com.bumptech.glide.request

Class RequestFutureTarget<R>

java.lang.Object

com.bumptech.glide.request.RequestFutureTarget<R>

Type Parameters:

R - The type of the resource that will be loaded.

All Implemented Interfaces:

LifecycleListener, FutureTarget<R>, RequestListener<R>, Target<R>, java.util.concurrent.Future<R>

public class RequestFutureTarget<R>
extends java.lang.Object
implements FutureTarget<R>, RequestListener<R>

A Future implementation for Glide that can be used to load resources in a blocking manner on background threads.

Note - Unlike most targets, RequestFutureTargets can be used once and only once. Attempting to reuse a RequestFutureTarget will probably result in undesirable behavior or exceptions. Instead of reusing objects of this class, the pattern should be:

 FutureTarget<File> target = null;
 RequestManager requestManager = Glide.with(context);
 try {
   target = requestManager
      .downloadOnly()
      .load(model)
      .submit();
   File downloadedFile = target.get();
   // ... do something with the file (usually throws IOException)
 } catch (ExecutionException | InterruptedException | IOException e) {
   // ... bug reporting or recovery
 } finally {
   // make sure to cancel pending operations and free resources
   if (target != null) {
     target.cancel(true); // mayInterruptIfRunning
   }
 }
 

The cancel(boolean) call will cancel pending operations and make sure that any resources used are recycled.

Field Summary

Fields inherited from interface com.bumptech.glide.request.target.Target

SIZE_ORIGINAL

Constructor Summary

Constructors

Constructor and Description
RequestFutureTarget(int width, int height) Constructor for a RequestFutureTarget.

Method Summary

Modifier and Type	Method and Description
boolean	cancel(boolean mayInterruptIfRunning)
R	get()
R	get(long time, java.util.concurrent.TimeUnit timeUnit)
Request	getRequest() Retrieves the current request for this target, should not be called outside of Glide.
void	getSize(SizeReadyCallback cb) A callback that should never be invoked directly.
boolean	isCancelled()
boolean	isDone()
void	onDestroy() Callback for when Fragment.onDestroy()} or Activity.onDestroy() is called.
void	onLoadCleared(android.graphics.drawable.Drawable placeholder) A callback that should never be invoked directly.
void	onLoadFailed(android.graphics.drawable.Drawable errorDrawable) A callback that should never be invoked directly.
boolean	onLoadFailed(GlideException e, java.lang.Object model, Target<R> target, boolean isFirstResource) Called when an exception occurs during a load, immediately before Target.onLoadFailed(Drawable).
void	onLoadStarted(android.graphics.drawable.Drawable placeholder) A callback that should never be invoked directly.
boolean	onResourceReady(R resource, java.lang.Object model, Target<R> target, DataSource dataSource, boolean isFirstResource) Called when a load completes successfully, immediately before Target.onResourceReady(Object, com.bumptech.glide.request.transition.Transition).
void	onResourceReady(R resource, Transition<? super R> transition) A callback that should never be invoked directly.
void	onStart() Callback for when Fragment.onStart()} or Activity.onStart() is called.
void	onStop() Callback for when Fragment.onStop()} or Activity.onStop()} is called.
void	removeCallback(SizeReadyCallback cb) Removes the given callback from the pending set if it's still retained.
void	setRequest(Request request) Sets the current request for this target to retain, should not be called outside of Glide.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RequestFutureTarget

public RequestFutureTarget(int width,
                           int height)

Constructor for a RequestFutureTarget. Should not be used directly.

Method Detail

cancel

public boolean cancel(boolean mayInterruptIfRunning)

Specified by:

cancel in interface java.util.concurrent.Future<R>

isCancelled

public boolean isCancelled()

Specified by:

isCancelled in interface java.util.concurrent.Future<R>

isDone

public boolean isDone()

Specified by:

isDone in interface java.util.concurrent.Future<R>

get

public R get()
      throws java.lang.InterruptedException,
             java.util.concurrent.ExecutionException

Specified by:

get in interface java.util.concurrent.Future<R>

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

get

public R get(long time,
             @NonNull
             java.util.concurrent.TimeUnit timeUnit)
      throws java.lang.InterruptedException,
             java.util.concurrent.ExecutionException,
             java.util.concurrent.TimeoutException

Specified by:

get in interface java.util.concurrent.Future<R>

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

java.util.concurrent.TimeoutException

getSize

public void getSize(@NonNull
                    SizeReadyCallback cb)

A callback that should never be invoked directly.

Specified by:

getSize in interface Target<R>

Parameters:

cb - The callback that must be called when the size of the target has been determined

removeCallback

public void removeCallback(@NonNull
                           SizeReadyCallback cb)

Description copied from interface: Target

Removes the given callback from the pending set if it's still retained.

