devfest sul 2014 - android 4 lazy ios devs

Give yourself to the Dark Side!

Jackson F. de A. Mafra

http://developer.android.com/design/index.html

follow this, seriously!

Understand some of the key UI paradigms in use on Android today: the action bar, the overflow menu, the back button, the share action,

and more.

No More Menu Button

New Buttons

Notifications

Navigation

ActionBar

ActionBar

MultiPane

Dialogs

Android is not iOS

Android is not iOS

IDE

Android Studio

or

(Eclipse ADT plugin)

Android SDK and AVD Manager

Language Application Structure

There are many differences between Objective-C and Java

Java

Say what you will about Java, in the end it's just another language. Be thankful there is no J2EE

in sight.

Language Application Structure

Referencing this.object will not call your custom getter. You must use this.getObject.

Language Application Structure

Java methods are typically written as actions or queries, such as getCell(), instead of

cellForRowAtIndexPath:.

Simulator

I used to think the iOS simulator was painful, now I realise it's pretty awesome.

Skip the Android simulator all together and deploy to a real device, or be prepared to spend

a lot of time waiting.

Consider to use Genymotion, a fastest Android emulator for app testing and presentation.

Project Structure

Android applications are primarily broken into two sections, the first of which is the Java

source code.

Project Structure

The source code is structured via the Java package hierarchy, and it can be structured as you please. However, a common practice is to

use top-level categories for activities, fragments, views, adapters, and data (models

and managers).

Project Structure

The second major section is the res folder, short for ‘resource’ folder.

Project Structure

The res folder is a collection of images, XML layout files, and XML value files that make up

the bulk of the non-code assets.

Project Structure

Android uses Layouts which are xml. They are completely independent from each other.

Android Studio also has a nice WYSIWYG editor

Project Structure

On iOS, images are either @2x or not, but on Android there are a number of screen density

folders to consider.

Project Structure

Android uses folders to arrange images, strings, and other values for screen density.

Project Structure

One last correlation in project structure is the AndroidManifest.xml file.

Project Structure

This file is the equivalent of the Project-Info.plist file on iOS, and it stores information for

activities, application names, and set Intents (system-level events) that the application can

handle.

Activities

Activities are the basic visual unit of an Android app, just as UIViewControllers are

the basic visual component on iOS.

Activities

Instead of a UINavigationController, the Android OS keeps an activity stack that it

manages.

Activities

In essence, the activity lifecycle is very similar to the UIViewController lifecycle.

Activities

Fragments

The Fragment concept is unique to Android and came around somewhat recently in

Android 3.0 (2010).

Fragments

Fragments are mini controllers that can be instantiated to fill activities.

Fragments

Also note that fragments do not have their own contexts and they rely heavily on activities for

their connection to the application’s state.

Fragments

Tablets are a great fragment use case example: you can place a list fragment on the left and a

detail fragment on the right.

Fragments

Fragments allow you to break up your UI and controller logic into smaller, reusable chunks.

List Views and Adapters

ListViews are the closest approximation to UITableView on Android, and they are one of the most common components that you will

use.

List Views and Adapters

Like UITableView has a helper view controller, UITableViewController, ListView also has a

helper activity, ListActivity, and a helper fragment, ListFragment.

List Views and Adapters

On Android we don’t have datasources and delegates for ListView.

List Views and Adapters

We have adapters. Adapters come in many forms, but their primary goal is similar to a

datasource and table view delegate all in one.

List Views and Adapters

Adapters take data and adapt it to populate a ListView by instantiating views the ListView

will display

AsyncTasks

In place of Grand Central Dispatch on iOS, on Android we have access to AsyncTasks.

AsyncTasks

AsyncTasks is a different take on exposing asynchronous tools in a more friendly way.

Layout

The primary structure that you will deal with will be subclasses of ViewGroup –

RelativeLayout, LinearLayout, and FrameLayout are the most common.

Layout

Always work in dp (density-independent pixels) instead of pixels directly.

Data

The Data Storage Options available on Android are also very similar to what is available on iOS

Data

Shared Preferences <-> NSUserDefaults

Data

Saving to and fetching from file structure via the internal or external file storage <-> saving

to the documents directory

Data

SQLite <-> Core Data

Data

Android offers straight access to the SQLite database and returns cursor objects for results

IBOutlet

If you are anything like me you forget to connect IBOutlets at least 50% of the time

every time.

IBOutlet

With Android every view/component has a unique ID, something like:

@+id/myButton

Button button = (Button)findViewById(R.id.myButton);

NSLog

Log seems to be the go to solution here, you can specify debug, verbose etc.

System.out.println(..) also seems to do the job.

Paid Apple $99 developer fee

x

Paid Google $25 developer fee

$25 fee in Play Store.

75% cheaper than Apple's yearly fee.

Payments handled through Google Checkout.

Referenceshttp://www.objc.io/issue-11/android_101_for_ios_developers.html

http://www.bignerdranch.com/blog/learning-android-development-ios-developers-perspective/

http://stuartkhall.com/posts/android-development-tips-for-ios-devs

http://clayallsopp.com/android/9-uploading-to-market.html

http://developer.android.com/design/patterns/pure-android.html

http://www.prnewswire.com/news-releases/strategy-analytics-android-captures-79-percent-share-of-global-smartphone-shipments-in-2013-242563381.html

@jacksonfdam

Thank you