本篇文章主要介绍了"如何开发扫描二维码功能"，对于Windows Phone开发感兴趣的同学可以参考一下：
如何开发扫描二维码功能
随着 WinRT 8.1 API 的发布，Windows 8.1 和 Windows Phone 8.1 （基于 WinRT） 应用程序的开发模型经历了戏剧性的收敛性。与一些特定于平台的考虑，我们现在可以为 Windows 和使用几乎相同的 XAML 框架和 API 来开发 Windows Phone 开发应用程序。
"旧的"基于 Windows Phone 8.0 Silverlight API 将继续得到支持和改善，但基于 WinRT 的融合的模型显然是要在未来走的路。
所以抽时间实现了wp8.1实现二维码扫描的功能
1. 在项目中添加对Zxing的引用
Zxing示例代码下载地址:http://zxingnet.codeplex.com/
2.添加页面代码
<Grid x:Name="LayoutRoot" Background="Black"> <Grid Background="Black"> <Grid.ColumnDefinitions> <ColumnDefinition Width="50"/> <ColumnDefinition Width="300"/> <ColumnDefinition Width="50"/> Grid.ColumnDefinitions> <Grid Grid.Column="0" Height="366" Margin="0,0,0,0"> Grid> <Grid Grid.Column="1" x:Name="ScanViewGrid" Margin="0,0,0,0"> <Grid.Resources> <Storyboard x:Name="myStoryboard"> <DoubleAnimation Storyboard.TargetName="imgScan" Storyboard.TargetProperty="(Canvas.Top)" Duration="0:0:2.5" From="0" To="300" RepeatBehavior="Forever"/> Storyboard> Grid.Resources> <Canvas Width="300" Canvas.Top="170" Height="300"> <CaptureElement Stretch="UniformToFill" x:Name="VideoCapture" Width="300" Height="300" > CaptureElement> <Image x:Name="imgScan" Source="/Assets/img/light.png" Width="300" Height="40" Stretch="Fill"/> <Image x:Name="CaptureImage" Width="300" Height="300" Visibility="Collapsed" /> Canvas> Grid> <Grid Grid.Column="2" Margin="0,0,0,0"/> Grid> <TextBlock x:Name="Error" VerticalAlignment="Bottom" FontSize="32" Width="400" TextAlignment="Center" /> <TextBlock x:Name="ScanResult" Text="hhh" FontSize="25" Foreground="White" VerticalAlignment="Bottom" TextAlignment="Center" Width="400"/> Grid>
3.功能实现
public sealed partial class QCodeView : Page
{ private readonly MediaCapture _mediaCapture = new MediaCapture(); private Result _result; private NavigationHelper navigationHelper; private ObservableDictionary defaultViewModel = new ObservableDictionary(); private DispatcherTimer _timer; public QCodeView()
{ this.InitializeComponent(); //设备屏幕方向 DisplayInformation.AutoRotationPreferences = DisplayOrientations.Portrait; ///隐藏StatusBar var statusBar = StatusBar.GetForCurrentView();
statusBar.HideAsync(); this.navigationHelper = new NavigationHelper(this); this.navigationHelper.LoadState += this.NavigationHelper_LoadState; this.navigationHelper.SaveState += this.NavigationHelper_SaveState;
} /// /// 获取与此 关联的 。 /// public NavigationHelper NavigationHelper
{ get { return this.navigationHelper; }
} /// /// 获取此 的视图模型。 /// 可将其更改为强类型视图模型。 /// public ObservableDictionary DefaultViewModel
{ get { return this.defaultViewModel; }
} /// /// 使用在导航过程中传递的内容填充页。 在从以前的会话 /// 重新创建页时，也会提供任何已保存状态。 /// /// /// 事件的来源; 通常为 /// /// 事件数据，其中既提供在最初请求此页时传递给 /// 的导航参数，又提供 /// 此页在以前会话期间保留的状态的 /// 字典。 首次访问页面时，该状态将为 null。 private void NavigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
} /// /// 保留与此页关联的状态，以防挂起应用程序或 /// 从导航缓存中放弃此页。值必须符合 /// 的序列化要求。 /// /// 事件的来源；通常为 ///提供要使用可序列化状态填充的空字典 ///的事件数据。 private void NavigationHelper_SaveState(object sender, SaveStateEventArgs e)
{
} #region NavigationHelper 注册 /// /// 此部分中提供的方法只是用于使 /// NavigationHelper 可响应页面的导航方法。 /// /// 应将页面特有的逻辑放入用于 /// /// 和 的事件处理程序中。 /// 除了在会话期间保留的页面状态之外 /// LoadState 方法中还提供导航参数。 /// /// /// 提供导航方法数据和 /// 无法取消导航请求的事件处理程序。 protected override void OnNavigatedTo(NavigationEventArgs e)
{
myStoryboard.Begin();
InitVideoCapture();
InitVideoTimer(); this.navigationHelper.OnNavigatedTo(e);
} /// /// 初始化摄像 /// private async void InitVideoCapture()
{ ///摄像头的检测 var cameras = await DeviceInformation.FindAllAsync(DeviceClass.VideoCapture); if (cameras.Count < 1)
{
Error.Text = "设备没有摄像头,读取本地资源"; await DecodeStaticResource(); return;
} /// 创建 MediaCaptureInitializationSettings 对象的新实例。 var settings = new MediaCaptureInitializationSettings
{
StreamingCaptureMode = StreamingCaptureMode.AudioAndVideo,
MediaCategory = MediaCategory.Other,
AudioProcessing = Windows.Media.AudioProcessing.Default,
VideoDeviceId = cameras[1].Id
