Universal Image Loader for Android

This project aims to provide a reusable instrument for asynchronous image loading, caching and displaying. It is originally based on Fedor Vlasov's project and has been vastly refactored and improved since then.

Features

Multithread image loading
Possibility of wide tuning ImageLoader's configuration (thread executors, downlaoder, decoder, memory and disc cache, display image options, and others)
Possibility of image caching in memory and/or on device's file sysytem (or SD card)
Possibility to "listen" loading process
Possibility to customize every display image call with separated options
Widget support

Android 2.0+ support

Downloads

universal-image-loader-1.8.3.jar (library; contains *.class files)
universal-image-loader-1.8.3-sources.jar (sources; contains *.java files)
universal-image-loader-1.8.3-javadoc.jar (Java docs; contains *.html files)
universal-image-loader-1.8.3-with-sources.jar (library with sources inside; contains *.class and *.java files)
Prefer to use this JAR so you can see Java docs in Eclipse tooltips.
universal-image-loader-sample-1.8.3.apk (sample application)

Latest snapshot of the library - here

Documentation*

Universal Image Loader. Part 1 - Introduction [RU | EN]
Universal Image Loader. Part 2 - Configuration [RU | EN]
Universal Image Loader. Part 3 - Usage [RU | EN]

(*) a bit outdated

Changelog

User Support

Look into Useful Info
Search problem solution on StackOverFlow
Ask your own question on StackOverFlow.
Be sure to mention following information in your question:

UIL version (e.g. 1.8.3)
Android version tested on (e.g. 2.1)
your configuration (ImageLoaderConfiguration)
display options (DisplayImageOptions)
getView() method code of your adapter (if you use it)
XML layout of your ImageView you load image into

Bugs and feature requests put here.
If you have some issues on migration to newer library version - be sure to ask for help here

Quick Setup

1. Include library

Manual:

Download JAR
Put the JAR in the libs subfolder of your Android project

Maven dependency:

<dependency>
	<groupId>com.nostra13.universalimageloader</groupId>
	<artifactId>universal-image-loader</artifactId>
	<version>1.8.3</version>
</dependency>

2. Android Manifest

<manifest>
	<uses-permission android:name="android.permission.INTERNET" />
	<!-- Include next permission if you want to allow UIL to cache images on SD card -->
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
	...
	<application android:name="MyApplication">
		...
	</application>
</manifest>

3. Application class

public class MyApplication extends Application {
	@Override
	public void onCreate() {
		super.onCreate();

		// Create global configuration and initialize ImageLoader with this configuration
		ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(getApplicationContext())
			...
			.build();
		ImageLoader.getInstance().init(config);
	}
}

Configuration and Display Options

ImageLoader Configuration (ImageLoaderConfiguration) is global for application.
Display Options (DisplayImageOptions) are local for every display task (ImageLoader.displayImage(...)).

Configuration

All options in Configuration builder are optional. Use only those you really want to customize.
See default values for config options in Java docs for every option.

// DON'T COPY THIS CODE TO YOUR PROJECT! This is just example of ALL options using.
File cacheDir = StorageUtils.getCacheDirectory(context);
ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(context)
		.memoryCacheExtraOptions(480, 800) // default = device screen dimensions
		.discCacheExtraOptions(480, 800, CompressFormat.JPEG, 75)
		.taskExecutor(AsyncTask.THREAD_POOL_EXECUTOR)
		.taskExecutorForCachedImages(AsyncTask.THREAD_POOL_EXECUTOR)
		.threadPoolSize(3) // default
		.threadPriority(Thread.NORM_PRIORITY - 1) // default
		.tasksProcessingOrder(QueueProcessingType.FIFO) // default
		.denyCacheImageMultipleSizesInMemory()
		.memoryCache(new LruMemoryCache(2 * 1024 * 1024))
		.memoryCacheSize(2 * 1024 * 1024)
		.discCache(new UnlimitedDiscCache(cacheDir)) // default
		.discCacheSize(50 * 1024 * 1024)
		.discCacheFileCount(100)
		.discCacheFileNameGenerator(new HashCodeFileNameGenerator()) // default
		.imageDownloader(new BaseImageDownloader(context)) // default
		.imageDecoder(new BaseImageDecoder()) // default
		.defaultDisplayImageOptions(DisplayImageOptions.createSimple()) // default
		.enableLogging()
		.build();

Display Options

Display Options can be applied to every display task (ImageLoader.displayImage(...) call).

