Question

I am trying to read lines stored in a separate text file into my android application and have each line show up in the list view.

The problem is that I cannot get anything to appear despite the fact my code says their are not errors in it. As you read this code, I will clarify that my ListView is named “addresslist” and the file i’m reading from is named “myaddress.txt”. I appreciate any help.

ListView listView= (ListView) findViewById(R.id.addresslist); 
try{
    InputStream instream = openFileInput("myaddress.txt");

    InputStreamReader inputreader = new InputStreamReader(instream);
    BufferedReader buffreader = new BufferedReader(inputreader);


    ArrayList<String> lines = new ArrayList<String>();
    boolean hasNextLine =true;
    while (hasNextLine){
        String line =  buffreader.readLine();
        lines.add(line);
        hasNextLine = line != null;
    }

    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,R.id.addresslist,lines);

    listView.setAdapter(adapter);

    instream.close();

    }
    catch(java.io.FileNotFoundException e){

    }catch(java.io.IOException e){

    }

}

With the following errors in the log:

12-08 01:21:30.394: E/Trace(1500): [ 12-08 01:21:30.864  1500: 1500 V/Home to School 4828 N. Crescent Norridge IL 60706, 5500 N St Louis Avenue Chicago IL 60625; Home to School 4828 N. Crescent Norridge IL 60706, 5500 N St Louis Avenue Chicago IL 60625; 
12-08 01:21:30.864: D/AndroidRuntime(1500): Shutting down VM
12-08 01:21:30.924: W/dalvikvm(1500): threadid=1: thread exiting with uncaught exception (group=0xb3e92288)
12-08 01:21:30.944: E/AndroidRuntime(1500): FATAL EXCEPTION: main
12-08 01:21:30.944: E/AndroidRuntime(1500): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tripapp/com.tripapp.Frontpage}: java.lang.NullPointerException: println needs a message
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.ActivityThread.access$600(ActivityThread.java:130)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.os.Handler.dispatchMessage(Handler.java:99)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.os.Looper.loop(Looper.java:137)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.ActivityThread.main(ActivityThread.java:4745)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at java.lang.reflect.Method.invokeNative(Native Method)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at java.lang.reflect.Method.invoke(Method.java:511)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at dalvik.system.NativeStart.main(Native Method)
12-08 01:21:30.944: E/AndroidRuntime(1500): Caused by: java.lang.NullPointerException: println needs a message
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.util.Log.println_native(Native Method)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.util.Log.v(Log.java:117)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at com.tripapp.Frontpage.onCreate(Frontpage.java:61)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.Activity.performCreate(Activity.java:5008)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
12-08 01:21:30.944: E/AndroidRuntime(1500):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
12-08 01:21:30.944: E/AndroidRuntime(1500):     ... 11 more

Answer 1

First move your file in assets folder in your project and use this code for reading file from assets folder :

    try{
    InputStream inputreader = getAssets().open("myaddress.txt");
    BufferedReader buffreader = new BufferedReader(new InputStreamReader(inputreader));

   // your code here