The document provides a lesson on how to install an application on Android using intents and APK files. It includes sample code snippets for handling the download and installation process, including setting up a user interface with a button to initiate the download. Additionally, it introduces the author, Bruno Delb, highlighting his background in Java mobile application development.

1. Develop on Android
Android Lab Test
www.AndroidLabTest.com
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By Bruno Delb
www.weibo.com/brunodelb
i.youku.com/brunodelb | www.weibo.com/brunodelb | blog.delb.cn
http://i.youku.com/brunoparis
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Officialsite
Lesson : Installation of an application

2. Installation of an application
• In this lesson, you will learn to launch an APK file.
• For this, you will use the Intents.

3. Installation of an application
• To install an application, use the Intent ACTION_VIEW. Specify the
MIME type application/vnd.android.package-archive.
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(path)), "application/vnd.android.package-
archive");
startActivity(intent);

4. Layout main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button
android:id="@+id/btnDownloadAndInstall"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Download &amp; Install" />
</LinearLayout>

5. File Main.java
public class Main extends Activity {
final static String outputPath = Environment.getExternalStorageDirectory() + "/download/";
public void onCreate (Bundle bundle) {
super.onCreate (bundle);
setContentView (R.layout.main);
Button btnDownloadAndInstall = (Button)findViewById (R.id.btnDownloadAndInstall);
btnDownloadAndInstall.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
downloadAPK (
"http://www.mediamobileagency.fr/dl/apps/Media_TextToSpeech.apk",
Environment.getExternalStorageDirectory() + "/download/Media_TextToSpeech.apk"
);
launchAPK (Environment.getExternalStorageDirectory() +
"/download/Media_TextToSpeech.apk");
}
});
}

6. File Main.java
private void downloadAPK (String theUrl, String path) {
try {
URL url = new URL(theUrl);
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("GET");
httpURLConnection.setDoOutput(true);
httpURLConnection.connect();
File file = new File(path);
file.mkdirs();
File outputFile = new File(path);
FileOutputStream fileOutputStream = new FileOutputStream(outputFile);
InputStream inputStream = httpURLConnection.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
while ((len1 = inputStream.read(buffer)) != -1) {
fileOutputStream.write(buffer, 0, len1);
}
fileOutputStream.close();
inputStream.close();
} catch (IOException e) {
}
}

7. Test on your mobile
System_InstallApplication

8. Follow me on my channel PengYooTV …
On my Youku channel
http://i.youku.com/brunoparis
Who am I ?
Bruno Delb (www.delb.cn),
Author of the first french book of development of Java mobile application (2002),
Consultant, project manager and developer of social & mobile applications,
let’s talk about your needs ...
And on Weibo :
http://www.weibo.com/brunodelb