View video tutorial

ANDROID Simple Adapter

ANDROID

Android Simple Adapter is a type of adapter that is used as a bridge between data and view.

Android Simple Adapter with ListView


➔ The Android SimpleAdapter is used as a bridge between static data from an ArrayList of Map objects and views defined in an XML layout file.

➔ The SimpleAdapter displays the map data of the ArrayList in a predefined XML view.

Syntax: SimpleAdatper constructor
SimpleAdapter(Context context, List<? extends Map<String, ?>> data, int resource, String[] from, int[] to) 

Simple Adapter with ListView implementation

➔ Spinner in XML activity_main.xml file
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <ListView
        android:id="@+id/listview"
        android:layout_width="401dp"
        android:layout_height="486dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.314" />
</androidx.constraintlayout.widget.ConstraintLayout>

➔ Layout design for list items layout/items_layout.xml file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:orientation="horizontal"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="13dp"
        android:layout_height="87dp"
        android:layout_weight="1"
        tools:srcCompat="@tools:sample/avatars" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="87dp"
        android:layout_weight="1"
        android:text="TextView" />
</LinearLayout>

➔ Set simpleadapter object to the listview

Create an SimpleAdapter using the arraylist, layout file, and static arrays and set it to the listview in the MainActivity.java file.

package com.example.myapplication;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

import java.util.ArrayList;
import java.util.HashMap;

public class MainActivity extends AppCompatActivity {
    ListView listView;
    String names[] = { "Cat", "Cat",  "Dog"};
    int imageIds[] = { R.drawable.animals_cat, R.drawable.animals_cat2, R.drawable.animals_dog};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        EdgeToEdge.enable(this);
        setContentView(R.layout.activity_main);
        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main), (v, insets) -> {
            Insets systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars());
            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom);
            return insets;
        });
        listView = (ListView) findViewById(R.id.listview);

        ArrayList<HashMap<String, Object>> list = new ArrayList<>();

        for (int i = 0; i < names.length; i++) {
            HashMap<String, Object> map = new HashMap<>();
            map.put("name", names[i]);
            map.put("image", imageIds[i]);
            list.add(map);
        }
        String[] from = { "image", "name"};
        int to[] = { R.id.imageView, R.id.textView };
        SimpleAdapter simpleAdapter = new SimpleAdapter(
                getApplicationContext(), list,
                R.layout.items_layout, from, to);

        // set the simpleAdapter to the ListView
        listView.setAdapter(simpleAdapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                HashMap<String,Object> map = (HashMap<String, Object>) parent.getItemAtPosition(position);
                Toast.makeText(getApplicationContext(), map.get("name").toString(), Toast.LENGTH_SHORT).show();
            }
        });
    }
}

➔ Output
android-spinner

android-spinner