iOSQRCode(二維碼)

實現思路

1. 輸入裝置(用來獲取外界資訊) 攝像頭, 麥克風, 鍵盤
2. 輸出裝置 (將收集到的資訊, 做解析, 來獲取收到的內容)
3. 會話session (用來連線輸入和輸出裝置)
4. 特殊的layer (展示輸入裝置所採集的資訊)

1. 導包

#import <AVFoundation/AVFoundation.h>

2. 程式碼

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>

@interface ViewController ()<AVCaptureMetadataOutputObjectsDelegate>
//1. 輸入裝置(用來獲取外界資訊)  攝像頭, 麥克風, 鍵盤
@property (nonatomic, strong) AVCaptureDeviceInput *input;
//2. 輸出裝置 (將收集到的資訊, 做解析, 來獲取收到的內容)
@property (nonatomic, strong) AVCaptureMetadataOutput *output;
//3. 會話session (用來連線輸入和輸出裝置)
@property (nonatomic, strong) AVCaptureSession *session;
//4. 特殊的layer (展示輸入裝置所採集的資訊)
@property (nonatomic, strong) AVCaptureVideoPreviewLayer *previewLayer;
@end

@implementation ViewController

#pragma mark 點選螢幕開始掃描
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
    //1.輸入裝置(用來獲取外界資訊)  攝像頭, 麥克風, 鍵盤
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    self.input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
    
    //2.輸出裝置 (將收集到的資訊, 做解析, 來獲取收到的內容)
    self.output = [AVCaptureMetadataOutput new];
    
    //3.會話session (用來連線輸入和輸出裝置)
    self.session = [AVCaptureSession new];
    
    // 會話掃描展示的大小
    [self.session setSessionPreset:AVCaptureSessionPresetHigh];
    
    // 會話跟輸入和輸出裝置關聯
    if ([self.session canAddInput:self.input]) {
        [self.session addInput:self.input];
    }
    if ([self.session canAddOutput:self.output]) {
         [self.session addOutput:self.output];
    }
    
    //下面兩句程式碼應該寫在此處
    //制定輸出裝置的代理, 用來接受返回的資料
    [self.output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
    
    //設定後設資料型別 二維碼QRCode
    [self.output setMetadataObjectTypes:@[AVMetadataObjectTypeQRCode]];
    
    //4.特殊的layer (展示輸入裝置所採集的資訊)
    self.previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.session];
    // 大小layer的大小
    self.previewLayer.frame = self.view.bounds;
    [self.view.layer addSublayer:self.previewLayer];
    
    //5. 啟動會話
    [self.session startRunning];
}

/**
 captureOutput : 輸出裝置
 metadataObjects : 後設資料物件的陣列
 connection : 連線
 */
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection
{
    //1. 停止會話
    [self.session stopRunning];
    
    //2. 刪除layer
    [self.previewLayer removeFromSuperlayer];
    
    //3. 遍歷資料獲取內容
    for (AVMetadataMachineReadableCodeObject *obj in metadataObjects) {
        NSLog(@"obj: %@",obj.stringValue);
    }
}

@end