Note: If Display Options wasn't passed to ImageLoader.displayImage(...)method then default Display Options from configuration (ImageLoaderConfiguration.defaultDisplayImageOptions(...)) will be used.

// DON'T COPY THIS CODE TO YOUR PROJECT! This is just example of ALL options using.
DisplayImageOptions options = new DisplayImageOptions.Builder()
		.showStubImage(R.drawable.ic_stub)
		.showImageForEmptyUri(R.drawable.ic_empty)
		.showImageOnFail(R.drawable.ic_error)
		.resetViewBeforeLoading()
		.delayBeforeLoading(1000)
		.cacheInMemory()
		.cacheOnDisc()
		.preProcessor(...)
		.postProcessor(...)
		.extraForDownloader(...)
		.imageScaleType(ImageScaleType.IN_SAMPLE_POWER_OF_2) // default
		.bitmapConfig(Bitmap.Config.ARGB_8888) // default
		.decodingOptions(...)
		.displayer(new SimpleBitmapDisplayer()) // default
		.handler(new Handler()) // default
		.build();

Usage

Acceptable URIs examples

String imageUri = "http://site.com/image.png"; // from Web
String imageUri = "file:///mnt/sdcard/image.png"; // from SD card
String imageUri = "content://media/external/audio/albumart/13"; // from content provider
String imageUri = "assets://image.png"; // from assets
String imageUri = "drawable://" + R.drawable.image; // from drawables (only images, non-9patch)

NOTE: Use drawable:// only if you really need it! Always consider the native way to load drawables - ImageView.setImageResource(...) instead of using of ImageLoader.

Simple

// Load image, decode it to Bitmap and display Bitmap in ImageView
imageLoader.displayImage(imageUri, imageView);

// Load image, decode it to Bitmap and return Bitmap to callback
imageLoader.loadImage(imageUri, new SimpleImageLoadingListener() {
	@Override
	public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
		// Do whatever you want with Bitmap
	}
});

Complete

// Load image, decode it to Bitmap and display Bitmap in ImageView
imageLoader.displayImage(imageUri, imageView, displayOptions, new ImageLoadingListener() {
	@Override
	public void onLoadingStarted(String imageUri, View view) {
		...
	}
	@Override
	public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
		...
	}
	@Override
	public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
		...
	}
	@Override
	public void onLoadingCancelled(String imageUri, View view) {
		...
	}
});

// Load image, decode it to Bitmap and return Bitmap to callback
ImageSize targetSize = new ImageSize(120, 80); // result Bitmap will be fit to this size
imageLoader.loadImage(imageUri, targetSize, displayOptions, new SimpleImageLoadingListener() {
	@Override
	public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
		// Do whatever you want with Bitmap
	}
});

ImageLoader Helpers

Other useful methods and classes to consider.

ImageLoader |
			| - getMemoryCache()
			| - clearMemoryCache()
			| - getDiscCache()
			| - clearDiscCache()
			| - denyNetworkDownloads(boolean)
			| - handleSlowNetwork(boolean)
			| - pause()
			| - resume()
			| - stop()
			| - destroy()
			| - getLoadingUriForView(ImageView)
			| - cancelDisplayTask(ImageView)

MemoryCacheUtil |
				| - findCachedBitmapsForImageUri(...)
				| - findCacheKeysForImageUri(...)
				| - removeFromCache(...)

DiscCacheUtil |
			  | - findInCache(...)
			  | - removeFromCache(...)

StorageUtils |
			 | - getCacheDirectory(Context)
			 | - getIndividualCacheDirectory(Context)
			 | - getOwnCacheDirectory(Context, String)

PauseOnScrollListener

Also look into more detailed Library Map

Useful Info

Caching is NOT enabled by default. If you want loaded images will be cached in memory and/or on disc then you should enable caching in DisplayImageOptions this way:

// Create default options which will be used for every 
//  displayImage(...) call if no options will be passed to this method
DisplayImageOptions defaultOptions = new DisplayImageOptions.Builder()
			...
            .cacheInMemory()
            .cacheOnDisc()
            ...
            .build();
ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(getApplicationContext())
            ...
            .defaultDisplayImageOptions(defaultOptions)
            ...
            .build();
ImageLoader.getInstance().init(config); // Do it on Application start

// Then later, when you want to display image
ImageLoader.getInstance().displayImage(imageUrl, imageView); // Default options will be used

or this way:

DisplayImageOptions options = new DisplayImageOptions.Builder()
			...
            .cacheInMemory()
            .cacheOnDisc()
            ...
            .build();
ImageLoader.getInstance().displayImage(imageUrl, imageView, options); // Incoming options will be used

