为什么在.net毛伊岛显示黑色屏幕？

Question

我正在尝试使用来自https://github.com/Redth/ZXing.Net.Maui的条形码扫描https://github.com/Redth/ZXing.Net.Maui

我将扫描仪添加到页面中，如下所示：

    <?xml version="1.0" encoding="utf-8" ?>
    <ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
                 xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
                 x:Class="myapp.Pages.ControleDesBillets"
                 x:DataType="viewmodel:StandardPageVM"
                 xmlns:viewmodel="clr-namespace:myapp.ViewModels"
                 xmlns:Controls="clr-namespace:myapp.Resources.Controls"             
                 xmlns:zxing="clr-namespace:ZXing.Net.Maui.Controls;assembly=ZXing.Net.MAUI">

        <Grid RowDefinitions="*" ColumnDefinitions="*">
            <zxing:CameraBarcodeReaderView x:Name="cameraBarcodeReaderView" Grid.Column="0" Grid.Row="0" HeightRequest="200" WidthRequest="200"/>
        </Grid>

    </ContentPage>

当应用程序运行时，它会提示进入摄像头，这是允许的，然后它会显示一个黑色的屏幕，没有其他任何东西。

在应用程序的启动过程中，扫描仪被初始化：

    public static MauiApp CreateMauiApp()
    {
        var builder = MauiApp.CreateBuilder();

        builder.UseMauiApp<App>().UseMauiCommunityToolkit();
        builder.UseBarcodeReader();  // << here
        return builder.Build();
    }       

我在用物理设备测试。这是我的输出：

    Loaded assembly: /data/data/com.companyname.myapp/files/.__override__/Xamarin.Google.Guava.ListenableFuture.dll [External]
    [CameraManagerGlobal] Connecting to camera service
    [CameraManagerGlobal] [soar.cts] ignore the status update of camera: 2
    [CameraManagerGlobal] [soar.cts] ignore the status update of camera: 3
    [CameraManagerGlobal] [soar.cts] ignore the status update of camera: 4
    [CameraManagerGlobal] [soar.cts] ignore the status update of camera: 5
    [CameraManagerGlobal] ignore the torch status update of camera: 3
    [CameraManagerGlobal] ignore the torch status update of camera: 4
    [CameraMetadataJV] setAppNameAndSensorId all [com.antutu:0,ssize,12032x9024,0,false]
    [CameraMetadataJV] setAppNameAndSensorId all [com.antutu:1,ssize,5184x3880,0,false]
    [CameraRepository] Added camera: 0
    [Camera2CameraInfo] Device Level: INFO_SUPPORTED_HARDWARE_LEVEL_3
    [CameraRepository] Added camera: 1
    [Camera2CameraInfo] Device Level: INFO_SUPPORTED_HARDWARE_LEVEL_3
    [CameraValidator] Verifying camera lens facing on rain, lensFacingInteger: null
    Thread finished: <Thread Pool> #2
    Thread finished: <Thread Pool> #4
    Le thread 0x2 s'est arrêté avec le code 0 (0x0).
    Le thread 0x4 s'est arrêté avec le code 0 (0x0).
    [CompatibilityChangeReporter] Compat change id reported: 150939131; UID 10378; state: ENABLED

有人知道我做错了什么吗？

谢谢。干杯,

Answer 1

这是一个众所周知的问题：https://github.com/Redth/ZXing.Net.Maui/issues/7

无论是XF还是毛伊岛，都一直是垃圾。它要么速度慢，性能差，要么存在随机问题，而且几乎没有好的特性。

还有一个基于BarcodeScanner的MLKit，这与我前面提到的截然相反。

这里的安装步骤：https://github.com/JimmyPun610/BarcodeScanner.Mobile/wiki/3.-Installation-for-Maui

一旦您安装了它并准备好了基本的设置，您所要做的就是如下所示：

 <ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="SampleApp.Maui.Page1"
             xmlns:gv="clr-namespace:BarcodeScanner.Mobile.Maui;assembly=BarcodeScanner.Mobile.Maui"
             Title="Page1">
   <ContentPage.Content>
     <!--VirbationOnDetected: Indicate the device will vibrate or not when detected barcode, default is True
         TorchOn: Indicate the torch will on or not when the view appear, default is False
         IsScanning : Indicate whether the device will start scanning after it is opened, default is True
         RequestedFPS: Affect Android only, remove it if you want a default value (https://developers.google.com/android/reference/com/google/android/gms/vision/CameraSource.Builder.html#public-camerasource.builder-setrequestedfps-float-fps)
         ScanInterval: Scan interval for iOS, default is 500ms and the minimum is 100ms, please be reminded that double scanning may be occurred if it is too small
         -->
          <gv:CameraView HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" OnDetected="CameraView_OnDetected" Grid.Row="1"
                           TorchOn="False" VibrationOnDetected="False" ScanInterval="50" x:Name="Camera"/>

   </ContentPage.Content>
</ContentPage>

你就完蛋了。希望这能有所帮助！

Answer 2

当我按下带有摄像头视图的页面，用NavigationPage包起来，它就会结冰。

await Shell.Current.Navigation.PushModalAsync(new NavigaionPage(new ScannerPage), false);

但是推送页面本身就很好，没有问题。

await Shell.Current.Navigation.PushModalAsync(new ScannerPage(), false);