}; //if (cameras.Count == 1) //{ // settings = new MediaCaptureInitializationSettings { VideoDeviceId = cameras[0].Id }; // 0 => front, 1 => back //} //else //{ // settings = new MediaCaptureInitializationSettings { VideoDeviceId = cameras[1].Id }; // 0 => front, 1 => back //} await _mediaCapture.InitializeAsync(settings);
VideoCapture.Source = _mediaCapture; await _mediaCapture.StartPreviewAsync();
} private void InitVideoTimer()
{
_timer = new DispatcherTimer();
_timer.Interval = TimeSpan.FromSeconds(6);
_timer.Tick += _timer_Tick;
_timer.Start();
} private bool IsBusy = false; async void _timer_Tick(object sender, object e)
{ try { while (_result == null)
{ if (!IsBusy)
{
IsBusy = true; ///获取焦点 //var autoFocusSupported = _mediaCapture.VideoDeviceController.FocusControl.SupportedFocusModes.Contains(FocusMode.Auto); //if (autoFocusSupported) //{ // var focusSettings = new FocusSettings // { // Mode = FocusMode.Auto, // AutoFocusRange = AutoFocusRange.Normal // }; // _mediaCapture.VideoDeviceController.FocusControl.Configure(focusSettings); // //await _mediaCapture.VideoDeviceController.FocusControl.FocusAsync().AsTask(_cancellationTokenSource.Token); //} var photoStorageFile = await KnownFolders.PicturesLibrary.CreateFileAsync("qcode.jpg", CreationCollisionOption.ReplaceExisting); await _mediaCapture.CapturePhotoToStorageFileAsync(ImageEncodingProperties.CreateJpeg(), photoStorageFile); var stream = await photoStorageFile.OpenReadAsync(); // initialize with 1,1 to get the current size of the image var writeableBmp = new WriteableBitmap(1, 1);
writeableBmp.SetSource(stream); // and create it again because otherwise the WB isn't fully initialized and decoding // results in a IndexOutOfRange writeableBmp = new WriteableBitmap(writeableBmp.PixelWidth, writeableBmp.PixelHeight);
stream.Seek(0);
writeableBmp.SetSource(stream);
_result = ScanBitmap(writeableBmp); await photoStorageFile.DeleteAsync(StorageDeleteOption.PermanentDelete);
} if (_result != null)
{ await _mediaCapture.StopPreviewAsync();
VideoCapture.Visibility = Visibility.Collapsed;
CaptureImage.Visibility = Visibility.Visible;
ScanResult.Text = _result.Text;
_timer.Stop();
myStoryboard.Stop();
imgScan.Visibility = Visibility.Collapsed;
}
IsBusy = false;
}
} catch (Exception ex)
{
IsBusy = false; //Error.Text = ex.Message; }
} /// /// 读取本地资源 /// /// private async System.Threading.Tasks.Task DecodeStaticResource()
{ var file = await Windows.ApplicationModel.Package.Current.InstalledLocation.GetFileAsync(@"Assets\1.png"); var stream = await file.OpenReadAsync(); // initialize with 1,1 to get the current size of the image var writeableBmp = new WriteableBitmap(1, 1);
writeableBmp.SetSource(stream); // and create it again because otherwise the WB isn't fully initialized and decoding // results in a IndexOutOfRange writeableBmp = new WriteableBitmap(writeableBmp.PixelWidth, writeableBmp.PixelHeight);
stream.Seek(0);
writeableBmp.SetSource(stream);
CaptureImage.Source = writeableBmp;
VideoCapture.Visibility = Visibility.Collapsed;
CaptureImage.Visibility = Visibility.Visible;
_result = ScanBitmap(writeableBmp); if (_result != null)
{
ScanResult.Text += _result.Text;
} return;
} /// /// 解析二维码图片 /// /// 拍摄的图片 /// private Result ScanBitmap(WriteableBitmap writeableBmp)
{ var barcodeReader = new BarcodeReader
{
TryHarder = true,
AutoRotate = true }; var result = barcodeReader.Decode(writeableBmp); if (result != null)
{
CaptureImage.Source = writeableBmp;
} return result;
} /// /// 页面离开时对_mediaCapture对象进行释放 /// 防止内存溢出及资源占用 /// /// protected override async void OnNavigatedFrom(NavigationEventArgs e)
{ try { await _mediaCapture.StopPreviewAsync(); await _mediaCapture.StopRecordAsync();
_mediaCapture.Dispose();
} catch (Exception)
{
} this.navigationHelper.OnNavigatedFrom(e);
} #endregion }
源码下载地址:http://vdisk.weibo.com/s/ztJnMX2jYqaK3
注意事项: 在调试时如果出现死机现象 ，请长按锁屏键+音量（-）键 方可重启手机。
以上就介绍了如何开发扫描二维码功能，包括了方面的内容，希望对Windows Phone开发有兴趣的朋友有所帮助。
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