Basic Android #1Build your simple app

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Build Simple App

download android sdk

create your first app

http://developer.android.com/sdk/index.html#mac-bundle

Step 1

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Structure of project

src

assets

libs

res *

AndroidManifest.xml

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Drawable

xhdpi 2.0

hdpi 1.5

mdpi 1.0

ldpi 0.75

This means that if you generate a 200x200 image for xhdpi devices, you should generate the same resource in 150x150 for hdpi, 100x100 for mdpi, and 75x75 for ldpi devices.

ref:http://developer.android.com/training/basics/supporting-devices/screens.html

Nexus 7

true tab3g

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AndroidManifest.xmlเวลาอัพขึ้น market ต้องมากขึ้นเรื่อยๆ

แสดง icon ของApp

Activity นี้จะแสดงแต่แนวตั้ง

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Life Cycle Activity

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Activity?

จะมีแต ่view เดี่ยวๆโปรแกรมทํางานไม่ได้ if it has a UI, it’ll have at least one Activity

Relationship between an Activity with a UI screen ---> MVC paradigm (ref: Android in action )

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A

B

A

ActivityIntent intent = new Intent(this, A.class);startActivity(intent);

Intent intent = new Intent(this, B.class);startActivity(intent);

Intent intent = new Intent(this, A.class);startActivity(intent);

ถ้ากดBack สองที ?

show A1

show B1

show A

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setcontentView(R.layout.list_item_icom);ImageView imgIcon = (ImageView)findViewById(R.id.icon);

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LayoutLinearLayout RelativeLayout

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• Measure: 0.977ms• Layout: 0.167ms• Draw: 2.717ms

The timings for rendering a complete list item using this layout are:

• Measure: 0.598ms• Layout: 0.110ms• Draw: 2.146ms

http://developer.android.com/training/improving-layouts/optimizing-layout.html

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Most of this time difference is due to the use of layout_weight in the LinearLayout design,

which can slow down the speed of measurement

http://developer.android.com/training/improving-layouts/optimizing-layout.html

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Thank you for your Attention

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