If you enabled disc caching then UIL try to cache images on external storage (/sdcard/Android/data/[package_name]/cache). If external storage is not available then images are cached on device's filesytem. To provide caching on external storage (SD card) add following permission to AndroidManifest.xml:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

How UIL define Bitmap size needed for exact ImageView? It searches defined parameters:

Get actual measured width and height of ImageView
Get android:layout_width and android:layout_height parameters
Get android:maxWidth and/or android:maxHeight parameters
Get maximum width and/or height parameters from configuration (memoryCacheExtraOptions(int, int) option)
Get width and/or height of device screen

So try to set android:layout_width|android:layout_height or android:maxWidth|android:maxHeight parameters for ImageView if you know approximate maximum size of it. It will help correctly compute Bitmap size needed for this view and save memory.

If you often got OutOfMemoryError in your app using Universal Image Loader then try next (all of them or several):

Reduce thread pool size in configuration (.threadPoolSize(...)). 1 - 5 is recommended.
Use .bitmapConfig(Bitmap.Config.RGB_565) in display options. Bitmaps in RGB_565 consume 2 times less memory than in ARGB_8888.
Use .memoryCache(new WeakMemoryCache()) in configuration or disable caching in memory at all in display options (don't call .cacheInMemory()).
Use .imageScaleType(ImageScaleType.IN_SAMPLE_INT) in display options. Or try .imageScaleType(ImageScaleType.EXACTLY).
Avoid using RoundedBitmapDisplayer. It creates new Bitmap object with ARGB_8888 config for displaying during work.

For memory cache configuration (ImageLoaderConfiguration.memoryCache(...)) you can use already prepared implementations.

Cache using only strong references:
- LruMemoryCache (Least recently used bitmap is deleted when cache size limit is exceeded) - Used by default for API >= 9
Caches using weak and strong references:
- UsingFreqLimitedMemoryCache (Least frequently used bitmap is deleted when cache size limit is exceeded)
- LRULimitedMemoryCache (Least recently used bitmap is deleted when cache size limit is exceeded) - Used by default for API < 9
- FIFOLimitedMemoryCache (FIFO rule is used for deletion when cache size limit is exceeded)
- LargestLimitedMemoryCache (The largest bitmap is deleted when cache size limit is exceeded)
- LimitedAgeMemoryCache (Decorator. Cached object is deleted when its age exceeds defined value)
Cache using only weak references:
- WeakMemoryCache (Unlimited cache)

For disc cache configuration (ImageLoaderConfiguration.discCache(...)) you can use already prepared implementations:

UnlimitedDiscCache (The fastest cache, doesn't limit cache size) - Used by default
TotalSizeLimitedDiscCache (Cache limited by total cache size. If cache size exceeds specified limit then file with the most oldest last usage date will be deleted)
FileCountLimitedDiscCache (Cache limited by file count. If file count in cache directory exceeds specified limit then file with the most oldest last usage date will be deleted. Use it if your cached files are of about the same size.)
LimitedAgeDiscCache (Size-unlimited cache with limited files' lifetime. If age of cached file exceeds defined limit then it will be deleted from cache.)

NOTE: UnlimitedDiscCache is 30%-faster than other limited disc cache implementations.

To display bitmap (DisplayImageOptions.displayer(...)) you can use already prepared implementations:

RoundedBitmapDisplayer (Displays bitmap with rounded corners)
FadeInBitmapDisplayer (Displays image with "fade in" animation)

To avoid list (grid, ...) scrolling lags you can use PauseOnScrollListener:

boolean pauseOnScroll = false; // or true
boolean pauseOnFling = true; // or false
PauseOnScrollListener listener = new PauseOnScrollListener(imageLoader, pauseOnScroll, pauseOnFling);
listView.setOnScrollListener(listener);

Applications using Universal Image Loader

Donation

You can support the project and thank the author for his hard work :)

PayPal - nostra.uil[at]gmail[dot]com
WebMoney - Z417203268219
GitTip - nostra13

License

If you use Universal Image Loader code in your application you should inform the author about it ( email: nostra13[at]gmail[dot]com ) like this:

Subject: UIL usage notification
Text: I use Universal Image Loader <lib_version> in <application_name> - http://link_to_google_play. I [allow | don't allow] to mention my app in section "Applications using Universal Image Loader" on GitHub.

Copyright 2011-2013 Sergey Tarasevich

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

sungeuns/Android-Universal-Image-Loader