Dokon's Story: Android

It is the way creating a custom listview in android.

1. Create Android Project
(1) Click the Start a new Android Studio project.

(2) Click the next button after type Application name and Company Domain.
(Create package name by company domain and application name.)

(3) Click the next button after check Pone and Tablet Check Box.

(4) Click the next button after select Blank Activity.

(5) Click the finish button after type Activity Name, Layout Name, Title, and Menu Resource Name.
(If the finish button is clicked, Android Project is created)

2. Add a ListView in the activity layout, look like below image.

- Activity Layout Source

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

    <ListView android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</RelativeLayout>

3. Create the list item layout.
(1) Click the menu of Layout XML File, look like below image.

(2) Click the finish button after type Layout File Name and Root Tag.

(3) Add a ImageView and a TextView in the list item layout, look like below image.

- List item layout source.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent"
    android:orientation="horizontal">

    <ImageView
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:layout_gravity="center_vertical"
        android:src="@drawable/south_korea"
        android:id="@+id/imageView" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:layout_gravity="center_vertical"
        android:text="Korea"
        android:id="@+id/textView" />
</LinearLayout>

4. Type the code in the activity, look like below image

package com.jmsys.customlistview;

import android.content.Context;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;


public class MainActivity extends ActionBarActivity {

    ListView listview;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listview = (ListView)this.findViewById(R.id.listview);

        // Create ListView Data
        ArrayList<String> list = new ArrayList<String>();
        list.add("Korea");
        list.add("USA");
        list.add("Germany");

        // Custom Adapter Instance
        CustomAdapter adapter = new CustomAdapter(this, list);
        // Set a custom adapter on the ListView
        listview.setAdapter(adapter);

        // Add a Item Click Event on the ListView
        listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                CustomAdapter adapter = (CustomAdapter)listview.getAdapter();
                Toast.makeText(MainActivity.this, adapter.getItem(position).toString(), Toast.LENGTH_LONG).show();
            }
        });
    }

    // Custom Adapter Inner Class
    public class CustomAdapter extends BaseAdapter{
        Context context;
        ArrayList<String> items;
        LayoutInflater inflater;

        public CustomAdapter(Context context, ArrayList<String> items){
            this.context = context;
            this.items = items;
            inflater = LayoutInflater.from(context);
        }

        @Override
        public int getCount() {
            return items.size();
        }

        @Override
        public Object getItem(int position) {
            return items.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View v = convertView;
            if(v == null){
                v = inflater.inflate(R.layout.list_item, null);
            }

            ImageView imageView = (ImageView)v.findViewById(R.id.imageView);
            TextView textView = (TextView)v.findViewById(R.id.textView);

            String nation = items.get(position);
            textView.setText(nation);

            // Set a image of ImageView
            if("Korea".equals(nation)){
                imageView.setImageResource(R.drawable.south_korea);
            }else if("USA".equals(nation)){
                imageView.setImageResource(R.drawable.usa);
            }else if("Germany".equals(nation)){
                imageView.setImageResource(R.drawable.germany);
            }
            return v;
        }
    }
}

※ Refer below video.

It is easy to change the background color of the Action Bar without modify style xml.
You can change the background color by below code.

 // Change the background color into red.
 getSupportActionBar().setBackgroundDrawable(new ColorDrawable(0xFFFF0000));

Example :

[Before to change color]

[After to change color]

[Full Source]

import android.graphics.drawable.ColorDrawable;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
public class ActionBarTestActivity extends ActionBarActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_action_bar_test);
        // Change the background color into red.
        getSupportActionBar().setBackgroundDrawable(new ColorDrawable(0xFFFF0000));
    }
}