Specified by:

removeCallback in interface Target<R>

Parameters:

cb - The callback to remove.

setRequest

public void setRequest(@Nullable
                       Request request)

Description copied from interface: Target

Sets the current request for this target to retain, should not be called outside of Glide.

Specified by:

setRequest in interface Target<R>

getRequest

@Nullable
public Request getRequest()

Description copied from interface: Target

Retrieves the current request for this target, should not be called outside of Glide.

Specified by:

getRequest in interface Target<R>

onLoadCleared

public void onLoadCleared(@Nullable
                          android.graphics.drawable.Drawable placeholder)

A callback that should never be invoked directly.

Specified by:

onLoadCleared in interface Target<R>

Parameters:

placeholder - The placeholder drawable to optionally show, or null.

onLoadStarted

public void onLoadStarted(@Nullable
                          android.graphics.drawable.Drawable placeholder)

A callback that should never be invoked directly.

Specified by:

onLoadStarted in interface Target<R>

Parameters:

placeholder - The placeholder drawable to optionally show, or null.

onLoadFailed

public void onLoadFailed(@Nullable
                         android.graphics.drawable.Drawable errorDrawable)

A callback that should never be invoked directly.

Specified by:

onLoadFailed in interface Target<R>

Parameters:

errorDrawable - The error drawable to optionally show, or null.

onResourceReady

public void onResourceReady(@NonNull
                            R resource,
                            @Nullable
                            Transition<? super R> transition)

A callback that should never be invoked directly.

Specified by:

onResourceReady in interface Target<R>

Parameters:

resource - the loaded resource.

onStart

public void onStart()

Description copied from interface: LifecycleListener

Callback for when Fragment.onStart()} or Activity.onStart() is called.

Specified by:

onStart in interface LifecycleListener

onStop

public void onStop()

Description copied from interface: LifecycleListener

Callback for when Fragment.onStop()} or Activity.onStop()} is called.

Specified by:

onStop in interface LifecycleListener

onDestroy

public void onDestroy()

Description copied from interface: LifecycleListener

Callback for when Fragment.onDestroy()} or Activity.onDestroy() is called.

Specified by:

onDestroy in interface LifecycleListener

onLoadFailed

public boolean onLoadFailed(@Nullable
                            GlideException e,
                            java.lang.Object model,
                            Target<R> target,
                            boolean isFirstResource)

Description copied from interface: RequestListener

Called when an exception occurs during a load, immediately before Target.onLoadFailed(Drawable). Will only be called if we currently want to display an image for the given model in the given target. It is recommended to create a single instance per activity/fragment rather than instantiate a new object for each call to Glide.with(fragment/activity).load() to avoid object churn.

It is not safe to reload this or a different model in this callback. If you need to do so use RequestBuilder.error(RequestBuilder) instead.

Although you can't start an entirely new load, it is safe to change what is displayed in the Target at this point, as long as you return true from the method to prevent Target.onLoadFailed(Drawable) from being called.

For threading guarantees, see the class comment.

For example:

 public boolean onLoadFailed(Exception e, T model, Target target, boolean isFirstResource) {
     target.setPlaceholder(R.drawable.a_specific_error_for_my_exception);
     return true; // Prevent onLoadFailed from being called on the Target.
 }
 

Specified by:

onLoadFailed in interface RequestListener<R>

Parameters:

e - The maybe null exception containing information about why the request failed.

model - The model we were trying to load when the exception occurred.

target - The Target we were trying to load the image into.

isFirstResource - true if this exception is for the first resource to load.

Returns:

true to prevent Target.onLoadFailed(Drawable) from being called on target, typically because the listener wants to update the target or the object the target wraps itself or false to allow Target.onLoadFailed(Drawable) to be called on target.

onResourceReady

public boolean onResourceReady(R resource,
                               java.lang.Object model,
                               Target<R> target,
                               DataSource dataSource,
                               boolean isFirstResource)

Description copied from interface: RequestListener

Called when a load completes successfully, immediately before Target.onResourceReady(Object, com.bumptech.glide.request.transition.Transition).

For threading guarantees, see the class comment.

Specified by:

onResourceReady in interface RequestListener<R>

Parameters:

resource - The resource that was loaded for the target.

model - The specific model that was used to load the image.

target - The target the model was loaded into.

dataSource - The DataSource the resource was loaded from.

isFirstResource - true if this is the first resource to in this load to be loaded into the target. For example when loading a thumbnail and a full-sized image, this will be true for the first image to load and false for the second.

Returns:

true to prevent Target.onLoadFailed(Drawable) from being called on target, typically because the listener wants to update the target or the object the target wraps itself or false to allow Target.onLoadFailed(Drawable) to be called on target.