Android Open Source - SimpleJsonAdapter Network Image View






From Project

Back to project page SimpleJsonAdapter.

License

The source code is released under:

Apache License

If you think the Android project SimpleJsonAdapter listed in this page is inappropriate, such as containing malicious code/tools or violating the copyright, please email info at java2s dot com, thanks.

Java Source Code

/**
 * Copyright (C) 2013 The Android Open Source Project
 *//from  w  ww. j  av a  2  s .  com
 * 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.
 */
package com.android.volley.toolbox;

import android.content.Context;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.ViewGroup.LayoutParams;
import android.widget.ImageView;

import com.android.volley.VolleyError;
import com.android.volley.toolbox.ImageLoader.ImageContainer;
import com.android.volley.toolbox.ImageLoader.ImageListener;

/**
 * Handles fetching an image from a URL as well as the life-cycle of the
 * associated request.
 */
public class NetworkImageView extends ImageView {
    /** The URL of the network image to load */
    private String mUrl;

    /**
     * Resource ID of the image to be used as a placeholder until the network image is loaded.
     */
    private int mDefaultImageId;

    /**
     * Resource ID of the image to be used if the network response fails.
     */
    private int mErrorImageId;

    /** Local copy of the ImageLoader. */
    private ImageLoader mImageLoader;

    /** Current ImageContainer. (either in-flight or finished) */
    private ImageContainer mImageContainer;

    public NetworkImageView(Context context) {
        this(context, null);
    }

    public NetworkImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public NetworkImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    /**
     * Sets URL of the image that should be loaded into this view. Note that calling this will
     * immediately either set the cached image (if available) or the default image specified by
     * {@link NetworkImageView#setDefaultImageResId(int)} on the view.
     *
     * NOTE: If applicable, {@link NetworkImageView#setDefaultImageResId(int)} and
     * {@link NetworkImageView#setErrorImageResId(int)} should be called prior to calling
     * this function.
     *
     * @param url The URL that should be loaded into this ImageView.
     * @param imageLoader ImageLoader that will be used to make the request.
     */
    public void setImageUrl(String url, ImageLoader imageLoader) {
        mUrl = url;
        mImageLoader = imageLoader;
        // The URL has potentially changed. See if we need to load it.
        loadImageIfNecessary(false);
    }

    /**
     * Sets the default image resource ID to be used for this view until the attempt to load it
     * completes.
     */
    public void setDefaultImageResId(int defaultImage) {
        mDefaultImageId = defaultImage;
    }

    /**
     * Sets the error image resource ID to be used for this view in the event that the image
     * requested fails to load.
     */
    public void setErrorImageResId(int errorImage) {
        mErrorImageId = errorImage;
    }

    /**
     * Loads the image for the view if it isn't already loaded.
     * @param isInLayoutPass True if this was invoked from a layout pass, false otherwise.
     */
    void loadImageIfNecessary(final boolean isInLayoutPass) {
        int width = getWidth();
        int height = getHeight();

        boolean wrapWidth = false, wrapHeight = false;
        if (getLayoutParams() != null) {
            wrapWidth = getLayoutParams().width == LayoutParams.WRAP_CONTENT;
            wrapHeight = getLayoutParams().height == LayoutParams.WRAP_CONTENT;
        }

        // if the view's bounds aren't known yet, and this is not a wrap-content/wrap-content
        // view, hold off on loading the image.
        boolean isFullyWrapContent = wrapWidth && wrapHeight;
        if (width == 0 && height == 0 && !isFullyWrapContent) {
            return;
        }

        // if the URL to be loaded in this view is empty, cancel any old requests and clear the
        // currently loaded image.
        if (TextUtils.isEmpty(mUrl)) {
            if (mImageContainer != null) {
                mImageContainer.cancelRequest();
                mImageContainer = null;
            }
            setDefaultImageOrNull();
            return;
        }

        // if there was an old request in this view, check if it needs to be canceled.
        if (mImageContainer != null && mImageContainer.getRequestUrl() != null) {
            if (mImageContainer.getRequestUrl().equals(mUrl)) {
                // if the request is from the same URL, return.
                return;
            } else {
                // if there is a pre-existing request, cancel it if it's fetching a different URL.
                mImageContainer.cancelRequest();
                setDefaultImageOrNull();
            }
        }

        // Calculate the max image width / height to use while ignoring WRAP_CONTENT dimens.
        int maxWidth = wrapWidth ? 0 : width;
        int maxHeight = wrapHeight ? 0 : height;

