IOSのオープンシステム懐中電灯

最初にヘッダファイルをインポート

#import 

そして

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    button.frame = CGRectMake(20, 40, 200, 40);
    button.center = self.view.center;
    button.backgroundColor = [UIColor redColor];
    [button setTitle:@" " forState:UIControlStateNormal];
    [button setTitle:@" " forState:UIControlStateSelected];
    [button addTarget:self action:@selector(clickButton:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];

クリックイベント

-(void)clickButton:(UIButton *)button{

        AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    // 
        if ([device hasTorch] && [device hasFlash]){
            
            [device lockForConfiguration:nil];
            button.selected = !button.selected;
            if (button.selected) {
                [device setTorchMode:AVCaptureTorchModeOn];
                [device setFlashMode:AVCaptureFlashModeOn];
                
            } else {
                [device setTorchMode:AVCaptureTorchModeOff];
                [device setFlashMode:AVCaptureFlashModeOff];
                
            }
            [device unlockForConfiguration];
        }
    
}

END.