iOS 二维码生成及扫码详解及实例代码

/** 
 * @author 半  饱, 15-12-18 
 * 
 * @brief 生成二维码图片 
 * 
 * @param code  生成二维码图片内容 
 * @param width 二维码图片宽度 
 * @param height 二维码图片高度 
 * 
 * @return 返回uiimage对象 
 */ 
- (uiimage *)generateqrcode:(nsstring *)code width:(cgfloat)width height:(cgfloat)height { 
  ciimage *qrcodeimage; 
  nsdata *data = [code datausingencoding:nsisolatin1stringencoding allowlossyconversion:false]; 
  cifilter *filter = [cifilter filterwithname:@"ciqrcodegenerator"]; 
   
  [filter setvalue:data forkey:@"inputmessage"]; 
  [filter setvalue:@"h" forkey:@"inputcorrectionlevel"]; 
  qrcodeimage = [filter outputimage]; 
   
  cgfloat scalex = width / qrcodeimage.extent.size.width; 
  cgfloat scaley = height / qrcodeimage.extent.size.height; 
  ciimage *transformedimage = [qrcodeimage imagebyapplyingtransform:cgaffinetransformscale(cgaffinetransformidentity, scalex, scaley)]; 
   
  return [uiimage imagewithciimage:transformedimage]; 
} 

#import <avfoundation/avfoundation.h> 
 
static const float lightwidth = 240.f; 
static const float lightheight = 240.f; 
static const float crosslinewidth = 2.f; 
static const float crosslineheight = 15.f; 
 
@interface bbscancodeviewcontroller ()<avcapturemetadataoutputobjectsdelegate> { 
  float leftwith; 
  float topheight; 
} 
@property (strong , nonatomic ) avcapturedevice *capturedevice; 
@property (strong , nonatomic ) avcapturedeviceinput *captureinput; 
@property (strong , nonatomic ) avcapturemetadataoutput *captureoutput; 
@property (strong , nonatomic ) avcapturesession *capturesession; 
@property (strong , nonatomic ) avcapturevideopreviewlayer *capturepreview; 
 
@property (strong,nonatomic) uibutton *flashlightbtn; 
@property (strong,nonatomic) uiimageview *lineimageview; 
 
@end 
 
@implementation bbscancodeviewcontroller 
@synthesize capturedevice = _capturedevice; 
@synthesize captureinput = _captureinput; 
@synthesize captureoutput = _captureoutput; 
@synthesize capturepreview = _capturepreview; 
@synthesize capturesession = _capturesession; 
@synthesize delegate = _delegate; 
@synthesize isrectscan = _isrectscan; 
@synthesize lineimageview = _lineimageview; 
@synthesize flashlightbtn = _flashlightbtn; 
- (void)viewdidload { 
   
  [super viewdidload]; 
  self.isshownavigationitem = yes; 
  cgrect screenrect = [uiscreen mainscreen].bounds; 
  leftwith = (screenrect.size.width - lightwidth) / 2; 
  topheight =(screenrect.size.height - lightheight) / 2; 
   
#if !target_iphone_simulator 
  [self initscancode]; 
#endif 
  [self initlayer]; 
  [self initviewcontrol]; 
   
   
 
  [[nsnotificationcenter defaultcenter] addobserver:self selector:@selector(willresignactivenotification) name:uiapplicationwillresignactivenotification object:nil]; //监听是否触发home键挂起程序. 
  [[nsnotificationcenter defaultcenter] addobserver:self selector:@selector(didbecomeactivenotification) name:uiapplicationdidbecomeactivenotification object:nil]; //监听是否重新进入程序程序. 
} 
 
-(void)viewwilldisappear:(bool)animated { 
   [self stopscancode]; 
  [super viewwilldisappear:animated]; 
} 
 
- (void)willresignactivenotification { 
  _flashlightbtn.selected = no; 
} 
- (void)didbecomeactivenotification { 
 
