IOS打开系统相机的闪光灯

        [self presentModalViewController:picker  animated:YES];
        [picker release];
    }else{
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"你没有摄像头" delegate:nil cancelButtonTitle:@"Drat!" otherButtonTitles:nil];
        [alert show];
    }
}
//选中图片进入的代理方法
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo
{
    [self dismissModalViewControllerAnimated:YES];
}

 

调用闪光灯的代码，由于我也不是很理解，所以没法加注释，但是已经亲测可用，但是调闪光灯时有一个算是bug吧，闪光灯会闲一下，然后再一直亮

 

复制代码
-(void)openFlashlight
{
    AVCaptureDevice * device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if (device.torchMode == AVCaptureTorchModeOff) {
        //Create an AV session
        AVCaptureSession * session = [[AVCaptureSession alloc]init];
        // Create device input and add to current session
        AVCaptureDeviceInput * input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
        [session addInput:input];
        // Create video output and add to current session
        AVCaptureVideoDataOutput * output = [[AVCaptureVideoDataOutput alloc]init];
        [session addOutput:output];
        // Start session configuration
        [session beginConfiguration];
        [device lockForConfiguration:nil];
        // Set torch to on
        [device setTorchMode:AVCaptureTorchModeOn];
        [device unlockForConfiguration];
        [session commitConfiguration];
        // Start the session
        [session startRunning];
        // Keep the session around