coffeeplanter / Minimum

Minimal Android project written in a simple text editor, without IDE.

Minimum

This branch contains the application with layout resource.
See the minimally possible application and MVP app in the appropriate git branches.

This repo contains three Android applications:

• minimally possible app (minimal-app branch);
• app with layout resource (this branch — master);
• simple app using MVP (Model — View — Presenter) architecture (mvp-app branch).

This is minimal Android application written without IDE, in a simple text editor and compiled in command line. Its goal is to understand how to create Android application from scratch, its structure, and necessary tools.

The project is based on this article on Russian and this article on English.

All binary output files are kept in the repo to let you completely understand the project.

Steps to repeat the project

1. Install JDK and Android SDK.

2. Create folder structure for the project.

│   AndroidManifest.xml
├───bin
├───obj
├───res
│   ├───layout
│   │       activity_main.xml
│   └───values
│           strings.xml
│
└───src
    └───ru
        └───coffeeplanter
            └───minimum
                    MainActivity.java

3. Create AndroidManifest file.

<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="ru.coffeeplanter.minimum">
	<uses-sdk android:targetSdkVersion="25"/>
	<application android:label="Minimum">
		<activity android:name=".MainActivity">
			<intent-filter>
				<action android:name="android.intent.action.MAIN"/>
				<category android:name="android.intent.category.LAUNCHER"/>
			</intent-filter>
		</activity>
	</application>
</manifest>

4. Create resources files.

activity_main.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:layout_gravity="center"
	android:gravity="center">

	<TextView
		android:id="@+id/label_textview"
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:layout_margin="16dp"
		android:gravity="center"
		android:text="@string/text_label"
		android:textSize="24sp"/>

</LinearLayout>

strings.xml:

<resources>
	<string name="text_label">This is the app\nwritten in a simple text editor,\nwithout Android Studio\nor any other IDE.\nEnjoy! :-)</string>
</resources>

5. Write Java code.

package ru.coffeeplanter.minimum;

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class MainActivity extends Activity {

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

}

6. Choose platform and tools version. This project uses 25.0.2 version.

7. Create R.java class file by this command.

<PATH_TO_YOUR_ANDROID_SDK>/build-tools/25.0.2/aapt
	package
	-f
	-m
	-S <PATH_TO_YOUR_PROJECT>/res
	-J <PATH_TO_YOUR_PROJECT>/src
	-M <PATH_TO_YOUR_PROJECT>/AndroidManifest.xml
	-I <PATH_TO_YOUR_ANDROID_SDK>/platforms/android-25/android.jar

8. Compile the project to java binary files.

javac
	-source 7
	-target 7
	-verbose
	-d <PATH_TO_YOUR_PROJECT>/obj
	-classpath <PATH_TO_YOUR_ANDROID_SDK>/platforms/android-25/android.jar:<PATH_TO_YOUR_PROJECT>/obj
	-sourcepath <PATH_TO_YOUR_PROJECT>/src
	<PATH_TO_YOUR_PROJECT>/src/ru/coffeeplanter/minimum/*.java

9. Create dex file for Android Java machine. Use here absolute path, otherwise it can an error occur.

<PATH_TO_YOUR_ANDROID_SDK>/build-tools/25.0.2/dx
	--dex
	--verbose
	--output=<PATH_TO_YOUR_PROJECT>/bin/classes.dex
	<PATH_TO_YOUR_PROJECT>/obj

10. Make unsigned apk file. Delete existing AndroidTest.unsigned.apk and AndroidTest.signed.apk files before running this command.

<PATH_TO_YOUR_ANDROID_SDK>/build-tools/25.0.2/aapt
	package
	-f
	-M <PATH_TO_YOUR_PROJECT>/AndroidManifest.xml
	-S <PATH_TO_YOUR_PROJECT>/res
	-I <PATH_TO_YOUR_ANDROID_SDK>/platforms/android-25/android.jar
	-F <PATH_TO_YOUR_PROJECT>/bin/AndroidTest.unsigned.apk
	<PATH_TO_YOUR_PROJECT>/bin

11. Generate keystore file, if you don't have it.

keytool
	-genkey
	-validity 10000
	-dname "CN=AndroidDebug, O=Android, C=US"
	-keystore <PATH_TO_YOUR_KEYSTORE>/AndroidTest.keystore
	-storepass <YOUR_STORE_PASSWORD>
	-keypass <YOUR_KEY_PASSWORD>
	-alias <YOUR_KEY_NAME>
	-keyalg RSA
	-v
	-keysize 2048

12. Sign your project with the keystore file.

jarsigner
	-sigalg SHA1withRSA
	-digestalg SHA1
	-keystore <PATH_TO_YOUR_KEYSTORE>/AndroidTest.keystore
	-storepass <YOUR_STORE_PASSWORD>
	-keypass <YOUR_KEY_PASSWORD>
	-signedjar %DEV_HOME%/bin/AndroidTest.signed.apk
	<PATH_TO_YOUR_PROJECT>/bin/AndroidTest.unsigned.apk
	<YOUR_KEY_NAME>

13. Install the compiled and signed app on a phone or emulator.

<PATH_TO_YOUR_ANDROID_SDK>/platform-tools/adb uninstall ru.coffeeplanter.minimum
<PATH_TO_YOUR_ANDROID_SDK>/platform-tools/adb install <PATH_TO_YOUR_PROJECT>/bin/AndroidTest.signed.apk
<PATH_TO_YOUR_ANDROID_SDK>/platform-tools/adb shell am start ru.coffeeplanter.minimum/ru.coffeeplanter.minimum.MainActivity

Screenshot