Changing Frame Source and accessing function on another Page

 In a WPF page i had a frame control and on Click event of a button i am setting frame source and makes it visible. My main view is lilke this.

<Page   x:Class="MyApp.ViewMain"...............>
<Grid>
 <Button Name="ShowMetaDatas" ToolTip="Show Annotations, Bookmarks, Wordbank"  Click="ShowMetaDatas_Click"> </Button>
  <Border BorderBrush="Black" BorderThickness="2" CornerRadius="3" Height="600" Width="450" HorizontalAlignment="Right" VerticalAlignment="Top" Margin="0,5,20,0" Visibility="Collapsed" Name="metaDataSettings" Padding="10" Background="White" Opacity="2.0">
                <Grid>
                    <Button Name="CloseMetaDataWindow"  Click="CloseMetaDataWindow_Click" VerticalAlignment="Top" HorizontalAlignment="Right"  Style="{StaticResource ResourceKey=CircleButton}" Width="25" Height="25" Margin="0,0,5,0" Foreground="Red" ToolTip="Close">X</Button>
                    <Frame Name="metaDataFrame"  Height="600" Width="450"></Frame>
                </Grid>
     </Border>
</Grid>
</Page>

So on the click event of Show Meta Data i am loading a Page with data on to a Frame like this

    CustomDatas   metaChild = new CustomDatas("idofdata");
     metaDataFrame.Navigate(metaChild);

CustomDatas   page is like this

<Page x:Class="MyApp.CustomDatas"..........>
<Grid>
//Some control like grids and listviews that shows datas and a button is also present on the child page or on  the CustomDatas page
 <Button Name="btnPageAction" Click="btnPageAction_Click" />
</Grid>
</Page>

As a result my Frame inside the ViewMain page is filled with some datas.

TO DO
*------------------*
On btnPageAction_Click inside the frame i want to  Close the frame or set the frame source as null on ViewMain and pass some values to ViewMain -- Or simply want to call a function on ViewMain with some parameters from CustomDatas page . Is this possible? Then how can i do ? IS there any better aproach for doing it?

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