件
#import <AVFoundation/AVFoundation.h>
具体代码如下：
static const char *KEYScanQRCodeQueueName = "ScanQRCodeQueue";
@interface ViewController ()<AVCaptureMetadataOutputObjectsDelegate>
@property (nonatomic,strong)UIImageView *line;;
@property (nonatomic,strong) AVCaptureSession *scanSession;
@property (nonatomic,strong) AVCaptureVideoPreviewLayer *scanLayer;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler: ^(BOOL granted) {
if (granted) {
[self startReading];
} else {
NSLog(@"请授权访问相机"); }
}];
}
//开始扫描
- (BOOL)startReading
{
// 获取 AVCaptureDevice 实例
NSError * error;
AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
// 初始化输入流
AVCaptureDeviceInput *inputStream = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&error];
if (!inputStream) {
NSLog(@"%@", [error localizedDescription]);
return NO;
}
// 创建会话
_scanSession = [[AVCaptureSession alloc] init];
// 添加输入流
[_scanSession addInput:inputStream];
// 初始化输出流
AVCaptureMetadataOutput *captureMetadataOutput = [[AVCaptureMetadataOutput alloc] init];
// 添加输出流
[_scanSession addOutput:captureMetadataOutput];
// 创建dispatch queue.
dispatch_queue_t dispatchQueue;
dispatchQueue = dispatch_queue_create(KEYScanQRCodeQueueName, NULL);
[captureMetadataOutput setMetadataObjectsDelegate:self queue:dispatchQueue];
// 设置元数据类型 AVMetadataObjectTypeQRCode
[captureMetadataOutput setMetadataObjectTypes:[NSArray arrayWithObject:AVMetadataObjectTypeQRCode]];
// 创建输出对象
_scanLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:_scanSession];
[_scanLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
[_scanLayer setFrame:self.view.bounds];
[self.view.layer addSublayer:_scanLayer];
[self setOverlayPickerView];
// 开始会话
[_scanSession startRunning];
return YES;
}
//结束扫描
- (void)stopReading
{
[_scanSession stopRunning];
_scanSession = nil;
}
//扫描结果
-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects
fromConnection:(AVCaptureConnection *)connection
{
if (metadataObjects != nil && [metadataObjects count] > 0) {
AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0];
NSString *result;
if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) {
result = metadataObj.stringValue;
} else {
NSLog(@"不是二维码");
}
[self performSelectorOnMainThread:@selector(reportScanResult:) withObject:result waitUntilDone:NO];
}
}
//处理结果
- (void)reportScanResult:(NSString *)result
{
[self stopReading];
NSLog(@"%@",result);
}
//添加识别途中动画
- (void)setOverlayPickerView
{
//左侧的view
UIView *leftView = [UIView new];
leftView.alpha = 0.5;
leftView.backgroundColor = [UIColor blackColor];
[self.view addSubview:leftView];
[leftView makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(self.view.top);
make.bottom.equalTo(self.view.bottom);
make.left.equalTo(self.view.left);
make.width.equalTo(30);
}];
//右侧的view
UIView *rightView = [UIView new];
rightView.alpha = 0.5;
rightView.backgroundColor = [UIColor blackColor];
[self.view addSubview:rightView];
[rightView makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(self.view.top);
make.bottom.equalTo(self.view.bottom);
make.right.equalTo(self.view.right);
make.width.equalTo(30);
}];
//最上部view
UIView* upView = [UIView new];
upView.alpha = 0.5;
upView.backgroundColor = [UIColor blackColor];
[self.view addSubview:upView];
[upView makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(self.view.top);
make.left.equalTo(leftView.right);
make.right.equalTo(rightView.left);
make.height.equalTo(30);
}];
//扫描框
UIImageView *centerView = [UIImageView new];
centerView.center = self.view.center;
centerView.image = [UIImage imageNamed:@"scanFrame.png"];
centerView.contentMode = UIViewContentModeScaleAspectFit;
centerView.backgroundColor = [UIColor clearColor];
[self.view addSubview:centerView];
[centerView makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(upView.bottom);
make.left.equalTo(leftView.right);
make.right.equalTo(rightView.left);
make.height.equalTo(upView.width);
}];
//底部view
UIView * downView = [UIView new];
downView.alpha = 0.5;
downView.backgroundColor = [UIColor blackColor];
[self.view addSubview:downView];
[downView makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(centerView.bottom);
make.left.equalTo(leftView.right);
make.right.equalTo(rightView.left);
make.bottom.equalTo(self.view.bottom);
}];
_line = [UIImageView new];
_line.image = [UIImage imageNamed:@"scanLine.png"];
_line.contentMode = UIViewContentModeScaleAspectFill;
_line.backgroundColor = [UIColor clearColor];
[self addAnimation];
[self.view addSubview:_line];
[_line makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(centerView.top);
make.left.equalTo(centerView.left);
make.right.equalTo(centerView.right);
make.height.equalTo(2);
}];
//提示信息
UILabel *msg = [UILabel new];
msg.backgroundColor = [UIColor clearColor];
msg.textColor = [UIColor whiteColor];
msg.textAlignment = NSTextAlignmentCenter;
msg.font = [UIFont systemFontOfSize:16];
msg.text = @"将二维码放入框内,可识别车票";
[self.view addSubview:msg];
[msg makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(centerView.bottom).offset(20);
make.left.equalTo(self.view.left);
make.right.equalTo(self.view.right);
make.height.equalTo(30);
}];
}
- (void)addAnimation{
CABasicAnimation *animation = [self moveYTime:2 fromY:[NSNumber numberWithFloat:0] toY:[NSNumber numberWithFloat:screenWidth-60-2] rep:OPEN_MAX];
[line.layer addAnimation:animation forKey:@"animation"];
}
-(CABasicAnimation *)moveYTime:(float)time fromY:(NSNumber *)fromY toY:(NSNumber *)toY rep:(int)rep
{
CABasicAnimation *animationMove = [CABasicAnimation animationWithKeyPath:@"transform.translation.y"];
[animationMove setFromValue:fromY];
[animationMove setToValue:toY];
animationMove.duration = time;
animationMove.delegate = self;
animationMove.repeatCount = rep;
animationMove.fillMode = kCAFillModeForwards;
animationMove.removedOnCompletion = NO;
animationMove.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
return animationMove;
}
@end
说明scanFrame.PNG是扫描时候的边框需要自己提前放到自己工程里面。scanLine.png是扫描时候从上到下的细线提前放入工程