} 
//加载界面上的控件，如：加上闪光灯按钮等 
- (void)initviewcontrol { 
 
  @autoreleasepool { 
    _flashlightbtn = [uibutton buttonwithtype:uibuttontypecustom]; 
    [_flashlightbtn setimage:[uiimage imagenamed:@"openflashlight.png"] forstate:uicontrolstatenormal]; 
    [_flashlightbtn setimage:[uiimage imagenamed:@"closeflashlight.png"] forstate:uicontrolstateselected]; 
    _flashlightbtn.frame = cgrectmake(leftwith, 80.f, 30.f, 30.f); 
    [_flashlightbtn addtarget:self action:@selector(systemflashlight) forcontrolevents:uicontroleventtouchupinside]; 
    [self.view addsubview:_flashlightbtn]; 
     
    _lineimageview = [[uiimageview alloc] initwithimage:nil]; 
    _lineimageview.backgroundcolor = [uicolor greencolor]; 
    _lineimageview.frame = cgrectmake(leftwith, topheight, lightwidth, 2); 
    [self.view addsubview:_lineimageview]; 
    [self scanlineanimation]; 
  } 
   
} 
 
- (void)scanlineanimation { 
  [uiview beginanimations:nil context:nil]; 
  [uiview setanimationduration:4.f]; 
  //设置代理 
  [uiview setanimationdelegate:self]; 
  //设置动画执行完毕调用的事件 
  [uiview setanimationdidstopselector:@selector(didviewanimation)]; 
  _lineimageview.frame = cgrectmake(leftwith,topheight + lightheight-2,lightwidth,2); 
  [uiview commitanimations]; 
 
} 
 
-(void)didviewanimation { 
//  self.navigationcontroller 
  _lineimageview.frame = cgrectmake(leftwith, topheight, lightwidth, 2); 
  [self scanlineanimation]; 
} 
 
- (void)insertlayerwithframe:(cgrect)frame withbackgroundcolor:(uicolor *)backgroundcolor { 
  @autoreleasepool { 
    calayer *layer = [calayer layer]; 
    layer.backgroundcolor = backgroundcolor.cgcolor; 
    layer.frame = frame; 
    [self.view.layer addsublayer:layer]; 
  } 
} 
//初始化layer层，绘制半透明区域 
-(void) initlayer { 
  //公共参数 
  uicolor *fillcolor = [uicolor colorwithred:0xae/255.f green:0xae/255.f blue:0xae/255.f alpha:0.4]; 
  uicolor *crosscolor = [uicolor greencolor]; 
  cgrect screenrect = [uiscreen mainscreen].bounds; 
  [self insertlayerwithframe:cgrectmake(0, 0, leftwith, screenrect.size.height) withbackgroundcolor:fillcolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith, 0, lightwidth, topheight) withbackgroundcolor:fillcolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith + lightwidth, 0, leftwith, screenrect.size.height) withbackgroundcolor:fillcolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith, topheight + lightheight, lightwidth, topheight) withbackgroundcolor:fillcolor]; 
   
   
  [self insertlayerwithframe:cgrectmake(leftwith, topheight, crosslinewidth, crosslineheight) withbackgroundcolor:crosscolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith, topheight, crosslineheight, crosslinewidth) withbackgroundcolor:crosscolor]; 
   
  [self insertlayerwithframe:cgrectmake(leftwith + lightwidth - crosslineheight, topheight, crosslineheight, crosslinewidth) withbackgroundcolor:crosscolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith + lightwidth - crosslinewidth, topheight, crosslinewidth, crosslineheight) withbackgroundcolor:crosscolor]; 
   
  [self insertlayerwithframe:cgrectmake(leftwith, topheight + lightheight - crosslineheight, crosslinewidth, crosslineheight) withbackgroundcolor:crosscolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith, topheight + lightheight - crosslinewidth, crosslineheight, crosslinewidth) withbackgroundcolor:crosscolor]; 
   
  [self insertlayerwithframe:cgrectmake(leftwith + lightwidth - crosslineheight, topheight + lightheight - crosslinewidth, crosslineheight, crosslinewidth) withbackgroundcolor:crosscolor]; 
  [self insertlayerwithframe:cgrectmake(leftwith + lightwidth - crosslinewidth, topheight + lightheight - crosslineheight, crosslinewidth, crosslineheight) withbackgroundcolor:crosscolor]; 
} 
 
