creating android adapters listview android studio

When the AdapterView is first created, this argument will be null. The convertView parameter allows a previously created View to be reused.

getView(int position, View convertView, ViewGroup parent): This method creates the View (which may be a single View component like a TextView or a complex set of widgets in a layout) that displays the data for the specified (by position) item/row in the AdapterView.īeyond the position parameter, the getView( ) method gets passed two other important parameters.

Typically, the data set id matches the AdapterView rows so this method just returns the same value.

getItemId(int pos): This method returns the data set’s id for a item/row position of the AdapterView.This method will be used by Android to fetch the appropriate data to build the item/row in the AdapterView. getItem(int pos): get the data item associated with the item (or row) from the AdapterView passed as a parameter to the method.getCount( ): indicates to Android how many items (or rows) are in the data set that will be presented in the AdapterView.These four methods are called by Android to build your AdapterView and to return the correct information when one of the items in the AdapterView is selected. What’s more, the BaseAdapter already provides common implementations for many of the interfaces so you don’t have to override these unless there is a specific need.Īt a minimum, you will need to implement four methods. Rather than creating a class the implements Adapter, SpinnerAdapter or ListAdapter, just extend BaseAdapter and implement the specialized methods for either a ListView or Spinner. BaseAdapter is provided as a convenience to Android developers.

Import 7.app.Adapter interface defines 10 methods that must be implemented by the developer. Step 3 − Add the following code to src/MainActivity.java import android.os.Bundle Step 2 − Add the following code to res/layout/activity_main.xml.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project. This example demonstrates how do I add custom adapter for my listView in android.

Creating android adapters listview android studio