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POUse on "Adapter" for two (or more) parent views?
 

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    <p>Is it possible to use one adapter class (and it's instance) (e.g. own sub-class of <code>ArrayAdapter&lt;ownDataType&gt;</code> for two (or more) different views?</p> <p>In my <code>Activity</code>, I have two <code>Spinner</code> objects that are used to show (and select) related data: A list of parent categories and a list of sub-categories of the selected parent category. Of course, the list in the sub-category-<code>Spinner</code> is updated (setting a new <code>ArrayAdapter</code>), when the parent category is changed. However, I also want to be able to set a sub-category directly (and choose the parent category automatically) when the Activity is created. This makes things complicated.</p> <p>My idea for a simple and clean solution now is to create ONE own Adapter-Class (e.g. derived from <code>ArrayAdapter&lt;CategoryPair&gt;</code>, where <code>CategoryPair</code> is a simple class that holds a pair of parent- and sub-category) and this own adapter class handles all the logic to keep data consistent (much simpler there).</p> <p>In the <code>getView(int position, View convertView, ViewGroup parent)</code> method of the <code>Adapter</code>-class I need to recognize reliably for which of the two <code>Spinner</code> objects in my activity I need to create a view. </p> <p>Can I rely on the <code>parent</code> parameter?</p> <p>Do you think my idea is a good one?</p> <p><em>Edit:</em> Code example:</p> <p>My adapter class:</p> <pre><code>public class CategoryPair { Category parent; Category sub; } public class CategoriesAdapter extends ArrayAdapter&lt;CategoryPair&gt; { private Spinner parentSpinner; private Spinner subSpinner; public CategoriesAdapter(Context context, int textViewResourceId, Spinner par, Spinner sub) { super(context, textViewResourceId); parentSpinner = par; subSpinner = sub; } @Override public View getView(int position, View convertView, ViewGroup parent) { if (parent == parentSpinner) { // } else if (parent == subSpinner) { // } else { Log.e(TAG, "Invalid parent in CategoriesAdapter"); } return super.getView(position, convertView, parent); } </code></pre>
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