Placeholder glide android studio

Glide allows users to specify three different placeholders that are used under different circumstances:

Placeholder

Placeholders are Drawables that are shown while a request is in progress. When a request completes successfully, the placeholder is replaced with the requested resource. If the requested resource is loaded from memory, the placeholder may never be shown. If the request fails and an error Drawable is not set, the placeholder will continue to be displayed. Similarly if the requested url/model is null and neither an error Drawable nor a fallback Drawable are set, the placeholder will also continue to be displayed.

Error

Error Drawables are shown when a request permanently fails. Error Drawables are also shown if the requested url/model is null and no fallback Drawable is set

Fallback

Fallback Drawables are shown when the requested url/model is null . The primary purpose of fallback Drawables is to allow users to indicate whether or not null is expected. For example, a null profile url may indicate that the user has not set a profile photo and that a default should be used. However, null may also indicate that meta-data is invalid or couldn’t be retrieved. By default Glide treats null urls/models as errors, so users who expect null should set a fallback Drawable.

Are placeholders loaded asynchronously?

No. Placeholders are loaded from Android resources on the main thread. We typically expect placeholders to be small and easily cacheable by the system resource cache.

Are Transformations applied to placeholders?

No. Transformations are applied only to the requested resource, not to any placeholder.

It’s inefficient to include resources that have to be transformed at runtime in your application. You’re almost always better off including a version of the resource that’s exactly the size and shape that you need. If you’re loading circular images for example, you may want to include circular placeholder resources with your application. Alternatively you could also consider a custom View to clip your placeholder in the same manner as your Transformation.

Is it ok to use the same Drawable as a placeholder in multiple Views?

Usually, but not always. Any non-stateful Drawable (like BitmapDrawable) is typically ok to display in multiple views at once. Stateful Drawables however, are typically not safe to display in multiple views at the same time because multiple Views will mutate the state at once. For stateful Drawables, pass in a resource id, or use newDrawable() to pass in a new copy to each request.

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Displaying Images with the Glide Library

Glide is an Image Loader Library for Android developed by bumptech and is a library that is recommended by Google. It has been used in many Google open source projects including Google I/O 2014 official application. It provides animated GIF support and handles image loading/caching.

Add to your app/build.gradle file:

Make sure to create a MyAppGlideModule that simply extends from AppGlideModule and has the @GlideModule annotation. For now, the class is empty but later we will show how it can be used to set the default image resolution. If you upgrading from Glide v3, make sure you follow this step too:

Make sure to sync your project to Gradle before continuing, since Glide needs to generate the necessary code to invoke GlideApp.with() in Android Studio.

If you are migrating from Glide v3, make sure to review this guide. Instead of Glide.with() , you will need to use GlideApp.with() :

Resizing images with:

Placeholder and error images:

Cropping images with:

Modify your MyAppGlideModule to override applyOptions:

Ideally, an image’s dimensions would match exactly those of the ImageView in which it is being displayed, but as this is often not the case, care must be taken to resize and/or scale the image appropriately. Android’s native support for this isn’t robust, especially when displaying very large images (such as bitmaps returned from the camera) in smaller image views, which can often lead to errors (see Troubleshooting).

Glide automatically limits the size of the image it holds in memory to the ImageView dimensions. Picasso has the same ability, but requires a call to fit() . With Glide, if you don’t want the image to be automatically fitted to the ImageView , you can call override(horizontalSize, verticalSize) . This will resize the image before displaying it in the ImageView but without respect to the image’s aspect ratio:

Resizing images in this way without respect to the original aspect ratio will often make the image appear skewed or distorted. In most cases, this should be avoided, and Glide offers two standard scaling transformation options to prevent this: centerCrop and fitCenter .

If you only want to resize one dimension, use Target.SIZE_ORIGINAL as a placeholder for the other dimension:

Calling centerCrop() scales the image so that it fills the requested bounds of the ImageView and then crops the extra. The ImageView will be filled completely, but the entire image might not be displayed.

