Android NetworkImageView点击查看大图 自定义属性

 

package com.xxx

/**
 * Copyright (C) 2013 The Android Open Source Project
 *
 * 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.
 */

import android.app.Dialog;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.AdapterView;
import android.widget.ImageView;

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

/**
 * 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;

    private boolean isShowBigPhoto;

    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);
        //        isShowBigPhoto = attrs.getAttributeBooleanValue(
        //                R.styleable.NetworkImageView.isShowBigPhoto, false);
        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.NetworkImageView);
        isShowBigPhoto = ta.getBoolean(R.styleable.NetworkImageView_isShowBigPhoto, false);
        ta.recycle();
    }

    /**
     * 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);
        if (isShowBigPhoto) {
            this.setOnClickListener(onClickListener);
        }
    }

    @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();
    }

    private ShowBidPhotoDialog dialog;

    private View.OnClickListener onClickListener = new View.OnClickListener() {

        public boolean onLongClick(View v) {
            if (dialog == null) {
                dialog = new ShowBidPhotoDialog(NetworkImageView.this.getContext(),
                        ((BitmapDrawable) NetworkImageView.this.getDrawable()).getBitmap());
                dialog.show();
            }
            return false;
        }

        @Override
        public void onClick(View v) {
            onLongClick(v);
        }
    };

    class ShowBidPhotoDialog extends Dialog implements AdapterView.OnItemClickListener {

        private Bitmap bitmap;

        public ShowBidPhotoDialog(Context context, Bitmap catalogs) {
            super(context, R.style.CustomProgressDialog);
            this.setCanceledOnTouchOutside(true);
            bitmap = catalogs;
        }

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            this.setContentView(R.layout.big_photo_dialog);
            ImageView bigImg = (ImageView) this.findViewById(R.id.imageBig);
            bigImg.setImageBitmap(bitmap);
            //            bitmap.recycle();
        }

        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            this.hide();
        }
    }
}

注意layout中自定义属性获取：

TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.NetworkImageView);
        isShowBigPhoto = ta.getBoolean(R.styleable.NetworkImageView_isShowBigPhoto, false);
        ta.recycle();

 

 

在value/attrs.xml中定义属性

<resources>
      <declare-styleable name="NetworkImageView">
        <attr name="isShowBigPhoto" format="boolean" />
    </declare-styleable>
</resources>

 

在layout中使用：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:myViewXmlns="http://schemas.android.com/apk/res/com.xxx"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/parents_bg" >
<com.xxx.NetworkImageView
            android:id="@+id/draw_image"
            android:layout_width="267dp"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:paddingTop="20dp"
            android:scaleType="fitCenter"
            myViewXmlns:isShowBigPhoto="true" />
</RelativeLayout>

 

参考：http://www.cnblogs.com/trinea/archive/2012/11/14/2768271.html