Populating a ListView using an ArrayList?
JavaAndroidListviewArraylistJava Problem Overview
My Android
app needs to populate the ListView
using the data from an ArrayList
.
I have trouble doing this. Can someone please help me with the code?
Java Solutions
Solution 1 - Java
You need to do it through an ArrayAdapter
which will adapt your ArrayList (or any other collection) to your items in your layout (ListView, Spinner etc.).
This is what the Android developer guide says:
> A ListAdapter
that manages a ListView
backed by an array of arbitrary objects. By default this class expects that the provided resource id references a single TextView
. If you want to use a more complex layout, use the constructors that also takes a field id. That field id should reference a TextView
in the larger layout resource.
>
> However the TextView
is referenced, it will be filled with the toString()
of each object in the array. You can add lists or arrays of custom objects. Override the toString()
method of your objects to determine what text will be displayed for the item in the list.
>
> To use something other than TextViews
for the array display, for instance ImageViews
, or to have some of data besides toString()
results fill the views, override getView(int, View, ViewGroup)
to return the type of view you want.
So your code should look like:
public class YourActivity extends Activity {
private ListView lv;
public void onCreate(Bundle saveInstanceState) {
setContentView(R.layout.your_layout);
lv = (ListView) findViewById(R.id.your_list_view_id);
// Instanciating an array list (you don't need to do this,
// you already have yours).
List<String> your_array_list = new ArrayList<String>();
your_array_list.add("foo");
your_array_list.add("bar");
// This is the array adapter, it takes the context of the activity as a
// first parameter, the type of list view as a second parameter and your
// array as a third parameter.
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(
this,
android.R.layout.simple_list_item_1,
your_array_list );
lv.setAdapter(arrayAdapter);
}
}
Solution 2 - Java
Also look up ArrayAdapter interface:
ArrayAdapter(Context context, int textViewResourceId, List<T> objects)
Solution 3 - Java
Try the below answer to populate listview using ArrayList
public class ExampleActivity extends Activity
{
ArrayList<String> movies;
public void onCreate(Bundle saveInstanceState)
{
super.onCreate(saveInstanceState);
setContentView(R.layout.list);
// Get the reference of movies
ListView moviesList=(ListView)findViewById(R.id.listview);
movies = new ArrayList<String>();
getMovies();
// Create The Adapter with passing ArrayList as 3rd parameter
ArrayAdapter<String> arrayAdapter =
new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, movies);
// Set The Adapter
moviesList.setAdapter(arrayAdapter);
// register onClickListener to handle click events on each item
moviesList.setOnItemClickListener(new OnItemClickListener()
{
// argument position gives the index of item which is clicked
public void onItemClick(AdapterView<?> arg0, View v,int position, long arg3)
{
String selectedmovie=movies.get(position);
Toast.makeText(getApplicationContext(), "Movie Selected : "+selectedmovie, Toast.LENGTH_LONG).show();
}
});
}
void getmovies()
{
movies.add("X-Men");
movies.add("IRONMAN");
movies.add("SPIDY");
movies.add("NARNIA");
movies.add("LIONKING");
movies.add("AVENGERS");
}
}
Solution 4 - Java
public class Example extends Activity
{
private ListView lv;
ArrayList<String> arrlist=new ArrayList<String>();
//let me assume that you are putting the values in this arraylist
//Now convert your arraylist to array
//You will get an exmaple here
//http://www.java-tips.org/java-se-tips/java.lang/how-to-convert-an-arraylist-into-an-array.html
private String arr[]=convert(arrlist);
@Override
public void onCreate(Bundle bun)
{
super.onCreate(bun);
setContentView(R.layout.main);
lv=(ListView)findViewById(R.id.lv);
lv.setAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1 , arr));
}
}
Solution 5 - Java
Here's an example of how you could implement a list view:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//We have our list view
final ListView dynamic = findViewById(R.id.dynamic);
//Create an array of elements
final ArrayList<String> classes = new ArrayList<>();
classes.add("Data Structures");
classes.add("Assembly Language");
classes.add("Calculus 3");
classes.add("Switching Systems");
classes.add("Analysis Tools");
//Create adapter for ArrayList
final ArrayAdapter<String> adapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1, classes);
//Insert Adapter into List
dynamic.setAdapter(adapter);
//set click functionality for each list item
dynamic.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Log.i("User clicked ", classes.get(position));
}
});
}
Solution 6 - Java
First I created the objects
ListView listview;
ArrayAdapter arrayAdapter;
ArrayList<Albums> listAlbums;
Then on On Create method:
listview = findViewById(R.id.listviewAlbum);
listAlbums = new ArrayList<Albums>();
arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1,
listAlbums);
listview.setAdapter(arrayAdapter);
And then if u are using an API u can use this code to get trough the dataset:
for (Albums albumaux : response.body()) {
listAlbums.add(albumaux);
}
arrayAdapter.notifyDataSetChanged();