tweaks of the display styles

Author: xieguigang

src/viewers/HDSViewer/DataViewer/FormHtmlViewer.vb

@@ -1,13 +1,30 @@
 Imports Galaxy.Workbench
+Imports Microsoft.Web.WebView2.Core
 
 Public Class FormHtmlViewer
 
+    Dim html_str As String
+    Dim initialized As Boolean = False
+
     Private Async Sub FormHtmlViewer_Load(sender As Object, e As EventArgs) Handles Me.Load
         Await WebViewLoader.Init(WebView21)
     End Sub
 
+    Private Sub WebView21_CoreWebView2InitializationCompleted(sender As Object, e As CoreWebView2InitializationCompletedEventArgs) Handles WebView21.CoreWebView2InitializationCompleted
+        initialized = True
+
+        If Not html_str Is Nothing Then
+            Call WebViewLoader.NavigateToLargeString(WebView21, html_str)
+        End If
+    End Sub
+
     Public Function ViewHtml(html As String) As FormHtmlViewer
-        Call WebViewLoader.NavigateToLargeString(WebView21, html)
+        html_str = html
+
+        If initialized Then
+            Call WebViewLoader.NavigateToLargeString(WebView21, html_str)
+        End If
+
         Return Me
     End Function
 End Class