Calling fitCenter() scales the image so that both dimensions are equal to or less than the requested bounds of the ImageView . The image will be displayed completely, but might not fill the entire ImageView .

If an image or set of images aren’t loading, make sure to check the Android monitor log in Android Studio. There’s a good chance you might see an java.lang.OutOfMemoryError «Failed to allocate a [. ] byte allocation with [. ] free bytes» or a Out of memory on a 51121168-byte allocation. . This is quite common and means that you are loading one or more large images that have not been properly resized.

First, you have to find which image(s) being loaded are likely causing this error. For any given Glide . call, we can fix this by one or more of the following approaches:

Add an explicit width or height to the ImageView by setting layout_width=500dp in the layout file.
Call .override(width, height) during the Glide load and explicitly set a width or height for the image such as: GlideApp.with(. ).load(imageUri).override(500, 500).into(. ) .
Try removing android:adjustViewBounds=»true» from your ImageView if present and if you not calling .override()
Open up your static placeholder or error images and make sure their dimensions are relatively small ( AndroidManifest.xml and then add android:largeHeap to your manifest:

Note that this is not generally a good idea, but can be used temporarily to trigger fewer out of memory errors.

If you experience errors loading images, you can create a RequestListener and pass it in via Glide.listener() to intercept errors:

Transformations are supported by an additional third-party library, glide-transformations. First, add the dependencies:

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Glide — Placeholders & Fade Animations

Moonshoot

Moonshoot is a
Student Feature.

After you’ve learned how to load images from all kinds of sources and how to display them in ListViews, this tutorial is all about placeholders, which bridge the time until the image loading.

Glide has released a 4.0.0 version. We’ve updated this tutorial accordingly. It is now for both versions, the previous release of Glide 3.8.0, and the newest 4.0.0 release 😍 Please keep in mind that the code snippets are different for each version.

Glide Series Overview

Upgrade Guide from Glide 3.x

Request Options & Generated API

Extending the Generated API

Getting Started
Advanced Loading
Upgrade Guide from Glide 3.x
Request Options & Generated API
Extending the Generated API

ListAdapter (ListView, GridView)

Placeholders & Fade Animations

Image Resizing & Scaling

Displaying Gifs & Video Thumbnails

Advanced ListViews With Images

Image Loading for RecyclerView and CardView

ListAdapter (ListView, GridView) Placeholders & Fade Animations
Image Resizing & Scaling
Displaying Gifs & Video Thumbnails
Thumbnails
Advanced ListViews With Images
Image Loading for RecyclerView and CardView

How to Choose the Best Caching Preference

How to Ignore URL Query Parameters In Cache Lookup

Callbacks: SimpleTarget and ViewTarget for Custom View Classes

Loading Images into Notifications and AppWidgets

Custom Animations with animate()

How to Rotate Images

Integrating Networking Stacks

Customize Glide with Modules

Glide Module Example: Accepting Self-Signed HTTPS Certificates

Glide Module Example: Customize Caching

Glide Module Example: Optimizing By Loading Images In Custom Sizes

Dynamically Use Model Loaders

Exceptions: Debugging and Error Handling

App Release Preparation

Network-Dependent Image Loading

Analyzing Image Loading with Android Studio Profiler

Log Image Loading with Stetho and Chrome Developer Tools

Customize Network Timeouts

Exceptions: Debugging and Error Handling
Series Roundup
App Release Preparation
Network-Dependent Image Loading
Analyzing Image Loading with Android Studio Profiler
Log Image Loading with Stetho and Chrome Developer Tools
Customize Network Timeouts

Placeholders with .placeholder()

We probably don’t even have to explain or discuss it: empty ImageView s don’t look good in any UI. If you’re using Glide, you most likely are loading images via an Internet connection. Depending on your user’s environment, this might take a significant amount of time. An expected behavior of an app is to display a placeholder until the image is loaded and processed.

