Creating and testing the Android App

Using isCOBOL IDE

1.	Right click on simple_COBOL_HTML in the Explorer tree

2.	Choose Export

3.	Choose Project as Android Application from the isCOBOL tree

4.	Select the desired project from the list, then click Next

5.	Provide the required information: Android SDK location, target version, package and the folder where the generated apk should be saved. Example:

Note - Do not use the same package for more applications. The package is a sort of unique ID in the Android system.

 

The "Enable WebView Remote Debugging" option enables the ability to attach the app with a Chrome browser in order to debug the HTML/JS frontend as described here.

 

6.	You can click finish or go ahead with the following optional steps.

7.	The next step allows to customize permissions. By default, only WRITE_EXTERNAL_STORAGE is active.

8.	The next step allows you to configure the application icon

9.	The next step allows you to exclude some of the project items (e.g. a program or a css file). Ensure that these items are really useless before excluding them, otherwise your app may not work correctly.

10.	If you have a valid keystore to provide or you wish to exclude some project files from the app, click Next, otherwise click Finish.

Note - If no keystore is provided, the IDE will include a default one. The default keystore is suitable for testing purposes. Before publishing your app in the Marketplace, you should apply a valid keystore to it.

Onc e the apk has been generated, you can test it either in the AVD (Android Virtual Device, the emulator installed along with the SDK) or in a real physical Android device.

In order to test it in a real device, copy the apk to the device through USB or network file transfer features and install it.

In order to test it in the AVD, run the following command:

adb install path/to/Simple.apk

Note - the above command must be adjusted according to the location and name of your apk.

The above command installs the app in the emulator and starts it. Find your app in the emulator screen and touch it to start it:

 

Without isCOBOL IDE

1.	Create an empty folder to host project files (e.g. “C:\android_test”)

2.	Run the command:

android create project --target 1 --name simple_ANDROID --path c:\android_test --activity MainActivity --package com.example.simple_android

You should obtain the following output

Created directory C:\android_test\src\com\example\simple_android Added file c:\android_test\src\com\example\simple_android\MainActivity.java Created directory C:\android_test\res Created directory C:\android_test\bin Created directory C:\android_test\libs Created directory C:\android_test\res\values Added file c:\android_test\res\values\strings.xml Created directory C:\android_test\res\layout Added file c:\android_test\res\layout\main.xml Created directory C:\android_test\res\drawable-xhdpi Created directory C:\android_test\res\drawable-hdpi Created directory C:\android_test\res\drawable-mdpi Created directory C:\android_test\res\drawable-ldpi Added file c:\android_test\AndroidManifest.xml Added file c:\android_test\build.xml Added file c:\android_test\proguard-project.txt

3.	In the directory you created at step 1, edit the file AndoirdManifest.xml and replace the current content with the following:

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android"     package="com.example.simple_android"     android:versionCode="1"     android:versionName="1.0"     android:installLocation="auto" >     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />       <uses-sdk         android:minSdkVersion="8"         android:targetSdkVersion="17" />       <application         android:allowBackup="true"         android:icon="@drawable/ic_launcher"         android:label="@string/app_name" >         <activity             android:name="com.example.simple_android.MainActivity"             android:label="@string/app_name"             android:configChanges="keyboardHidden|orientation|screenSize" >             <intent-filter>                 <action android:name="android.intent.action.MAIN" />                 <category android:name="android.intent.category.LAUNCHER" />             </intent-filter>         </activity>     </application> </manifest>

The manifest file describes the fundamental characteristics of the app and defines each of its components.

Our main goal is to obtain write permissions on the device in order to store the html files for the UI and let the COBOL program create files if necessary.

4.	Switch to the res\layout sub folder, rename the file main.xml to activity_main.xml and replace the current content with the Content of main_activity.xml

5.	Switch to the src\com\example\simple_android sub folder and edit the file MainActivity.java replacing the current content with the Content of MainActivity.java.

6.	Add ismobile.jar (taken from C:\Program Files\Veryant\isCOBOL2017R1\mobile\lib) and cobol.jar (previously produced) to the libs sub folder.

7.	Create a folder named “raw” under the res\layout sub folder and put html.zip (previously created) into that folder.

8.	(optional) Edit the file strings.xml under the res\values subfolder and provide a custom name for your app. The current name is “MainActivity”, you might call it “simple_ANDROID” to make it match with the project name or you can use whatever name you prefer.

9.	From the root directory of your project (e.g. C:\android_test) run the command:

ant debug

The above command builds the apk file of your app

10.	If you haven’t done yet, create and configure an emulator as epxlained at The AVD Manager .

11.	Start the emulator.

12.	From the root directory of your project (e.g. C:\android_test) run the command:

adb install bin/simple_ANDROID-debug.apk

The above command installs the app in the emulator and starts it. Find your app in the emulator screen and touch it to start it:

Note - for better performance and a more accurate result, you can copy the apk on a real physical Android device and test it there.

Content of main_activity.xml

<WebView  xmlns:android="http://schemas.android.com/apk/res/android"     android:id="@+id/webView1"     android:layout_width="fill_parent"     android:layout_height="fill_parent" />

The WebView control allows to render the HTML user interface of our application. This is the only control we need.

Content of MainActivity.java

package com.example.simple_android;   import java.io.PrintWriter; import java.io.StringWriter;   import javax.crypto.Cipher; import javax.crypto.spec.SecretKeySpec;   import android.os.Bundle; import android.webkit.WebView;   import com.iscobol.iscobol4android.IsCobolMainActivity;   public class MainActivity extends IsCobolMainActivity {      @Override    protected void onCreate(Bundle savedInstanceState) {       super.onCreate(savedInstanceState);       setContentView(R.layout.activity_main);         final WebView webView = (WebView) findViewById(R.id.webView1);       init (webView, R.raw.html);    } }