c# - Whats best practice to access Model inside Command in MVVM pattern in UWP app -

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lets have simple ui in mainpage.xaml

<listview itemsources="{binding records}" itemtemplate="{staticresource recordtemplate}"> </listview>

in app.xaml

<datatemplate x:key="recordtemplate">     <textblock text="{binding title}"/>     <button content="change title" command="{binding datacontext.changetitlecommand,          relativesource={relativesource ancestortype=listview}}"/> </datatemplate>

i want keep record class simple , clean possible, have 1 property title.

in mainviewmodel.cs, in changetitlecommand want access record model of listviewitem click on button.

i can cast sender object frameworkelement, access datacontext, cast record type , start making change. ugly , require viewmodel aware of view (frameworkelement), make viewmodel not reuseable in difference ui framework, want avoid approach.

one possibility bind command in record class, not in mainviewmodel (remove relativesource={relativesource ancestortype=listview}} part). way access model this keyword. way make record class become mess add more functions , event-to-command recordtemplate.

so best practice access model inside command ?

you can put template resources of mainpage.xaml , set command property following:

{binding changetitlecommand, source={staticresource viewmodelname}}.

or can set name page , write following: 

{binding datacontext.changetitlecommand, elementname='pagename'}

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