ListView CustomArrayAdapter ViewHolder
Using Android Studio 1.4
Application Name: MyCustomArrayAdapter1
Follow the wizard to create New Blank Activity.
2) Edit MainActivity.java
package com.notarazi.mylistactivity1; import android.app.ListActivity; import android.os.Bundle; import android.widget.ArrayAdapter; public class MainActivity extends ListActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); super.onCreate(savedInstanceState); String[] values = new String[]{"Android", "iPhone", "WindowsMobile", "Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X", "Linux", "OS/2"}; ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, values); setListAdapter(adapter); } } |
OUTCOME.
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" xmlns:app="http://schemas.android.com/apk/res-auto" 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" app:layout_behavior="@string/appbar_scrolling_view_behavior" tools:showIn="@layout/activity_main" tools:context=".MainActivity"> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="#FFFFFF"> <ListView android:id="@+id/listView1" android:layout_width="fill_parent" android:layout_height="fill_parent" /> </LinearLayout> </RelativeLayout> |
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:id="@+id/txtHeader" android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center_vertical" android:layout_alignParentTop="true" android:layout_alignParentBottom="true" android:textStyle="bold" android:textSize="22dp" android:textColor="#FFFFFF" android:padding="10dp" android:text="Weather Photos" android:background="#336699" /> </LinearLayout> |
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding="10dp"> <ImageView android:id="@+id/imgIcon" android:layout_width="wrap_content" android:layout_height="fill_parent" android:gravity="center_vertical" android:layout_alignParentTop="true" android:layout_alignParentBottom="true" android:layout_marginRight="15dp" android:layout_marginTop="5dp" android:layout_marginBottom="5dp" /> <TextView android:id="@+id/txtTitle" android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center_vertical" android:layout_alignParentTop="true" android:layout_alignParentBottom="true" android:textStyle="bold" android:textSize="22dp" android:textColor="#000000" android:layout_marginTop="5dp" android:layout_marginBottom="5dp" /> </LinearLayout> |
package com.notarazi.mycustomarrayadapter1; public class Weather { public int icon; public String title; public Weather(){ super(); } public Weather(int icon, String title) { super(); this.icon = icon; this.title = title; } } |
package com.notarazi.mycustomarrayadapter1; import android.app.Activity; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.widget.ImageView; import android.widget.TextView; public class WeatherAdapter extends ArrayAdapter<Weather> { Context context; int layoutResourceId; Weather data[] = null; public WeatherAdapter(Context context, int layoutResourceId, Weather[] data) { super(context, layoutResourceId, data); this.layoutResourceId = layoutResourceId; this.context = context; this.data = data; } @Override public View getView(int position, View convertView, ViewGroup parent) { View row = convertView; WeatherHolder holder = null; if(row == null) { LayoutInflater inflater = ((Activity)context).getLayoutInflater(); row = inflater.inflate(layoutResourceId, parent, false); holder = new WeatherHolder(); holder.imgIcon = (ImageView)row.findViewById(R.id.imgIcon); holder.txtTitle = (TextView)row.findViewById(R.id.txtTitle); row.setTag(holder); } else { holder = (WeatherHolder)row.getTag(); } Weather weather = data[position]; holder.txtTitle.setText(weather.title); holder.imgIcon.setImageResource(weather.icon); return row; } static class WeatherHolder { ImageView imgIcon; TextView txtTitle; } } |
What is the use of ViewHolder?
Download the icons and add them to drawable images
MyCustomArrayAdapter1-drawable.zip
package com.notarazi.mycustomarrayadapter1; import android.os.Bundle; import android.support.design.widget.FloatingActionButton; import android.support.design.widget.Snackbar; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.Toolbar; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.ListView; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(toolbar); setCustomListView(); FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); fab.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG) .setAction("Action", null).show(); } }); } private void setCustomListView() { Weather weather_data[] = new Weather[] { new Weather(R.drawable.cloudy_48, "Cloudy"), new Weather(R.drawable.showers_48, "Showers"), new Weather(R.drawable.snow_48, "Snow"), new Weather(R.drawable.storm_48, "Storm"), new Weather(R.drawable.sunny_48, "Sunny") }; WeatherAdapter adapter = new WeatherAdapter(this, R.layout.listview_item_row, weather_data); ListView listView1 = (ListView)findViewById(R.id.listView1); View header = (View)getLayoutInflater().inflate(R.layout.listview_header_row, null); listView1.addHeaderView(header); listView1.setAdapter(adapter); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.menu_main, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); //noinspection SimplifiableIfStatement if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); } } |
OUTCOME.
http://www.ezzylearning.com/tutorial/customizing-android-listview-items-with-custom-arrayadapter