Androidify Yourself!
Alexey Buzdin
Aleksey Nikolaenko
@AlexeyBuzdin
@echoAlexey
Google Developers Group
• Place to discuss, learn, and share passion for
technology
• Focused on developer culture & techn...
Today’s agenda
• Setup environment
• Introduction to Android
• Android application
development
• GDG Raffle
http://goo.gl/...
Android Studio
• IntelliJ IDEA based
• Gradle build support
• Comes with Android
SDK
• Layout editor with
preview
and much...
Android platform
• Android is a Linux-based operating system
and a software stack designed for touchscreen
mobile devices
Android Anatomy
Android Runtime
• On Android you develop in Java
• ... but Android does not run Java Bytecode !
Android Runtime
• Custom Virtual Machine. Why?
Constraints
Designed for 64M RAM
No swap
Phone tech v. Desktop
CPU specific...
Anatomy of Android application
• AndroidManifest
• Activities
• Fragments
• Intents
• Services
• Content providers
• Broad...
Android Manifest
• general configuration for your application
• contains all component definitions of your
appication
Activity
• An activity represents a single screen with
a user interface
• An activity is implemented as a subclass of
Acti...
Fragment
• A Fragment represents
a behavior or a portion
of user interface in an
Activity
• Affected by lifecycle of
Activ...
Intent
Intent is used to invoke different
components:
• Start a service
• Launch an activity
• Display a web page
• Broadc...
Service
• Background process that performs long-
running operations or remote processes
• No user interface for service
• ...
Content providers
• Content providers are used to share data
between applications
• Can store data in SQLite, Web and othe...
Broadcast receiver
• Component that responds to system-wide
broadcast announcements (e.g.. Screen is
turns on-off, SMS rec...
Android UI fundamentals
Android UI fundamentals
Screen size
• actual physical size, measured
as the screen's diagonal
• 2.55”, 3.2”, 4.0”, 10.1”, ...
Android UI fundamentals
Screen density
• quantity of pixels within a physical area of the
screen (dots per inch, dpi).
• "...
Android UI fundamentals
Density-independent pixel (dp)
• virtual pixel unit to express layout dimensions or
position in a ...
Android UI fundamentals
Best practices
• Do not use hard-coded pixel values in your
application code
• Use size and densit...
Android resources
Resources
Android supports the externalization of resources
• strings, colors, images, themes, menus, layouts
• system res...
res/ & R
res/
• Generated by ADT Wizard
• Each resource type is stored in a
different subfolder
R.java
• Resources from /r...
Default v. Alternative Resources
• For any type of resource, we can specify default
and multiple alternative resources
• D...
How to specify Alternative Resources
• Create a new directory in res/
• res/<resources_name>-
<config_qualifier>
• <config...
Resource types
• Layouts
• Simple values
– Strings
– Plurals
– Colors
– Dimensions
– Styles
– String or integer arrays
Sto...
Resource types
Styles and Themes
• Let your applications
maintain a consistent
look and feel by
enabling you to
specify th...
Building User Interfaces
View
View
• base class for all visual interface
elements controls, widgets
• an object that draws something on the
screen ...
Android Layouts
• A layout defines the visual
structure for a user interface,
such as the UI for an activity or
app widget...
Layout
Advantages of declaring UI in XML
• Separation of the presentation from the code that
controls its behavior
• modif...
Layout example
ViewGroup
View
Layout types
LinearLayout
• Aligns all children in a single
direction - vertically or horizontally
• All children are stac...
LinearLayout
Layout types
RelativeLayout
• view group that displays child
views in relative positions
• can eliminate nested view
group...
Layout Parameters
Layout Parameters (layout_something)
• parent view group defines layout parameters for
each child view (...
Basic widget toolbox
Questions & Answers
Want to host a workshop or
presentation?
gdgriga@gmail.com
Androidify workshop
Androidify workshop
Upcoming SlideShare
Loading in...5
×

Androidify workshop

246

Published on

Android introduction slides for GDG Riga event

Published in: Software, Technology
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
246
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
6
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Androidify workshop

