Optimize and improve QR code display

v2rayN/v2rayN.Desktop/Views/QrcodeView.axaml

@@ -4,19 +4,25 @@
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
-    d:DesignHeight="480"
-    d:DesignWidth="400"
+    xmlns:sys="clr-namespace:System;assembly=netstandard"
+    d:DesignHeight="600"
+    d:DesignWidth="600"
     mc:Ignorable="d">
+
+    <UserControl.Resources>
+        <sys:Double x:Key="QrcodeWidth">500</sys:Double>
+    </UserControl.Resources>
+
     <Grid Margin="32" RowDefinitions="Auto,Auto">
         <Image
             Name="imgQrcode"
-            Width="300"
-            Height="300" />
+            Width="{StaticResource QrcodeWidth}"
+            Height="{StaticResource QrcodeWidth}" />
 
         <TextBox
             x:Name="txtContent"
             Grid.Row="1"
-            Width="300"
+            Width="{StaticResource QrcodeWidth}"
             MaxHeight="100"
             Margin="{StaticResource MarginTb8}"
             VerticalAlignment="Center"

v2rayN/v2rayN.Desktop/Views/QrcodeView.axaml.cs

@@ -23,8 +23,16 @@ public partial class QrcodeView : UserControl
 
     private Bitmap? GetQRCode(string? url)
     {
-        var bytes = QRCodeUtils.GenQRCode(url);
-        return ByteToBitmap(bytes);
+        try
+        {
+            var bytes = QRCodeUtils.GenQRCode(url);
+            return ByteToBitmap(bytes);
+        }
+        catch (Exception ex)
+        {
+            Logging.SaveLog("GetQRCode", ex);
+            return null;
+        }
     }
 
     private Bitmap? ByteToBitmap(byte[]? bytes)