weex-30-如何使用扫码功能

var camera = weex.requireModule('camera')

camera.scanCode(res=>{
    if(res.result){
        this.show(res.data,1)
    }
})

#import "WXEventModule.h"
#import <WeexSDK/WeexSDK.h>
#import "WXCustomModule.h"
typedef   void (^CallBlock)(NSDictionary*); // 定义回调函数
@interface WXCameraModule :NSObject<WXModuleProtocol>
@end

 #import "WXCameraModule.h"
 #import "XJScanViewController.h"
  @implementation WXCameraModule
  @synthesize weexInstance; // 这个必须实现
// 把scanCode 方法暴露给weex,这部一定要做,否则weex将无法解析到js文件中的 camera 模块的scanCode 方法
WX_EXPORT_METHOD(@selector(scanCode:))

-(void)scanCode:(CallBlock)callback{
  // 下面这个是我定义的扫描二维码的原生类
  XJScanViewController *scanVC= [[XJScanViewController alloc]init];
// 将回调函数传递给scanVC 视图控制器,如果扫描到二维码将值传递给此闭包函数
 scanVC.callback = callback;
 [self.weexInstance.viewController.navigationController     presentViewController:scanVC animated:true completion:nil];
}
@end

 WXSDKEngine.registerModule("camera", with: WXCameraModule.self)

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

@interface XJScanViewController ()     <AVCaptureMetadataOutputObjectsDelegate>
@property (nonatomic, strong) AVCaptureSession * session;
@property (nonatomic, strong) AVCaptureVideoPreviewLayer *captureLayer;
@property (nonatomic, strong) UIView *sanFrameView;
@end

@implementation XJScanViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    [self setup];
}

-(void)setup{
  #if !(TARGET_IPHONE_SIMULATOR)
    self.session = [[AVCaptureSession alloc]init];
    [_session setSessionPreset:AVCaptureSessionPresetHigh];
    AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
    AVCaptureMetadataOutput * output = [[AVCaptureMetadataOutput alloc]init];
if (output && input && device) {
    [output setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
    [_session addInput:input];
    [_session addOutput:output];            
output.metadataObjectTypes=@[AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code];
}

_captureLayer = [AVCaptureVideoPreviewLayer layerWithSession:_session];
_captureLayer.videoGravity=AVLayerVideoGravityResizeAspectFill;
_captureLayer.frame=self.view.layer.bounds;
#endif

 [self.view.layer addSublayer:_captureLayer];
 UIButton *button = [[UIButton alloc]initWithFrame:CGRectMake(self.view.bounds.size.width/2-25, self.view.bounds.size.height-100, 50, 50)];
[button setBackgroundImage:[UIImage imageNamed:@"cancle.png"] forState:UIControlStateNormal];
[button addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button];
}

-(void)back{
   [self dismissViewControllerAnimated:true completion:nil];
}
- (void)captureOutput:(AVCaptureOutput *)captureOutput     didOutputMetadataObjects:(NSArray *)metadataObjects     fromConnection:(AVCaptureConnection *)connection
{
    [_captureLayer removeFromSuperlayer];
    [_session stopRunning];
    AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);
    if (metadataObjects.count > 0) {
        AVMetadataMachineReadableCodeObject * metadataObject = [metadataObjects objectAtIndex : 0 ];
        self.callback(@{@"result":@"true",@"data":metadataObject.stringValue});
        [self dismissViewControllerAnimated:true completion:nil];
    }
}
-(void)viewWillAppear:(BOOL)animated{
    [_session startRunning];
}
- (void)dealloc {
    [_captureLayer removeFromSuperlayer];
}