com.android.volley.toolbox

Class ImageRequest

java.lang.Object

com.android.volley.Request<android.graphics.Bitmap>

com.android.volley.toolbox.ImageRequest

All Implemented Interfaces:

java.lang.Comparable<Request<android.graphics.Bitmap>>

public class ImageRequest
extends Request<android.graphics.Bitmap>

A canned request for getting an image at a given URL and calling back with a decoded Bitmap.

Nested Class Summary

Nested classes/interfaces inherited from class com.android.volley.Request

Request.Method, Request.Priority

Field Summary

Fields

Modifier and Type	Field and Description
static float	DEFAULT_IMAGE_BACKOFF_MULT Default backoff multiplier for image requests
static int	DEFAULT_IMAGE_MAX_RETRIES Default number of retries for image requests
static int	DEFAULT_IMAGE_TIMEOUT_MS Socket timeout in milliseconds for image requests

Constructor Summary

Constructors

Constructor and Description
ImageRequest(java.lang.String url, Response.Listener<android.graphics.Bitmap> listener, int maxWidth, int maxHeight, android.graphics.Bitmap.Config decodeConfig, Response.ErrorListener errorListener) Deprecated.
ImageRequest(java.lang.String url, Response.Listener<android.graphics.Bitmap> listener, int maxWidth, int maxHeight, android.widget.ImageView.ScaleType scaleType, android.graphics.Bitmap.Config decodeConfig, Response.ErrorListener errorListener) Creates a new image request, decoding to a maximum specified width and height.

Method Summary

Modifier and Type	Method and Description
void	cancel() Mark this request as canceled.
protected void	deliverResponse(android.graphics.Bitmap response) Subclasses must implement this to perform delivery of the parsed response to their listeners.
Request.Priority	getPriority() Returns the Request.Priority of this request; Request.Priority.NORMAL by default.
protected Response<android.graphics.Bitmap>	parseNetworkResponse(NetworkResponse response) Subclasses must implement this to parse the raw network response and return an appropriate response type.

Methods inherited from class com.android.volley.Request

addMarker, compareTo, deliverError, getBody, getBodyContentType, getCacheEntry, getCacheKey, getErrorListener, getHeaders, getMethod, getParams, getParamsEncoding, getPostBody, getPostBodyContentType, getPostParams, getPostParamsEncoding, getRetryPolicy, getSequence, getTag, getTimeoutMs, getTrafficStatsTag, getUrl, hasHadResponseDelivered, isCanceled, markDelivered, parseNetworkError, setCacheEntry, setRequestQueue, setRetryPolicy, setSequence, setShouldCache, setShouldRetryServerErrors, setTag, shouldCache, shouldRetryServerErrors, toString

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_IMAGE_TIMEOUT_MS

public static final int DEFAULT_IMAGE_TIMEOUT_MS

Socket timeout in milliseconds for image requests

See Also:

Constant Field Values

DEFAULT_IMAGE_MAX_RETRIES

public static final int DEFAULT_IMAGE_MAX_RETRIES

Default number of retries for image requests

See Also:

Constant Field Values

DEFAULT_IMAGE_BACKOFF_MULT

public static final float DEFAULT_IMAGE_BACKOFF_MULT

Default backoff multiplier for image requests

See Also:

Constant Field Values

Constructor Detail

ImageRequest

public ImageRequest(java.lang.String url,
                    Response.Listener<android.graphics.Bitmap> listener,
                    int maxWidth,
                    int maxHeight,
                    android.widget.ImageView.ScaleType scaleType,
                    android.graphics.Bitmap.Config decodeConfig,
                    Response.ErrorListener errorListener)

Creates a new image request, decoding to a maximum specified width and height. If both width and height are zero, the image will be decoded to its natural size. If one of the two is nonzero, that dimension will be clamped and the other one will be set to preserve the image's aspect ratio. If both width and height are nonzero, the image will be decoded to be fit in the rectangle of dimensions width x height while keeping its aspect ratio.

Parameters:

url - URL of the image

listener - Listener to receive the decoded bitmap

maxWidth - Maximum width to decode this bitmap to, or zero for none

maxHeight - Maximum height to decode this bitmap to, or zero for none

scaleType - The ImageViews ScaleType used to calculate the needed image size.

decodeConfig - Format to decode the bitmap to

errorListener - Error listener, or null to ignore errors

ImageRequest

@Deprecated
public ImageRequest(java.lang.String url,
                                Response.Listener<android.graphics.Bitmap> listener,
                                int maxWidth,
                                int maxHeight,
                                android.graphics.Bitmap.Config decodeConfig,
                                Response.ErrorListener errorListener)

Deprecated.

For API compatibility with the pre-ScaleType variant of the constructor. Equivalent to the normal constructor with ScaleType.CENTER_INSIDE.

Method Detail

getPriority

public Request.Priority getPriority()

Description copied from class: Request

Returns the Request.Priority of this request; Request.Priority.NORMAL by default.

Overrides:

getPriority in class Request<android.graphics.Bitmap>

parseNetworkResponse

protected Response<android.graphics.Bitmap> parseNetworkResponse(NetworkResponse response)

Description copied from class: Request

Subclasses must implement this to parse the raw network response and return an appropriate response type. This method will be called from a worker thread. The response will not be delivered if you return null.

Specified by:

parseNetworkResponse in class Request<android.graphics.Bitmap>

Parameters:

response - Response from the network

Returns:

The parsed response, or null in the case of an error

cancel

public void cancel()

Description copied from class: Request

Mark this request as canceled.

No callback will be delivered as long as either:

• This method is called on the same thread as the ResponseDelivery is running on. By default, this is the main thread.
• The request subclass being used overrides cancel() and ensures that it does not invoke the listener in Request.deliverResponse(T) after cancel() has been called in a thread-safe manner.

There are no guarantees if both of these conditions aren't met.

Overrides:

cancel in class Request<android.graphics.Bitmap>

deliverResponse

protected void deliverResponse(android.graphics.Bitmap response)

Description copied from class: Request

Subclasses must implement this to perform delivery of the parsed response to their listeners. The given response is guaranteed to be non-null; responses that fail to parse are not delivered.

Specified by:

deliverResponse in class Request<android.graphics.Bitmap>

Parameters:

response - The parsed response returned by Request.parseNetworkResponse(NetworkResponse)