Incomplete sample of WPF ListView class

The sample code is typical of XAML/WPF samples. It is extremely, extremely frustrating. It does not show what EmployeeInfoDataSource is. It is so frustrating because there are so many ways of doing data binding and nearly always the actual definition and declaration of the data is not shown so it is very difficult to know what applies to what.

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#### Document Details

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* ID: 54a37aff-a0f4-98cf-7a5f-9d2193ee0462
* Version Independent ID: 7edf630c-d6a2-4ebd-7721-68e0fd350651
* Content: [ListView Class (System.Windows.Controls)](https://docs.microsoft.com/en-us/dotnet/api/system.windows.controls.listview?f1url=https%3A%2F%2Fmsdn.microsoft.com%2Fquery%2Fdev15.query%3FappId%3DDev15IDEF1%26l%3DEN-US%26k%3Dk(System.Windows.Controls.ListView);k(VS.XamlEditor);k(TargetFrameworkMoniker-.NETFramework,Version%3Dv4.6.1)%26rd%3Dtrue&view=netframework-4.7.2)
* Content Source: [xml/System.Windows.Controls/ListView.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Windows.Controls/ListView.xml)
* Product: **dotnet-api**
* GitHub Login: @dotnet-bot
* Microsoft Alias: **dotnetcontent**