The page I am working on has a javascript function executed to print parts of the page. For some reason, printing in Safari, causes the window to somehow update. I say somehow, because it does not really refresh as in reload the page, but rather it starts the "rendering" of the page from start, i.e. scroll to top, flash animations start from 0, and so forth. The effect is reproduced by this fiddle: http://jsfiddle.net/fYmnB/ Clicking the print button and finishing or cancelling a print in Safari causes the screen to "go white" for a sec, which in my real website manifests itself as something "like" a reload. While running print button with, let's say, Firefox, just opens and closes the print dialogue without affecting the fiddle page in any way. Is there something with my way of calling the browsers print method that causes this, or how can it be explained - and preferably, avoided? P.S.: On my real site the same occurs with Chrome. In the ex
For an ArrayAdapter, notifyDataSetChanged only works if you use the add, insert, remove, and clear functions on the Adapter.
ReplyDeleteWhen an ArrayAdapter is constructed, it holds the reference for the List that was passed in. If you were to pass in a List that was a member of an Activity, and change that Activity member later, the ArrayAdapter is still holding a reference to the original List. The Adapter does not know you changed the List in the Activity.
Your choices are:
Use the functions of the ArrayAdapter to modify the underlying List (add, insert, remove, clear, etc.)
Re-create the ArrayAdapter with the new List data.
Create your own class derived from BaseAdapter and ListAdapter that allows changing of the underlying List data structure.
Then notifyDataSetChanged will work.
You can use the runOnUiThread method as follows. If you're not using a ListActivity, just adapt the code to get a reference to your ArrayAdapter.
ReplyDeletefinal ArrayAdapter adapter = ((ArrayAdapter)getListAdapter());
runOnUiThread(new Runnable() {
public void run() {
adapter.notifyDataSetChanged();
}
});
I had the same problem and I prefer not to replace the entire ArrayAdapter with a new instance continuously. Thus I have the AdapterHelper do the heavy lifting somewhere else.
ReplyDeleteAdd this where you would normally (try to) call notify
new AdapterHelper().update((ArrayAdapter)adapter, new ArrayList<Object>(yourArrayList));
adapter.notifyDataSetChanged();
AdapterHelper class
public class AdapterHelper {
@SuppressWarnings({ "rawtypes", "unchecked" })
public void update(ArrayAdapter arrayAdapter, ArrayList<Object> listOfObject){
arrayAdapter.clear();
for (Object object : listOfObject){
arrayAdapter.add(object);
}
}
}