Question

How can I use an ArrayAdapter from another activity? I tried doing the following in MyListActivity.onCreate():

setListAdapter(SomeOtherActivity.myAdapter);

where myAdapter is defined and initialized in SomeOtherActivity. However, I get an empty list, even though I verified that SomeOtherActivity.myAdapter is fully populated via a call to:

SomeOtherActivity.myAdapter.getCount();

If I define and initialize my own adapter in MyListActivity with setListAdapter(myLocalAdapter), it works. Once I switch it to setListAdapter(SomeOtherActivity.myAdapter), I get an empty list. I debugged it and found that the adapter’s getView() isn’t even called.

Help please? Thanks.

In MainActivity.onCreate()

listIsDone = false;
myList = new ArrayList<ItemInfo>();
init = new Runnable() {
  public void run() {
    myList = generate(); // generate the list, takes a while
    Collections.sort(myList, new CustomComparator()); // sorts the list
    myAdapter = new MyInfoAdapter(MainActivity.this, R.layout.row, myList);
    synchronized(this) {
      listIsDone = true;
      notifyAll();
    }
  }
};
Thread thread = new Thread(null, init, "Background");
thread.start;

In my SubActivity.onCreate()

setListAdapter(MainActivity.myAdapter);
doStuff = new Runnable() {
  public void run() {
    synchronized(MainActivity.init) {
      if (!MainActivity.getListDone()) {
        try {
          MainActivity.init.wait(); // wait for list/adapter to be initialized
        } catch (InterruptedException e) {
        }
      }
    }
  }
};
Thread thread = new Thread(null, doStuff, "Background");
thread.start();

I notice I can’t run myAdapter.notifyDataSetChanged() in a Runnable thread(I get a runtime error), but I can do it in a runnable if I run it with runOnUiThread(); I’m guessing all method calls to the adapter needs to be done in the same UI thread?

Answer 1

Please check the accessibility of myAdapter in currentActivity.
It seems you are using the adapter before it get initialized.

@share the code.. for proper solution