c# - Sqlite Data not displaying -

application x:class="sqlasynctest.app" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="using:sqlasynctest" xmlns:viewmodel="using:sqlasynctest.viewmodel" requestedtheme="light"> <application.resources>     <resourcedictionary>         <viewmodel:viewmodellocator x:key="locator" />     </resourcedictionary> </application.resources> 

public class viewmodellocator {     public viewmodellocator()     {         servicelocator.setlocatorprovider(() => simpleioc.default);          if (!simpleioc.default.isregistered<idal>())         {             simpleioc.default.register<idal, dal>();         }           simpleioc.default.register<mainviewmodel>();     }     public mainviewmodel main     {                 {             return servicelocator.current.getinstance<mainviewmodel>();         }     }     public static void cleanup()     {         // todo clear viewmodels     }  } 

mainviewmodel

public class mainviewmodel : viewmodelbase {     private readonly idal _idal;      private ilist<user> _user;      public ilist<user> users     {         { return _user; }         set { set("users", ref _user, value); }     }     public mainviewmodel(idal dal)     {         _idal = dal;         loaddatacommand = new relaycommand(async () => await loaddata());     }     public icommand loaddatacommand { get; private set; }     public async task loaddata()     {         users = await _idal.loadalluser();     } } 

mainpage

<page x:class="sqlasynctest.mainpage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="using:sqlasynctest" datacontext="{binding main, source={staticresource locator}}" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:ignorable="d">  <grid background="{themeresource applicationpagebackgroundthemebrush}">     <grid.columndefinitions>         <columndefinition width="*"/>         <columndefinition width="20"/>         <columndefinition width="*"/>     </grid.columndefinitions>     <grid.rowdefinitions>         <rowdefinition height="140"/>         <rowdefinition height="*"/>     </grid.rowdefinitions>      <listbox grid.column="0" grid.row="1" selectionmode="single"              itemssource="{binding users}" margin="120,0,0,40">         <listbox.itemtemplate>             <datatemplate>                 <stackpanel orientation="horizontal">                     <textblock text="{binding firstname}"/>                     <textblock text="{binding lastname}"/>                 </stackpanel>             </datatemplate>         </listbox.itemtemplate>         </listbox> </grid> 

table , methods fine think binding wrong , me loaddata() method not called .

i got solution

protected override void onnavigatedto(navigationeventargs e)     {         var viewmodel = (mainviewmodel)datacontext;         if (viewmodel != null)         {             viewmodel.loaddata();         } 

i don't touch mainpage.cs other way in xaml code

you have loaddatacommand in view model, not called anywhere. there no magic here – have invoke either xaml, or code-behind file. here's way can done in xaml:

1. install microsoft.xaml.behaviors.uwp.managed nuget package.

2. modify xaml of main page:

   <page ... xmlns:i="using:microsoft.xaml.interactivity" xmlns:c="using:microsoft.xaml.interactions.core">   <i:interaction.behaviors>     <c:eventtriggerbehavior eventname="loaded">         <c:invokecommandaction command="{binding loaddatacommand}"/>     </c:eventtriggerbehavior> </i:interaction.behaviors>  <grid ...> 

3. remove overridden onnavigatedto method code-behind file.

4. loaddatacommand invoked each time mainpage loaded.