Load WebP from Internet and display in ListView
WebP is a modern image format that provides superior lossless and lossy compression for images on the web. Details refer Google Developers - WebP.
Related
To use CustomTabsIntent.Builder in our app, To use CustomTabsIntent.Builder, edit app/build.gradle to add dependencies of compile 'com.android.support:customtabs:23.0.0'.
The WebP images load from the page Google Developers - WebP Image Galleries.
MainActivity.java
package com.blogspot.android_er.androidimage;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.customtabs.CustomTabsIntent;
import android.support.v7.app.AppCompatActivity;
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.io.IOException;
import java.io.InputStream;
import java.lang.ref.WeakReference;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.Arrays;
public class MainActivity extends AppCompatActivity {
final static String src[] = {
"https://www.gstatic.com/webp/gallery3/1_webp_ll.webp",
"https://www.gstatic.com/webp/gallery3/1_webp_a.webp",
"https://www.gstatic.com/webp/gallery3/2_webp_ll.webp",
"https://www.gstatic.com/webp/gallery3/2_webp_a.webp",
"https://www.gstatic.com/webp/gallery3/3_webp_ll.webp",
"https://www.gstatic.com/webp/gallery3/3_webp_a.webp",
"https://www.gstatic.com/webp/gallery3/4_webp_ll.webp",
"https://www.gstatic.com/webp/gallery3/4_webp_a.webp",
"https://www.gstatic.com/webp/gallery3/5_webp_ll.webp",
"https://www.gstatic.com/webp/gallery3/5_webp_a.webp" };
ListView imageList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageList = (ListView) findViewById(R.id.imagelist);
ArrayList<String> srcList = new ArrayList<String>(Arrays.asList(src));
imageList.setAdapter(new CustomListAdapter(this, srcList));
imageList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String imageSrc = src[position];
Toast.makeText(MainActivity.this,
imageSrc,
Toast.LENGTH_LONG).show();
Uri imageUri = Uri.parse(imageSrc);
new CustomTabsIntent.Builder()
.build()
.launchUrl(MainActivity.this, imageUri);
}
});
}
// ----------------------------------------------------
public class CustomListAdapter extends BaseAdapter {
private ArrayList<String> listData;
private LayoutInflater layoutInflater;
public CustomListAdapter(Context context, ArrayList<String> listData) {
this.listData = listData;
layoutInflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
return listData.size();
}
@Override
public Object getItem(int position) {
return listData.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.row, null);
holder = new ViewHolder();
holder.icon = (ImageView)convertView.findViewById(R.id.icon);
holder.text = (TextView)convertView.findViewById(R.id.text);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.text.setText(
String.valueOf(position) + "\n" + src[position]);
if (holder.icon != null) {
new BitmapWorkerTask(holder.icon).execute(listData.get(position));
}
return convertView;
}
class ViewHolder {
ImageView icon;
TextView text;
}
}
// ----------------------------------------------------
// Load bitmap in AsyncTask
// ref:
// http://developer.android.com/training/displaying-bitmaps/process-bitmap.html
class BitmapWorkerTask extends AsyncTask<String, Void, Bitmap> {
private final WeakReference<ImageView> imageViewReference;
private String imageUrl;
public BitmapWorkerTask(ImageView imageView) {
// Use a WeakReference to ensure the ImageView can be garbage
// collected
imageViewReference = new WeakReference<ImageView>(imageView);
}
// Decode image in background.
@Override
protected Bitmap doInBackground(String... params) {
imageUrl = params[0];
return LoadImage(imageUrl);
}
// Once complete, see if ImageView is still around and set bitmap.
@Override
protected void onPostExecute(Bitmap bitmap) {
if (imageViewReference != null && bitmap != null) {
final ImageView imageView = imageViewReference.get();
if (imageView != null) {
imageView.setImageBitmap(bitmap);
}
}
}
private Bitmap LoadImage(String URL) {
Bitmap bitmap = null;
InputStream in = null;
try {
in = OpenHttpConnection(URL);
bitmap = BitmapFactory.decodeStream(in);
in.close();
} catch (IOException e1) {
}
return bitmap;
}
private InputStream OpenHttpConnection(String strURL)
throws IOException {
InputStream inputStream = null;
URL url = new URL(strURL);
URLConnection conn = url.openConnection();
try {
HttpURLConnection httpConn = (HttpURLConnection) conn;
httpConn.setRequestMethod("GET");
httpConn.connect();
if (httpConn.getResponseCode() == HttpURLConnection.HTTP_OK) {
inputStream = httpConn.getInputStream();
}
} catch (Exception ex) {
}
return inputStream;
}
}
}
layout/row.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="@+id/icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
layout/activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:padding="16dp"
android:orientation="vertical"
tools:context="com.blogspot.android_er.androidimage.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:autoLink="web"
android:text="http://android-er.blogspot.com/"
android:textStyle="bold" />
<ListView
android:id="@+id/imagelist"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</LinearLayout>
uses-permission of "android.permission.INTERNET" is needed in AndroidManifest.xml
