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POAndroid: file.getName() error
 

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  1. POAndroid: file.getName() error
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    <p>I'm developing an activity in order to explore the files included in the Tablet, where the user also can select one of them and open it. However when i retrieve the file name it says that there is a NPE. How could I retrieve the file name in order to open it later? Here is my code: File Explorer: </p> <pre><code>public class MainActivity extends ListActivity { private List&lt;String&gt; item = null; private List&lt;String&gt; path = null; private String root; private TextView myPath; static String A; static File file; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); myPath = (TextView)findViewById(R.id.path); root = Environment.getExternalStorageDirectory().getPath(); getDir(root); } private void getDir(String dirPath) { myPath.setText("Location: " + dirPath); item = new ArrayList&lt;String&gt;(); path = new ArrayList&lt;String&gt;(); File f = new File(dirPath); File[] files = f.listFiles(); if(!dirPath.equals(root)) { item.add(root); path.add(root); item.add("../"); path.add(f.getParent()); } for(int i=0; i &lt; files.length; i++) { File file = files[i]; if(!file.isHidden() &amp;&amp; file.canRead()){ path.add(file.getPath()); if(file.isDirectory()){ item.add(file.getName() + "/"); }else{ item.add(file.getName()); } } } ArrayAdapter&lt;String&gt; fileList = new ArrayAdapter&lt;String&gt;(this, R.layout.row, item); setListAdapter(fileList); } @Override protected void onListItemClick(ListView l, View v, int position, long id) { // TODO Auto-generated method stub File file = new File(path.get(position)); if (file.isDirectory()) { if(file.canRead()){ getDir(path.get(position)); }else{ new AlertDialog.Builder(this) .setIcon(R.drawable.ic_launcher) .setTitle("[" + file.getName() + "] folder can't be read!") .setPositiveButton("OK", null).show(); } }else { file.getName(); XMLPullParserActivity.Parsear(this); Intent i = new Intent(MainActivity.this, Correccion.class); startActivity(i); } } public static String getA(){ A = XMLPullParserHandler.getA(); return A; } public static String fileName(){ return file.getName(); } } </code></pre> <p>Open the Selected File in the Activity:</p> <pre><code>public class XMLPullParserActivity { ListView listView; public static void Parsear(Context context){ List&lt;Puntuacion&gt; puntuacion = null; try { XMLPullParserHandler parser = new XMLPullParserHandler(); puntuacion = parser.parse(context.getAssets().open(MainActivity.fileName())); } catch (IOException e) { e.printStackTrace(); } } } </code></pre> <p>LogCat:</p> <pre><code>03-22 09:57:44.296: W/ActivityThread(4943): Application com.example.androidexplorer can be debugged on port 8100... 03-22 09:57:44.398: D/AbsListView(4943): Get MotionRecognitionManager 03-22 09:57:44.507: D/libEGL(4943): loaded /vendor/lib/egl/libEGL_POWERVR_SGX540_120.so 03-22 09:57:44.523: D/libEGL(4943): loaded /vendor/lib/egl/libGLESv1_CM_POWERVR_SGX540_120.so 03-22 09:57:44.523: D/libEGL(4943): loaded /vendor/lib/egl/libGLESv2_POWERVR_SGX540_120.so 03-22 09:57:44.640: D/OpenGLRenderer(4943): Enabling debug mode 0 03-22 09:58:02.656: D/AndroidRuntime(4943): Shutting down VM 03-22 09:58:02.656: W/dalvikvm(4943): threadid=1: thread exiting with uncaught exception (group=0x410a42a0) 03-22 09:58:02.679: E/AndroidRuntime(4943): FATAL EXCEPTION: main 03-22 09:58:02.679: E/AndroidRuntime(4943): java.lang.NullPointerException 03-22 09:58:02.679: E/AndroidRuntime(4943): at com.example.androidexplorer.MainActivity.fileName(MainActivity.java:104) 03-22 09:58:02.679: E/AndroidRuntime(4943): at com.example.androidexplorer.XMLPullParserActivity.Parsear(XMLPullParserActivity.java:25) 03-22 09:58:02.679: E/AndroidRuntime(4943): at com.example.androidexplorer.MainActivity.onListItemClick(MainActivity.java:90) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.app.ListActivity$2.onItemClick(ListActivity.java:319) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.widget.AdapterView.performItemClick(AdapterView.java:298) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.widget.AbsListView.performItemClick(AbsListView.java:1280) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.widget.AbsListView$PerformClick.run(AbsListView.java:3067) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.widget.AbsListView$1.run(AbsListView.java:3968) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.os.Handler.handleCallback(Handler.java:615) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.os.Handler.dispatchMessage(Handler.java:92) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.os.Looper.loop(Looper.java:137) 03-22 09:58:02.679: E/AndroidRuntime(4943): at android.app.ActivityThread.main(ActivityThread.java:4895) 03-22 09:58:02.679: E/AndroidRuntime(4943): at java.lang.reflect.Method.invokeNative(Native Method) 03-22 09:58:02.679: E/AndroidRuntime(4943): at java.lang.reflect.Method.invoke(Method.java:511) 03-22 09:58:02.679: E/AndroidRuntime(4943): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:994) 03-22 09:58:02.679: E/AndroidRuntime(4943): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:761) 03-22 09:58:02.679: E/AndroidRuntime(4943): at dalvik.system.NativeStart.main(Native Method) </code></pre>
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    1. PO
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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    2. PO
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    1. This table or related slice is empty.
    1. COWhere is the NPE? Post the logcat
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      1. POAndroid: file.getName() error
      1. USAleks G
 

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