        // The pre-existing content of this view didn't match the current URL. Load the new image
        // from the network.
        ImageContainer newContainer = mImageLoader.get(mUrl,
                new ImageListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        if (mErrorImageId != 0) {
                            setImageResource(mErrorImageId);
                        }
                    }

                    @Override
                    public void onResponse(final ImageContainer response, boolean isImmediate) {
                        // If this was an immediate response that was delivered inside of a layout
                        // pass do not set the image immediately as it will trigger a requestLayout
                        // inside of a layout. Instead, defer setting the image by posting back to
                        // the main thread.
                        if (isImmediate && isInLayoutPass) {
                            post(new Runnable() {
                                @Override
                                public void run() {
                                    onResponse(response, false);
                                }
                            });
                            return;
                        }

                        if (response.getBitmap() != null) {
                            setImageBitmap(response.getBitmap());
                        } else if (mDefaultImageId != 0) {
                            setImageResource(mDefaultImageId);
                        }
                    }
                }, maxWidth, maxHeight);

        // update the ImageContainer to be the new bitmap container.
        mImageContainer = newContainer;
    }

    private void setDefaultImageOrNull() {
        if(mDefaultImageId != 0) {
            setImageResource(mDefaultImageId);
        }
        else {
            setImageBitmap(null);
        }
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        loadImageIfNecessary(true);
    }

    @Override
    protected void onDetachedFromWindow() {
        if (mImageContainer != null) {
            // If the view was bound to an image request, cancel it and clear
            // out the image from the view.
            mImageContainer.cancelRequest();
            setImageBitmap(null);
            // also clear out the container so we can reload the image if necessary.
            mImageContainer = null;
        }
        super.onDetachedFromWindow();
    }

    @Override
    protected void drawableStateChanged() {
        super.drawableStateChanged();
        invalidate();
    }
}




Java Source Code List

com.android.volley.AuthFailureError.java
com.android.volley.CacheDispatcher.java
com.android.volley.Cache.java
com.android.volley.DefaultRetryPolicy.java
com.android.volley.ExecutorDelivery.java
com.android.volley.NetworkDispatcher.java
com.android.volley.NetworkError.java
com.android.volley.NetworkResponse.java
com.android.volley.Network.java
com.android.volley.NoConnectionError.java
com.android.volley.ParseError.java
com.android.volley.RequestQueue.java
com.android.volley.RequestTest.java
com.android.volley.Request.java
com.android.volley.ResponseDelivery.java
com.android.volley.Response.java
com.android.volley.RetryPolicy.java
com.android.volley.ServerError.java
com.android.volley.TimeoutError.java
com.android.volley.VolleyError.java
com.android.volley.VolleyLog.java
com.android.volley.mock.MockCache.java
com.android.volley.mock.MockHttpClient.java
com.android.volley.mock.MockHttpStack.java
com.android.volley.mock.MockHttpURLConnection.java
com.android.volley.mock.MockNetwork.java
com.android.volley.mock.MockRequest.java
com.android.volley.mock.MockResponseDelivery.java
com.android.volley.mock.TestRequest.java
com.android.volley.mock.WaitableQueue.java
com.android.volley.toolbox.AndroidAuthenticator.java
com.android.volley.toolbox.Authenticator.java
com.android.volley.toolbox.BasicNetwork.java
com.android.volley.toolbox.ByteArrayPool.java
com.android.volley.toolbox.ClearCacheRequest.java
com.android.volley.toolbox.DiskBasedCache.java
com.android.volley.toolbox.HttpClientStack.java
com.android.volley.toolbox.HttpHeaderParser.java
com.android.volley.toolbox.HttpStack.java
com.android.volley.toolbox.HurlStack.java
com.android.volley.toolbox.ImageLoader.java
com.android.volley.toolbox.ImageRequest.java
com.android.volley.toolbox.JsonArrayRequest.java
com.android.volley.toolbox.JsonObjectRequest.java
com.android.volley.toolbox.JsonRequest.java
com.android.volley.toolbox.NetworkImageView.java
com.android.volley.toolbox.NoCache.java
com.android.volley.toolbox.PoolingByteArrayOutputStream.java
com.android.volley.toolbox.RequestFuture.java
com.android.volley.toolbox.StringRequest.java
com.android.volley.toolbox.Volley.java
com.android.volley.utils.CacheTestUtils.java
com.android.volley.utils.ImmediateResponseDelivery.java
os.ransj.adapter.SimpleJsonAdapter.java
os.ransj.demo.AdvanceJsonAdapterDemo.java
os.ransj.demo.MainEntry.java
os.ransj.demo.SimpleJsonAdapterDemo.java