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    <p>Yes, you can do this, in as much as the code will work but there is a big potential issue you may run into in the future.</p> <p>One of the strong arguments for using the MVVM pattern is that it makes it easier to write code that can be easily tested.<br> With you're above code you can't test <code>ViewModel1</code> without also having <code>ViewModelLocator</code> and <code>ViewModel2</code>. May be that's not too much of a bad thing in and of itself but you've set a precedent that this type of strong coupling of classes is acceptable. What happens, in the future, when you </p> <p>From a testing perspective you would probably benefit from being able to inject your dependencies. This means passing, to the constructor--typically, the external objects of information you need.</p> <p>This could mean you have a constructor like this:</p> <pre><code>public ViewModel1(string vm2Name) { string name = vm2Name; } </code></pre> <p>that you call like this:</p> <pre><code>var vm1 = new ViewModel1(ViewModelLocator.ViewModel2.name); </code></pre> <p>There are few other issues you may want to consider also.</p> <p>You're also creating a new <code>ViewModelLocator</code> to access one of it's properties. You probably already have an instance of the locator defined at the application level. You're creating more work for yourself (and the processor) if you're newing up additional, unnecessary instances.</p> <p>Do you really need a complete instance of <code>ViewModel2</code> if all you need is the name? Avoid creating and passing more than you need to.</p> <p><strong>Update</strong></p> <p>If you capture the store in the first view/vm then why not pass that (ID &amp;/or Name) to the second VM from the second view? The second VM can then send that to the server with the data captured in the second view.</p> <p>Another approach may be to just use one viewmodel for both views. This may make your whole problem go away.</p>
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    1. POIs it bad to use ViewModelLocator to Grab other VM's for use in another Vm?
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    1. USMatt Lacey
    1. USMatt Lacey
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    1. COI see what you mean about testing as like you said not i always would have to create a dummy ViewModel1 and possibly the ViewModelLocator. I don't get your example where would that be? In the ViewModelLocator?
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    2. CO@chobo2 you'd use the example creation code wherever you're creating the ViewModel. (This may or may not be in the VML.)
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    3. COWell I am creating my Models in the ViewModel Locator using the built in IoC and then a property so not sure where to put that in. I added it to my OP. So you do not recommend messaging unless it is some sort of event you want to fire off and then forget about not something like passing fields back to another view to be used?
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