Convert ArrayList to String array in Android

Question

I have a ArrayList that contains values in the form [ann,john]. I want to convert this ArrayList into a String array in the form {"ann","john"}.

How should I do this?

My Android code:

     final Button markabsent = (Button) findViewById(R.id.Button02);       markabsent.setOnClickListener(new View.OnClickListener() {           public void onClick(View v) {              // Perform action on click              Toast.makeText(display.this,"You have marked the students absent",Toast.LENGTH_SHORT).show();               SparseBooleanArray checkedabsent = lView.getCheckedItemPositions();                for (int i = 0; i < arr2.length; i++)              {                 if (checkedabsent.get(i))                  {                     items2.add(arr2[i]);                     System.out.println(items2);                  }             }              Log.d("", "items:");             for (String string : items2)             {                 Log.d("string is", string);               }             }       });   

My Logcat:

     11-10 21:44:00.414: INFO/System.out(2316): [ann, john, ann]      11-10 21:44:00.414: DEBUG/(2316): items:      11-10 21:44:00.414: DEBUG/string is(2316): ann      11-10 21:44:00.414: DEBUG/string is(2316): john 

I tried doing everything mentioned in the answers but my logcat just doesn't seem to imrove

Here is the one giving exceptions:

          11-10 22:14:20.855: INFO/System.out(3322): [Ljava.lang.String;@44eb6ff0           11-10 22:16:38.186: ERROR/AndroidRuntime(3411): FATAL EXCEPTION: main           11-10 22:16:38.186: ERROR/AndroidRuntime(3411): java.lang.ClassCastException: [Ljava.lang.Object;           11-10 22:16:38.186: ERROR/AndroidRuntime(3411):     at com.example.display$2.onClick(display.java:124)           11-10 22:16:38.186: ERROR/AndroidRuntime(3411):     at android.view.View.performClick(View.java:2408)           11-10 22:16:38.186: ERROR/AndroidRuntime(3411):     at android.view.View$PerformClick.run(View.java:8816)           11-10 22:16:38.186: ERROR/AndroidRuntime(3411):     at android.os.Handler.handleCallback(Handler.java:587) 

Here is one more:

          11-10 22:14:20.875: DEBUG/string is(3322): ann           11-10 22:14:20.875: INFO/System.out(3322): [Ljava.lang.String;@44eb7720           11-10 22:14:20.875: INFO/System.out(3322): [Ljava.lang.String;@44eb7720           11-10 22:14:20.885: INFO/System.out(3322): [Ljava.lang.String;@44eb7720           11-10 22:14:20.895: DEBUG/string is(3322): john           11-10 22:14:20.895: INFO/System.out(3322): [Ljava.lang.String;@44eb7de8           11-10 22:16:38.186: ERROR/AndroidRuntime(3411):     at com.example.display$2.onClick(display.java:124) 

Answer 1

Use the method "toArray()"

ArrayList<String>  mStringList= new ArrayList<String>(); mStringList.add("ann"); mStringList.add("john"); Object[] mStringArray = mStringList.toArray();  for(int i = 0; i < mStringArray.length ; i++){     Log.d("string is",(String)mStringArray[i]); } 

or you can do it like this: (mentioned in other answers)

ArrayList<String>  mStringList= new ArrayList<String>(); mStringList.add("ann"); mStringList.add("john"); String[] mStringArray = new String[mStringList.size()]; mStringArray = mStringList.toArray(mStringArray);  for(int i = 0; i < mStringArray.length ; i++){     Log.d("string is",(String)mStringArray[i]); } 

http://developer.android.com/reference/java/util/ArrayList.html#toArray()