README.md

FirebaseUI for Android — Storage

Using FirebaseUI to download and display images

Firebase Storage provides secure file uploads and downloads for your Firebase apps, regardless of network quality. You can use it to store images, audio, video, or other user-generated content. Firebase Storage is backed by Google Cloud Storage, a powerful, simple, and cost-effective object storage service.

FirebaseUI provides bindings to download an image file stored in Firebase Storage from a StorageReference and display it using the popular Glide library. This technique allows you to get all of Glide's performance benefits while leveraging Firebase Storage's authenticated storage capabilities.

To load an image from a StorageReference, simply use the FirebaseImageLoader class:

    // Reference to an image file in Firebase Storage
    StorageReference storageReference = ...;

    // ImageView in your Activity
    ImageView imageView = ...;

    // Load the image using Glide
    Glide.with(this /* context */)
            .using(new FirebaseImageLoader())
            .load(storageReference)
            .into(imageView);

Images displayed using FirebaseImageLoader are cached by their path in Firebase Storage, so repeated loads will be fast and conserve bandwidth. For more information on caching in Glide, see this guide.

Known Issues

There is a bug in com.google.firebase:firebase-storage:9.6.1 and earlier that results in excessive logging when downloading images. You may see messages in your logs like this:

W/StorageTask: unable to change internal state to: INTERNAL_STATE_IN_PROGRESS isUser: false from state:INTERNAL_STATE_SUCCESS

In production this could slow your app down if you are downloading many images. The suggested workaround is to disable logging in production by adding the following lines to your ProGuard configuration (proguard-rules.pro):

-assumenosideeffects class android.util.Log {
    public static int w(...);
    public static int d(...);
    public static int v(...);
}

This will disable calls to Log.w(), Log.d(), and Log.v() but preserve log calls at the INFO and ERROR levels. Note that this will only be effective when using proguard-android-optimize.txt as the default ProGuard file in build.gradle.