Glide’s fluent interface makes this very easy to do! Just call .placeHolder() with a reference to a drawable (resource) and Glide will display that as a placeholder until your actual image is ready. Keep in mind that this process is done on the UI-thread. Thus, don’t use giant images for the placeholder. Instead, use smaller images which are fast to load as placeholders:

Glide 4.x

Glide 3.x

For obvious reasons, you cannot set an Internet url as placeholder, since that one would be required to be loaded as well. App resources and drawables are guaranteed to be available, accessible and relatively efficient. However, as the parameter of the load() method, Glide accepts all kind of values. These might not be loadable (no Internet connection, server down, . ), deleted or not accessible. In the next section, we’ll talk about an error placeholder.

Error Placeholder with .error()

Let’s assume our app tries to load an image from a website, which is currently down. Glide does give us the option to get an error callback and take the appropriate action. While we’ll cover that option later, for now this would be too complicated. In most use cases a placeholder, which signals that the image could not be loaded is sufficient enough.

The call to Glide’s fluent interface is identical to the previous example for our pre-display placeholder, just with a different function call named error() :

Glide 4.x

Glide 3.x

That’s it. If the image you define as load() value cannot be loaded, Glide will display R.mipmap.future_studio_launcher instead. Once again, acceptable parameters for error() are only already initialized drawable objects or pointers to their resources ( R.drawable. ).

Dynamic Error Placeholder

Starting with Glide 4.3.0 you can also pass a full Glide request to the error() method. That means you don’t have to provide an error placeholder with the phone. Instead, you could load any other image from the Internet.

For example, your app might try to load a profile image of a user. If the request doesn’t work out, you can try a backup image from a different URL, instead of just serving a generic placeholder. The code is straightforward:

You pass a full Glide request to the error() method. The passed Glide request has all options available, so you could also add transformations, animations, etc.

.fallback() Placeholder

The .error() placeholder is triggered when the resource is not available, for example the image link is down. Another type of “error” is if you pass a null value to Glide. For example, this could happen if you’ve a ListView with profile images. Not every profile has an image set and thus you’re passing a null value. If you want to specify a good replacement image when you pass null , use .fallback() :

Glide 4.x

Glide 3.x

The rules are identical to .placeholder() : you can only pass a drawable or a resource id.

Transitions

No matter if you’re displaying a placeholder before loading the image or not, changing an image of an ImageView is a pretty significant change in your UI. A simple option to make this change more smoothly and easier on the eye, is to use a crossfade animation. Glide ships with a standard crossfade animation, which is active by default for Glide 3.6.1 until Glide 3.8.0. If you want to force Glide to show the crossfade animation, all you’ve to do is another call on the builder:

Glide 4.x

Glide 3.x

The withCrossFade , or crossFade() methods have another method signature: (int duration) . If you want to slow down (or speed up) the animation, feel free to pass a time in milliseconds to the methods. The default duration of the transition is 300 milliseconds.

Glide 3.x: Use of dontAnimate()

If you’re using Glide 3.x and wish to directly display the image without the small crossfade effect, call .dontAnimate() on the Glide request builder:

This would directly show you the image, without fading it into the ImageView . Please make sure you’ve a good reason for doing this though!

Combining Everything

It is important to know that all these parameters are independent and can be set without relying on each other. For example, you could just set .error() without calling .placeholder() . You could set the crossfade animations without the placeholders. Any combination of the parameters is possible.

Outlook

Hopefully you learned a lot from this tutorial. It is tremendously important for a good user experience that the images are not popping in unexpectedly. Also, make it obvious to the user when something goes wrong. Glide assists you with easy-to-call functions, which provide the things you need to design a better app.

Don’t forget to check out the official documentation, which also covers placeholders and transitions.

In the context of this tutorial series, we’re not done with the optimization options yet. In the next tutorial, we’ll look at image resizing and scaling.

Still Have Questions? Get Our Glide Book!

In order to be competitive in today’s Google Play environment, your app needs to be polished. Images need to be used consistently and loaded smoothly.

Learn how to create and completely customize image-rich Android apps with our book on Glide. Save yourself valuable development time by learning Glide’s functionality for an amazing user experience directly from us.

Boost your productivity and enjoy working with images on Android.

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Placeholder glide android studio