hello, Sherman'

how can I help you today?

Hi Mark

I am trying to fill a view with information from a database with information from an asynctask and i am having some trouble

it seems that by the time the asynctask comes back with information the view has already rendered

and when i try to get the information from the variable it always null

"the view has already rendered" is what you want

that's the entire point behind using a background thread, so the main application thread can render the UI

use onPostExecute() of the AsyncTask to update the UI

okay so what do i call in the asynctask to update the ui?

you call Java code

the same sort of code you would use to update the UI anywhere else

is there a specific method that will do that?

there are hundreds of thousands of methods in Android that update the UI, such as setText() on a TextView

i am executing the async task from a DatabaseHelper object

am i supposed to be doing UI updates from an onPostExecute from there?

you need to be doing something to cause the UI to update from there

whether onPostExecute() directly does the UI updates, or delegates to something else, is up to you

if i wanted to refresh a ListView what would I call?

for example, onPostExecute() could trigger an event that causes the activity to know to update the UI, such as via LocalBroadcastManager, or an event bus like Otto

since I have no idea what ListView you are talking about or how it was set up, I cannot answer that

i was looking at your EmPubLite example where you do this through the listener method on the view

it is called setNote

definitely not on the view

okay...

that's a method, defined on the NoteListener interface, implemented on NoteFragment

I pass an instance of the listener to getNoteAsync()

the AsyncTask calls setNote() in onPostExecute()

right.

i was trying to adopt that to what i am trying to do

but i am using a BaseAdapter to combine information from my DB and my View

so?

i don't know how to tell the adapter to update the ui

call notifyDataSetChanged(), which will cause the ListView to re-load all its rows from the adapter

would I call that from setNote()?

(if i was to use your example)

yes

it is telling me that the method doesn't exist

so i am missing something

notifyDataSetChanged() is a method on BaseAdapter, as you can tell by looking at the JavaDocs: http://developer.android.com/reference/android/...

so i would define the BaseAdapter as a class variable and set it before the call and then call notiifyDataSetChanged() on it in the setNote() method?

before the asynctask call I mean

I have no idea what you consider a "class variable" to be, as there is nothing by that term in Java

if you mean "a data member of the object that has the setNote() equivalent", then yes

if you mean "a *static* data member", then no

uhh... what is a variable that all methods in a class can see?

a data member

okay

sorry

for example, setNote() calls setText() on a TextView that is held as a data member of that fragment

and having a BaseAdapter as a data member of that fragment is one way I could do this?

yes

okay thank you for your help

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