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POAndroid ListView throwing NullPointerException when I try to scroll
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  1. POAndroid ListView throwing NullPointerException when I try to scroll
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    copied!<p>Not exactly sure what is going on here so I am hoping one of you can point me in the right direction. I have a ListView within a Tab frame and for some reason, it loads but crashes when I try to scroll. </p> <p>Here is all of the information I could gather</p> <p>Here is the Activity that goes into the frame... it parses an XML file into a priority queue, gets the attached intent information, and loads the desired page. </p> <pre><code>public class QScoresFrameActivity extends ListActivity { private PriorityQueue&lt;Score&gt; mScores; private int mDifficulty; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.scoresframe); mDifficulty = getIntent().getIntExtra(getResources().getString(R.string.difficulty), getResources().getInteger(R.integer.normal_level)); mScores = QGameGlobals.ParseScoresXML(this,mDifficulty); setListAdapter(new ScoresAdapter(this)); } private class ScoresAdapter extends BaseAdapter { private LayoutInflater mInflater; public ScoresAdapter(Context context) { mInflater = LayoutInflater.from(context); } public View getView(int position, View convertView, ViewGroup parent) { Score thisScore = mScores.getByIndex(position); convertView = mInflater.inflate(R.layout.scoreview, null); TextView posT; TextView nameT; TextView scoreT; String name = thisScore.getName(); int score = thisScore.getScore(); posT = (TextView)convertView.findViewById(R.id.position); nameT = (TextView)convertView.findViewById(R.id.scorerName); scoreT= (TextView)convertView.findViewById(R.id.scorerScore); posT.setText(String.valueOf(position + 1) + ". "); nameT.setText(name); scoreT.setText(String.valueOf(score)); return convertView; } public int getCount() { return mScores.getLength(); } public Object getItem(int position) { return this; } public long getItemId(int position) { return position; } } </code></pre> <p>}</p> <p>The layout file that holds the list:</p> <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical"&gt; &lt;ListView android:layout_height="wrap_content" android:layout_width="match_parent" android:id="@+android:id/list" /&gt; &lt;/LinearLayout&gt; </code></pre> <p>The layout file for each item in the list:</p> <pre><code> &lt;?xml version="1.0" encoding="utf-8"?&gt; &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/linearLayout1" android:padding="10dp" android:layout_width="fill_parent" android:baselineAligned="false" android:orientation="horizontal" android:layout_height="wrap_content"&gt; &lt;TextView android:layout_height="wrap_content" android:textAppearance="?android:attr/textAppearanceMedium" android:text="TextView" android:paddingRight="10dp" android:id="@+id/position" android:layout_width="50dp" android:textColor="@color/teal" &gt;&lt;/TextView&gt; &lt;TextView android:id="@+id/scorerName" android:layout_height="wrap_content" android:textAppearance="?android:attr/textAppearanceLarge" android:text="TextView" android:layout_width="wrap_content" android:layout_gravity="center_vertical"&gt;&lt;/TextView&gt; &lt;TextView android:id="@+id/scorerScore" android:text="TextView" android:textAppearance="?android:attr/textAppearanceLarge" android:paddingLeft="20dp" android:layout_height="wrap_content" android:gravity="right" android:textColor="@color/gold" android:layout_width="match_parent" android:layout_gravity="center_vertical"/&gt; &lt;/LinearLayout&gt; </code></pre> <p>Priority Queue class....</p> <pre><code>@SuppressWarnings("rawtypes") public class PriorityQueue&lt;T extends Comparable&gt; extends Queue&lt;T&gt; { public PriorityQueue () { super(); } @SuppressWarnings("unchecked") @Override public void enqueue(T item) /* Enqueue a new object of type T into the queue based on its compareTo method. * Sorts from greatest to least. */ { TNode newNode = new TNode(item); if (root == null) { root = newNode; end = newNode; } else { TNode currNode = root; TNode lastNode = root; while (true) { int compVal = item.compareTo(currNode.get()); if (compVal == 1 || compVal == 0) { if (currNode == root) { root = newNode; } else { lastNode.next = newNode; newNode.next = currNode; } newNode.next = currNode; break; } else { if (currNode == end) { currNode.next = newNode; end = newNode; break; } else { lastNode = currNode; currNode = currNode.next; } } } } length++; } } </code></pre> <p>Appreciate the help.</p>
 

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