Hello android

Post on 14-Aug-2015

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Transcript of Hello android

Hello, Android!

Android Architecture● Android framework

○ Activity manager○ Location manager○ etc.

● Native libraries○ Open GL/ES○ Media framework○ etc.

● Android runtime○ Dalvik○ ART(Android runtime)

● HAL○ Hardware abstraction layer

● Linux kernel

● Tool: Android Studio (ver1.3)● Needs…

o 2GB RAM - minimumo 400MB Hard disko JDK 7

● Downloado Windows:

https://dl.google.com/dl/android/studio/install/1.2.2.0/android-studio-bundle-141.1980579-windows.exe

o Mac:https://dl.google.com/dl/android/studio/install/1.2.2.0/android-studio-ide-141.1980579-mac.dmg

Setting

First Project● manifest

○ describe components○ declare permission○ list linked libraries○ etc.

● java● res

○ Image files○ Layout XML file○ Other resources

● gradle○ Build system of Android Studio○ Declare options for application build

Hello world!● Activity

○ Component that provides screen which user could interact to do something with app.

● Layout○ visual structure for user interface

● UI Components○ Items for interact / express on activity○ Text, button, checkbox, etc.

● Action bar○ Area on top of single screen○ Contains button for sub menu

Activity life cycle

Java● Extends Activity to create activity class

○ Override onCreate, onPause, onDestroy, etc● setContentView(...)

○ set target layout XML file to connect with current Acvitity

Layout● User interface layout

○ Relative / Linear / Frame ...● User interface components

○ Button, text, switch, toggle...

Manifest● Present essential info about app● Declares package name / components / permissions

Gradle● gradle file for setting, project, module● define setting on building application

Activity to activity● Button, Intent

Button● Define onClick method on XML● Implement View.onClickListener

Intent● Abstract description of an

operation to be performed○ Launch activity○ Communicate with

background service

activity_main.xml

MainActivity.java

Activity/UI stack● When new activity starts, previous activiy goes down● Foreground activity are being destroyed when user navigate back

Action bar● Important design elements you can implement for app's activities

Action bar layout● Icon / Setting● app:showAsAction

○ always, ifRoom, withText, never

Action bar control● extends

ActionBarActivity● onCreateOptionMenu

○ Set menu layout● onOptionItemSelected

○ Action for item selection