-(void)initscancode { 
  @autoreleasepool { 
    _capturedevice = [ avcapturedevice defaultdevicewithmediatype : avmediatypevideo]; 
    _captureinput = [ avcapturedeviceinput deviceinputwithdevice : _capturedevice error : nil ]; 
    _captureoutput = [[ avcapturemetadataoutput alloc ] init ]; 
    [_captureoutput setmetadataobjectsdelegate : self queue : dispatch_get_main_queue ()]; 
    if (_isrectscan) { 
      cgrect screenrect = [uiscreen mainscreen].bounds; 
      [ _captureoutput setrectofinterest : cgrectmake (topheight / screenrect.size.height, leftwith / screenrect.size.width, lightheight/screenrect.size.height, lightwidth / screenrect.size.width)]; 
    } 
 
    _capturesession = [[ avcapturesession alloc ] init ]; 
    [_capturesession setsessionpreset : avcapturesessionpresethigh ]; 
    if ([_capturesession canaddinput : _captureinput ]) 
    { 
      [_capturesession addinput : _captureinput ]; 
    } 
    if ([_capturesession canaddoutput : _captureoutput ]) 
    { 
      [_capturesession addoutput : _captureoutput ]; 
    } 
    _captureoutput.metadataobjecttypes = @[avmetadataobjecttypeqrcode ] ; 
     
    _capturepreview =[ avcapturevideopreviewlayer layerwithsession :_capturesession ]; 
    _capturepreview.videogravity = avlayervideogravityresizeaspectfill ; 
    _capturepreview.frame = self.view.layer.bounds ; 
    [self.view.layer insertsublayer : _capturepreview atindex : 0 ]; 
    [_capturesession startrunning ]; 
  } 
} 
 
- ( void )captureoutput:( avcaptureoutput *)captureoutput didoutputmetadataobjects:( nsarray *)metadataobjects fromconnection:( avcaptureconnection *)connection 
{ 
  if (metadataobjects != nil && [metadataobjects count] > 0) { 
    avmetadatamachinereadablecodeobject *metadataobj = [metadataobjects objectatindex:0]; 
    nsstring *scancoderesult; 
    if ([[metadataobj type] isequaltostring:avmetadataobjecttypeqrcode]) { 
      [self stopscancode]; 
      scancoderesult = metadataobj.stringvalue; 
      //回调信息 
      if (_delegate && [_delegate respondstoselector:@selector(scancoderesultbyviewcontroller:withscancoderesult:)]) { 
        [_delegate scancoderesultbyviewcontroller:self withscancoderesult:scancoderesult]; 
        [self.navigationcontroller popviewcontrolleranimated:yes]; 
      } 
    } else { 
      nslog(@"扫描信息错误！"); 
    } 
  } 
} 
 
- (void)systemflashlight 
{ 
#if !target_iphone_simulator 
  if([_capturedevice hastorch] && [self.capturedevice hasflash]) 
  { 
    [_capturesession beginconfiguration]; 
    [_capturedevice lockforconfiguration:nil]; 
    if(_capturedevice.torchmode == avcapturetorchmodeoff) 
    { 
      _flashlightbtn.selected = yes; 
      [_capturedevice settorchmode:avcapturetorchmodeon]; 
      [_capturedevice setflashmode:avcaptureflashmodeon]; 
    } 
    else { 
      _flashlightbtn.selected = no; 
      [_capturedevice settorchmode:avcapturetorchmodeoff]; 
      [_capturedevice setflashmode:avcaptureflashmodeoff]; 
    } 
    [_capturedevice unlockforconfiguration]; 
    [_capturesession commitconfiguration]; 
  } 
#else 
  [commonutil showalert:g_alerttitle withmessage:@"虚拟设备不能运行摄像头！"]; 
#endif 
} 
 
-(void)stopscancode { 
  [_capturesession stoprunning]; 
  _capturesession = nil; 
  _capturedevice = nil; 
  _captureinput = nil; 
  _captureoutput = nil; 
  [_capturepreview removefromsuperlayer]; 
} 
 
- (void)didreceivememorywarning { 
  [super didreceivememorywarning]; 
} 
 
@end