I want to add a item to the child Today from another activity to the ExpandableListView. The activity where I want to add it is named LocHistory, here is a the code to add something to the list:

Code:
	static void addListData(final Context context) {
		List<NewsItem> list = listDataChild.get("Today");
		NewsItem newsData = new NewsItem();
		newsData = new NewsItem();
		newsData.setHeadline("11.11111, 1.1111");
		newsData.setSpeed("1.11KM/H");
		newsData.setDirection("111");
		newsData.setDate("11-1-1111 11:11:11");
		list.add(0, newsData);
		listDataChild.put("Today", list);
	}
This is working when I have call the function in the same class (LocHistory). But when I call it in MainActivity like this:

Code:
    public class MainActivity extends Activity {
    	
    	Button button2;
    	
    	@Override
    	public void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    		
    		button2 = (Button) this.findViewById(R.id.button2);
    
    		button2.setOnClickListener(new OnClickListener() {
    			public void onClick(View v) {
    				LocHistory.addListData(getBaseContext());
    			}
    		});
    	}
    }
Then there is nothing added to the list. Is it possible to add a item from another activity to ExpandableListView? I want if there's something added that the class LocHistory is not going to open, so I think startActivity with a intent is not a option here (but i'm not sure).

(The java sources can be found here:
MainActivity.java
LocHistory.java
NewsItem.java
ExpandableListAdapter.java)