How to access methods of a view element in viewmodel?

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C#

WPF

MVVM

I have used the following code to turn the UI event into a command:

<i:Interaction.Triggers>
        <i:EventTrigger EventName="OnDemandLoading" SourceObject="{Binding ElementName=dataPager}">
            <i:InvokeCommandAction Command="{Binding DataGridContext}" PassEventArgsToCommand="True"/>
        </i:EventTrigger>
</i:Interaction.Triggers>

It can run a method in ViewModel when the related event is raised. I need to have access to all methods of control. For example, dataPager has a method called LoadDynamicItems() and I want to access it in ViewModel. How is this possible?

What I have tried:

I have no idea about solving this problem.