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I was trying to convert List<String> to String[] allAim= new String[25]; i.e. into allAim string array,
code snippet is: 

List<String> myString = new ArrayList<String>();
myString=db.getAllAlarmAim();
Object[] mStringArray = myString.toArray();
for(int i = 0; i < mStringArray.length ; i++) {
    Log.d("string is",(String)mStringArray[i]);
    allAim[i]=(String)mStringArray[i].toString(); 
}

but when I try to access allAim, the app crashes

Blackbelt
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Anuj
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  • possible duplicate of [Convert list to array in Java](http://stackoverflow.com/questions/9572795/convert-list-to-array-in-java) – VGR Jul 15 '15 at 20:41

1 Answers1

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Based on your code, you can convert List<String> myString to String[] mStringArray as follows:

 Object[] mStringArray = myString.toArray(new String[myString.size()]);

your code will be:

    List<String> myString = new ArrayList<String>();
    myString=db.getAllAlarmAim();
   Object[] mStringArray= myString.toArray(new String[myString.size()]);

    for(int i = 0; i < mStringArray.length ; i++){
        Log.d("string is", (String)mStringArray[i]);
    }
bmargulies
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Jorgesys
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    you don't need both. either `myString.toArray(mStringArray);` or `mStringArray= myString.toArray(new String[0]);` is sufficient – njzk2 Jul 15 '15 at 18:28
  • I know, just to be according with their code, i have updated my answer, thank you. – Jorgesys Jul 15 '15 at 20:20
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    First two lines can be collapsed into `List myString = db.getAllAlarmAim();` – f_puras Jul 15 '15 at 20:27
  • 'for(int i = 0; i < mStringArray.length ; i++){ Log.d("string is", (String)mStringArray[i]); allAlarmAim[i]= (String)mStringArray[i]; } aa=new ArrayAdapter(this,android.R.layout.simple_list_item_1,allAlarmAim); l1.setAdapter(aa);' HERE allAlarmAim does not get any values,WHY??? – Anuj Jul 17 '15 at 03:19
  • in the code snippet i have mentioned about array allAim, WHY CANT I USE THIS ARRAY OUTSIDE LOOP TO populate list – Anuj Jul 17 '15 at 03:35