android development: build android app from scratch

Android Development: Build Android App from Scratch

Taufan Erfiyanto, ST.

A one day workshop of Android Development at Phetchaburi Rajabhat University, Thailand. In collaboration with Gunadarma University and Phetchaburi Rajabhat University.

Founder of pongodev.com, mobile application developer and the man who responsible to deliver the app with beautiful user interface and insure that it generates many download with marketing strategy.

About

taufan@pongodev.com

twitter.com/taufan20

linkedin.com/in/taufan20

portfolio

Crowdfunding mobile-based application that allows users raise funds for humanity and environmental activities. Donation can be done via smartphone credit and transfer.

http://donasia.org

What do you know about Android?

1 billion Android population.

Horace dediu

1.43 million apps on Google Play in 2014.

appFigures

268 billion times downloads and generate revenue $77

billion in 2017.

Gartner

Available in all devices, smartphone, watch, tv,

and car.

Android Development Tools

1. Java Development Kitdownload: bit.ly/JDKandroid

2. Android Studio and SDK Toolsdownload: bit.ly/AnStudio

Creating New Project

1. Select Start a new Android Studio Project on Welcome window.

2. Type application name and company domain.

3. Select Device Type and Minimum SDK.

4. Select Blank Activity in Activity type.

5. Name your first activity and layout file.

Understand the Project Structure

1. Android project consist of manifest, java, res, and Gradle directories.

2. Activity works as a page in application. Located in java directory.

3. The first method that will be executed when app run is onCreate().

4. Every activity has layout file as its user interface. located in res/layout directory.

5. To connect layout and activity, setContentView() must be defined.

6. Every activity created must be registered to AndroidManifest.xml.

Creating Android Emulator

1. Open AVD Manager via Tools > Android.

2. Select Create Virtual Device… button.

3. Select device type and screen resolution.

4. Select Android version.

5. Type emulator name.

6. Select the emulator name and click Launch icon.

Running Android Project on Emulator

1. Select Run > Run ‘app’.

2. Select Launch emulator and emulator name. Or select Choose a running device if you have

running emulator.

Running Android Project on Android Device

1. On Android device, select Settings > Developer Options. Enable USB Debugging.

Note: Android 4.2 and newer go to Settings > About phone and tap Build number seven times.

2. Connect Android device to the computer via usb cable.

3. Select Run > Run ‘app’.

2. Select Choose a running device and device name.

Note: some device require a driver from its factory to be installed on the computer.

Creating User Interface

1. Open your xml layout file in layout directory.

2. Drag widget on Palette section to device screen on the right side.

3. Configure widget properties via properties window on the right bottom corner of the window.

Note: important properties are id, layout_width, and layout_height.

Manipulating Widget

1. Open activity file that use activity_main.xml layout in java directory.

2. Create objects of the widgets in activity file that you want to manipulate.

3. Connect the objects with widget id in xml layout inside onCreate() method.

4. Add event handling to button object.

5. manipulate your widget when button click inside onClick() method.

Creating To Do List App

1. Modify the user interface as seen above. Consist of EditText, Button, and ListView.

2. Create objects of EditText, Button, and ListView in activity file.

3. Connect the objects with widget id in xml layout.

4. Create ArrayAdapter object and ArrayList variable above onCreate() method.

5. Define adapter parameter and set it to list object using setAdapter().

6. Add button event handling to add data to the list.

7. Run the project to see the result.

Integrating SQLite Database to Android

Project

1. Create new directory under app/src/main directory via window explorer. name it as assets.

2. Create database to store data inside assets directory using sqlitebrowser.

Note: database of to do list app can be download at bit.ly/dbTodo and sqlitebrowser can be download at bit.ly/sqliteAndroid.

3. Create new java file inside app/java/package.name.

4. Name it as DBHelper.Note: Download DBHelper.java file at bit.ly/DBHelper

and copy the code to your DBHelper.java.

5. Define database path, database name, table name and fields.

Note: SQLiteOpenHelper is used for creating, opening, and upgrading database. SQLiteDatabase is used for communicating data of database.

6. Create object of DBHelper class and ArrayList variable in Activity file.

7. Connect dbhelper object with it class and call createDataBase() and openDataBase() method.

8. Create displayData() method before closing bracket to display data from database with

getAllNotes() method.

9. And call displayData() method after openDataBase() method.

10. Call addNote() and displayData() method inside button event handling to add data to

databse and display them after added.

11. Run the project to see the result.

12. Add new arraylist variable to store note id.

13. Do not forget to clear ids and add ids in displayData() method.

14. Create list event handling to delete note with item on list click.

15. Call removeNote() method to remove data from database and displayData() method to re-

display data on the list.

16. Run the project again to see the result.

What do you need to know next to mastering Android development?

FragmentsMaterial Design

Hardware Integration

Multiple Screen Support

Connect to Web Services

–Joel Spolsky, Stack Exchange

Nothing works better than just improving your product.