Android - get children inside a View?

for(int index = 0; index < ((ViewGroup) viewGroup).getChildCount(); index++) {
    View nextChild = ((ViewGroup) viewGroup).getChildAt(index);
}

Will that do?

If you not only want to get all direct children but all children's children and so on, you have to do it recursively:

private ArrayList<View> getAllChildren(View v) {

    if (!(v instanceof ViewGroup)) {
        ArrayList<View> viewArrayList = new ArrayList<View>();
        viewArrayList.add(v);
        return viewArrayList;
    }

    ArrayList<View> result = new ArrayList<View>();

    ViewGroup vg = (ViewGroup) v;
    for (int i = 0; i < vg.getChildCount(); i++) {

        View child = vg.getChildAt(i);

        ArrayList<View> viewArrayList = new ArrayList<View>();
        viewArrayList.add(v);
        viewArrayList.addAll(getAllChildren(child));

        result.addAll(viewArrayList);
    }
    return result;
}

To use the result you could do something like this:

    // check if a child is set to a specific String
    View myTopView;
    String toSearchFor = "Search me";
    boolean found = false;
    ArrayList<View> allViewsWithinMyTopView = getAllChildren(myTopView);
    for (View child : allViewsWithinMyTopView) {
        if (child instanceof TextView) {
            TextView childTextView = (TextView) child;
            if (TextUtils.equals(childTextView.getText().toString(), toSearchFor)) {
                found = true;
            }
        }
    }
    if (!found) {
        fail("Text '" + toSearchFor + "' not found within TopView");
    }

You can always access child views via View.findViewById() http://developer.android.com/reference/android/view/View.html#findViewById(int).

For example, within an activity / view:

...
private void init() {
  View child1 = findViewById(R.id.child1);
}
...

or if you have a reference to a view:

...
private void init(View root) {
  View child2 = root.findViewById(R.id.child2);
}