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POHow to access (iterate?) an ArrayList/Hashmap in another class?
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  1. POHow to access (iterate?) an ArrayList/Hashmap in another class?
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    copied!<p>I have defined an ArrayList in my main class where I am loading data from an XML feed and creating various tabs with different activities:</p> <pre><code>static ArrayList&lt;HashMap&lt;String, String&gt;&gt; mylist = new ArrayList&lt;HashMap&lt;String, String&gt;&gt;(); </code></pre> <p>Example of where I put a map entry into the ArrayList of HashMaps:</p> <pre><code>for (int i = 0; i &lt; 10; i++) { HashMap&lt;String, String&gt; map = new HashMap&lt;String, String&gt;(); Element e = (Element)nodes.item(i); map.put("id", XMLfunctions.getValue(e, "id")); map.put("lat", "Lat: " + XMLfunctions.getValue(e, "lat")); map.put("long", "Long: " + XMLfunctions.getValue(e, "long")); mylist.add(map); } </code></pre> <p>The first tab is a ListViewActivity and I am successfully able to create the list by referencing the ArrayList in the main class: <em>class.mylist</em> via a List Adapter:</p> <pre><code>ListAdapter adapter = new SimpleAdapter( ListViewActivity.this, main.mylist, R.layout.list, new String[] { "id", "lat", "long" }, new int[] { R.id.item_id, R.id.item_lat, R.id.item_long }); setListAdapter(adapter); </code></pre> <p>My second tab is a MapView and I am able to successfully switch tabs, display the map within the tab layout and pan &amp; zoom etc.</p> <p>Where I need help is with understanding how to access the 'lat' and 'long' strings within the "mylist" ArrayList/Hashmap in the main class (<strong>Note</strong>: <em>I declared the ArrayList/Hashmap in the main class and then share it across all the activities because it is quite a large XML feed and I did not want to be reloading data or having too many objects in memory</em>).</p> <p>My objective is to then convert these lat/long co-ordinates into GeoPoints and display them using a Map Overlay; I am already able to do this using fixed GeoPoints hard-coded into my Map activity class. However, as I wrote above, I now need to replace these 'fixed' GeoPoints and instead use the contents of the "mylist" ArrayList/Hashmap.</p> <p>I am new (&lt;1 month experience) to programming Java/Android, so I hope this all makes sense? And I hope that someone will be able to explain / give an example of how I can access the data... I've tried implementing various measures such as '<strong>Iterations</strong>', but it's not working yet.</p>
 

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