  1. 1. Androidify Yourself!
  2. 2. Alexey Buzdin Aleksey Nikolaenko @AlexeyBuzdin @echoAlexey
  3. 3. Google Developers Group • Place to discuss, learn, and share passion for technology • Focused on developer culture & technical content • Free as beer
  4. 4. Today’s agenda • Setup environment • Introduction to Android • Android application development • GDG Raffle http://goo.gl/HIYmeC
  5. 5. Android Studio • IntelliJ IDEA based • Gradle build support • Comes with Android SDK • Layout editor with preview and much more…
  6. 6. Android platform • Android is a Linux-based operating system and a software stack designed for touchscreen mobile devices
  7. 7. Android Anatomy
  8. 8. Android Runtime • On Android you develop in Java • ... but Android does not run Java Bytecode !
  9. 9. Android Runtime • Custom Virtual Machine. Why? Constraints Designed for 64M RAM No swap Phone tech v. Desktop CPU specific Oracle JVM problems Memory Hog Slow startup IP licensing restrictions
  10. 10. Anatomy of Android application • AndroidManifest • Activities • Fragments • Intents • Services • Content providers • Broadcast receivers
  11. 11. Android Manifest • general configuration for your application • contains all component definitions of your appication
  12. 12. Activity • An activity represents a single screen with a user interface • An activity is implemented as a subclass of Activity
  13. 13. Fragment • A Fragment represents a behavior or a portion of user interface in an Activity • Affected by lifecycle of Activity • subclass of Fragment
  14. 14. Intent Intent is used to invoke different components: • Start a service • Launch an activity • Display a web page • Broadcast a message
  15. 15. Service • Background process that performs long- running operations or remote processes • No user interface for service • A service is implemented as a subclass of Service • Service can be local (accessed within application) or remote (scope of device)
  16. 16. Content providers • Content providers are used to share data between applications • Can store data in SQLite, Web and other storages and perform CRUD operations with Content providers • subclass of ContentProvider
  17. 17. Broadcast receiver • Component that responds to system-wide broadcast announcements (e.g.. Screen is turns on-off, SMS received, • Broadcast delivered as Intent • Don’t have user interface • Subclass of BroadcastReceiver
  18. 18. Android UI fundamentals
  19. 19. Android UI fundamentals Screen size • actual physical size, measured as the screen's diagonal • 2.55”, 3.2”, 4.0”, 10.1”, ... Android groups into four generalized sizes: • Small • Normal • Large • Xlarge
  20. 20. Android UI fundamentals Screen density • quantity of pixels within a physical area of the screen (dots per inch, dpi). • "low" density screen has fewer pixels • Android groups actual screen densities into four generalized densities: • Low (ldpi, 120) • Medium (mdpi, 160) • High (hdpi, 240) • Extra high (xhdpi, 320)
  21. 21. Android UI fundamentals Density-independent pixel (dp) • virtual pixel unit to express layout dimensions or position in a density-independent way • equivalent to one physical pixel on a 160 dpi screen • px = dp * (dpi / 160) • system transparently handles any scaling of the dp units
  22. 22. Android UI fundamentals Best practices • Do not use hard-coded pixel values in your application code • Use size and density-specific resources • Use wrap_content, match_parent, or the dp unit for layout dimensions • Test Your Application on Multiple Screens
  23. 23. Android resources
  24. 24. Resources Android supports the externalization of resources • strings, colors, images, themes, menus, layouts • system resources Why? • easier to maintain, update, and manage • easier to define alternative resource values for internationalization and to support variations in hardware
  25. 25. res/ & R res/ • Generated by ADT Wizard • Each resource type is stored in a different subfolder R.java • Resources from /res are „indexed“ by ADT or aapt tool • Enables to reference resources in code
  26. 26. Default v. Alternative Resources • For any type of resource, we can specify default and multiple alternative resources • Default resources are used regardless of the device configuration when no alternative resources match the current configuration • Alternative resources are designed for use with a specific configuration
  27. 27. How to specify Alternative Resources • Create a new directory in res/ • res/<resources_name>- <config_qualifier> • <config_qualifier> specifies a configuration for which these resources are to be used • Save your alternative resources in new directory and name it as the default resource files
  28. 28. Resource types • Layouts • Simple values – Strings – Plurals – Colors – Dimensions – Styles – String or integer arrays Stored within XML files in the res/values folder
  29. 29. Resource types Styles and Themes • Let your applications maintain a consistent look and feel by enabling you to specify the attribute values used by Views • The most common use of is to store the colors and fonts for an application
  30. 30. Building User Interfaces
  31. 31. View View • base class for all visual interface elements controls, widgets • an object that draws something on the screen that the user can interact with View Group • extends View class • an object that holds other Views View group is an invisible container that organizes child views, while the child views draw some part of the UI
  32. 32. Android Layouts • A layout defines the visual structure for a user interface, such as the UI for an activity or app widget. • Can be defined in XML or programmatically during runtime. • XML layouts stored in res/layout folder and are qualified as resource
  33. 33. Layout Advantages of declaring UI in XML • Separation of the presentation from the code that controls its behavior • modify UI without having to modify source code • create XML layouts for different screen orientations, different device screen sizes, and different languages • Easier to visualize the structure of your UI • Easier to design/debug UI • Visualizer tool (ADT)
  34. 34. Layout example ViewGroup View
  35. 35. Layout types LinearLayout • Aligns all children in a single direction - vertically or horizontally • All children are stacked one after the other • Layout weight (android: layout_weight) assigns an "importance" value to a view in terms of how much space is should occupy on the screen
  36. 36. LinearLayout
  37. 37. Layout types RelativeLayout • view group that displays child views in relative positions • can eliminate nested view groups and keep your layout hierarchy flat, that improves performance • specify the location of child objects relative to each other (child A to the left of child B) or to the parent
  38. 38. Layout Parameters Layout Parameters (layout_something) • parent view group defines layout parameters for each child view (including the child view group) • child element must define LayoutParams that are appropriate for its parent
  39. 39. Basic widget toolbox
  40. 40. Questions & Answers
  41. 41. Want to host a workshop or presentation? gdgriga@gmail.com
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×