Android App Development 20150528

1. Android App Development 5
28 May, 2015

2.  Add a New Button
 LinearLayout (vertical)
 Starting Another Activity
 Create the Second Activity
 goNextActivity() Method
 Build an Intent
 Add a startActivity Method
Last Workshop

3. Adding an Image
Adding Audio
Today’s Contents

4. Step 1 : Preparing an Image file
Step 2 : Adding <ImageView>
Adding an Image

5.  Supported Image Formats
 BMP / JPG / PNG / GIF
 Image Folder
 Put your image file into folder res/drawable
Step 1 : Preparing an Image file
Adding an Image
image01.jpg (300 x 255)

6.  Edit res/layout/activity_my.xml
 Add <ImageView> element
Step 2 : Adding <ImageView>
Adding an Image
res/drawable folder file extension can be omitted

7. Adding an Image

8. Adding Audio

9.  SoundPool
 an Android library
specifically targeted for playing short audio clips
 Supported Audio Formats
 wav / ogg
Adding Audio
sound01.wav
MediaPlayer
for longer sound files or streams

10. Step 1 : Preparing an Audio file
Step 2 : Declaring Variables
Step 3 : Loading an Audio file
Step 4 : Playing an Audio file
Step 5 : Releasing SoundPool resources
Adding Audio

11.  Add raw folder under res folder
 Put your audio file into folder res/raw
Step 1 : Preparing an Audio file
Adding Audio

12.  Edit MyActivity.java
 Declare 2 Variables in MyActivity class
Step 2 : Declaring Variables
Adding Audio
…
}
*To use SoundPool, import SoundPool class

13.  Edit MyActivity.java
 Add onResume() method to MyActivity class
Step 3 : Loading an Audio file
Adding Audio
res/raw folder
file extension can be omitted
system calls this method when the activity comes to the foreground

14.  Edit MyActivity.java
 Add playAudio() method to MyActivity class
 Edit res/layout/activity_my.xml
 Add onClick attribute to ImageView element
Step 4 : Playing an Audio file
Adding Audio

15.  Edit MyActivity.java
 Add onPause() method to MyActivity class
Step 5 : Releasing SoundPool resources
Adding Audio
system calls this method when another activity is started

16. Adding Audio

17. Wrap Up for Today
 Adding an Image
 ImageView element
 Adding Audio
 SoundPool

18.  Follow the link and read the articles
 Android Activity Lifecycle
 http://www.codelearn.org/android-tutorial/android-activity
Assignment

19. fin.
2more workshops left.