Jul 6 2012

Life Before Loaders (part 1)

This post gives a brief introduction to Loaders and the LoaderManager. The first section describes how data was loaded prior to the release of Android 3.0, pointing out out some of the flaws of the pre-Honeycomb APIs. The second section defines the purpose of each class and summarizes their powerful ability in asynchronously loading data.

This is the first of a series of posts I will be writing on Loaders and the LoaderManager:

If you know nothing about Loaders and the LoaderManager, I strongly recommend you read the documentation before continuing forward.

The Not-So-Distant Past

Before Android 3.0, many Android applications lacked in responsiveness. UI interactions glitched, transitions between activities lagged, and ANR (Application Not Responding) dialogs rendered apps totally useless. This lack of responsiveness stemmed mostly from the fact that developers were performing queries on the UI thread—a very poor choice for lengthy operations like loading data.

While the documentation has always stressed the importance of instant feedback, the pre-Honeycomb APIs simply did not encourage this behavior. Before Loaders, cursors were primarily managed and queried for with two (now deprecated) Activity methods:

Jun 25 2012

Content Providers & Content Resolvers

Content Providers and Content Resolvers are a common source of confusion for beginning Android developers. Further, online tutorials and sample code are not sufficient in describing how the two classes work together to provide access to the Android data model. This post hopes to fill in this gap by explaining their place in the android.content package. It concludes with a walk through the life of a simple query to the Content Resolver.

Jun 18 2012

Why Ice Cream Sandwich Crashes your App

The following question has plagued StackOverflow ever since Ice Cream Sandwich’s initial release:

My application works fine on devices running Android 2.x, but force closes on devices running Honeycomb (3.x) and Ice Cream Sandwich (4.x). Why does this occur?

This is a great question; after all, newer versions of Android are released with the expectation that old apps will remain compatible with new devices. In my experience, there are a couple reasons why this might occur. Most of the time, however, the reason is simple: you are performing a potentially expensive operation on the UI thread.

Jun 14 2012

Ensuring Compatibility with a Utility Class

This post introduces the concept of a utility class and gives a simple example of how you can use one to tidy up your code. As Android projects grow in size, it becomes increasingly important that your code remains organized and well-structured. Providing a utility class for commonly called methods can help tremendously in reducing the complexity of your project, allowing you to structure your code in a readable and easily understandable way.

Jun 13 2012

Designing for Backwards Compatibility

Note: please read this short post before continuing forward.

A common issue in Android development is backwards compatibility. How can we add cool new features from the most recent Android API while still ensuring that it runs correctly on devices running older versions of Android? This post discusses the problem by means of a simple example, and proposes a scalable, well-designed solution.

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Android Design Patterns is a website for developers who wish to better understand the Android application framework. The tutorials here emphasize proper code design and project maintainability.

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Apps by me

Shape Shifter simplifies the creation of AnimatedVectorDrawable path morphing animations. View on GitHub.
2048++ is hands down the cleanest, sleekest, most responsive 2048 app for Android!