系统二维码扫描 扫描框设置 rectOfInterest
#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>
@interface ViewController ()<WJScanningViewdelegate,AVCaptureMetadataOutputObjectsDelegate>
@property (nonatomic, strong) CIDetector *detecter;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
AVCaptureMetadataOutput *output = [[AVCaptureMetadataOutput alloc] init];
AVCaptureSession *session = [[AVCaptureSession alloc] init];
[session addInput:input];
[session addOutput:output];
[output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
[output setMetadataObjectTypes:@[AVMetadataObjectTypeQRCode]];
[output setRectOfInterest:CGRectMake(100/self.view.frame.size.height, 50/self.view.frame.size.width, 300/self.view.frame.size.height, 400/self.view.frame.size.width)];
AVCaptureVideoPreviewLayer *layer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
[layer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
[layer setFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[self.view.layer addSublayer:layer];
[session startRunning];
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(50, 100, 200, 200)];
view.backgroundColor = [UIColor clearColor];
view.layer.borderWidth = 1;
view.layer.borderColor = [UIColor redColor].CGColor;
[self.view addSubview:view];
//调整扫描区域 ，有些资料说设置 rectOfInterest
//CGRectMake(y/deviceHeight, x/deviceWidth, height/deviceHeight, width/deviceWidth);
解释下CGRectMake写法:都把x y width height 互换 了的.你扫一扫的那个框框的 起点坐标为 x y 宽为width 高为height ,deviceHeight ,deviceWidth指的是AVCaptureVideoPreviewLayer对象的高度，个人按这个方法弄但是有很多问题，效果不是很好。
／／个人觉得还是下面比较容易接受，与以往设置frame一样。
__weak typeof(self) weakSelf = self;
[[NSNotificationCenter defaultCenter]addObserverForName:AVCaptureInputPortFormatDescriptionDidChangeNotification object:nil queue:[NSOperationQueue mainQueue]
usingBlock:^(NSNotification * _Nonnull note) {
if (weakSelf){
AVCaptureMetadataOutput *output = session.outputs.firstObject;
output.rectOfInterest = [layer metadataOutputRectOfInterestForRect:CGRectMake(50, 100, 200, 200)];
}
}];
}
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection {
//判断是否有数据
if (metadataObjects != nil && [metadataObjects count] > 0) {
AVMetadataMachineReadableCodeObject *metadataObj = [metadataObjects objectAtIndex:0];
NSLog(@"=========%@",metadataObj.stringValue);
//判断回传的数据类型
if ([[metadataObj type] isEqualToString:AVMetadataObjectTypeQRCode]) {
}
}
}
