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POA list of, list of ObservableCollection<Image> comes up null when looping through it
 

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  1. POA list of, list of ObservableCollection<Image> comes up null when looping through it
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    <p>I have a collection of collection that's setup like the following.</p> <pre><code>ObservableCollection&lt;ObservableCollection&lt;Image&gt;&gt; _Documents_CompleteClaims= new ObservableCollection&lt;ObservableCollection&lt;Image&gt;&gt;(); </code></pre> <p>And I'm adding a collection to the list like this:</p> <pre><code>this._Documents_CompleteClaims.Add(this._Documents_NewClaimList); </code></pre> <p><strike>When I try to loop through the collection, it shows up null. The collection has an object:</p> <p><img src="https://i.stack.imgur.com/rTobA.png" alt=""></p> <p>But the collection count shows 0.</p> <p><img src="https://i.stack.imgur.com/VT5Xw.png" alt=""></p> <p>I used this same method a while back, but with List instead of ObservableCollection. It worked fine before. Any ideas why observable collections aren't working? Or am I just overlooking something silly?</strike></p> <p>So I misdiagnosed the issue. The problem is that the collection in the collection has no items.</p> <p>This is how I was adding the collection to the list of collections:</p> <pre><code>this._Documents_CompleteClaims.Add(this._Documents_NewClaimList); //Add claim to completed list this._Documents_NewClaimList.Clear(); //Clear out the claim list so we can start a new claim </code></pre> <p>I confirmed that the <strong>_Documents_NewClaimList</strong> collection had items. I thought I could add that collection to the collection of collections and then clear the <strong>_Documents_NewClaimList</strong> collection. But if I comment it out the .Clear() line, it works just fine. So I guess I'll need to remove the items in a different way. Maybe I can add the items to a temporary collection, add that temp collection to the collection of collections, and then clear the old collection.</p>
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    1. This table or related slice is empty.
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    1. USernest
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    1. This table or related slice is empty.
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      1. POA list of, list of ObservableCollection<Image> comes up null when looping through it
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    1. COThe code you posted should work. Could you post a small, but complete sample code that demonstrates your issue?
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      1. POA list of, list of ObservableCollection<Image> comes up null when looping through it
      1. USsvick
    2. COyou are looking at the properties of 2 different collections. The first is _Documents_CompleteClaims, the next is the collection it contains. Nowhere do you show adding anything to that collection. You are adding an empty collection to a collection of collections. Nowhere do you show adding an actual image to this._Documents_NewClaimList
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      1. POA list of, list of ObservableCollection<Image> comes up null when looping through it
      1. USBrian Rudolph
    3. CO@BrianRudolph Brian, when I add the collection to the collection, it's not empty. It has items. I don't know why those items aren't staying in the child collection. I'll update my post with how I'm adding them.
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