如何在 Xamarin 窗体中 ZXing.Net 扫描程序与其他 UI 元素一起使用?

Question

我正在查看 Xamarin.Forms 的 ZXing.net 示例，它使用纯代码方法来扫描条形码。

我用这个问题作为灵感来获得以下代码，但是 我不完全确定在使用 Prism 时如何管理扫描事件。

<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms" 
xmlns:zx="clr-namespace:ZXing.Net.Mobile.Forms;assembly=ZXing.Net.Mobile.Forms"
xmlns:zxcm="clr-namespace:ZXing.Common;assembly=zxing.portable"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="WebOfTrust.Views.Client.MyPeople.ScanNewOrUpdateContact">
<ContentPage.Content>
<StackLayout>

<zx:ZXingDefaultOverlay
TopText= " Hold your phone up to the barcode"
BottomText=" Scanning will being automatically">
</zx:ZXingDefaultOverlay>

<!--     BarcodeValue="{Binding QrCode}"    -->
<zx:ZXingScannerView
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand"> 
</zx:ZXingScannerView>
</StackLayout>
</ContentPage.Content>
</ContentPage>

我的问题是，如何设计一个页面，以便我可以捕获 OnScanResult，如示例中所示(复制如下(

zxing.OnScanResult += (result) => 
Device.BeginInvokeOnMainThread (async () => {
// Stop analysis until we navigate away so we don't keep reading barcodes
zxing.IsAnalyzing = false;
// Show an alert
await DisplayAlert ("Scanned Barcode", result.Text, "OK");
// Navigate away
await Navigation.PopAsync ();
});

Answer 1

请参考以下代码：

在 XAML 中

<zx:ZXingScannerView
x:Name="zxing"
IsAnalyzing="{Binding IsAnalyzing,Mode=TwoWay}" 
Result="{Binding Result, Mode=TwoWay}"
ScanResultCommand="{Binding ScanResultCommand}"                
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand"> 
</zx:ZXingScannerView> 

在视图中模型

public ZXing.Result Result { get; set; }
public bool IsAnalyzing { get;set }
public Command ScanResultCommand
{
get
{
return new Command(() =>
{
Device.BeginInvokeOnMainThread(async () =>
{
IsAnalyzing = false;
Console.WriteLine(Result.Text);
//...
});
});
}
}