import com.lidroid.xutils.bitmap.callback.BitmapLoadCallBack; //导入依赖的package包/类
@SuppressWarnings("unchecked")
private static <T extends View> BitmapLoadTask<T> getBitmapTaskFromContainer(T container, BitmapLoadCallBack<T> callBack) {
    if (container != null) {
        final Drawable drawable = callBack.getDrawable(container);
        if (drawable instanceof AsyncDrawable) {
            final AsyncDrawable<T> asyncDrawable = (AsyncDrawable<T>) drawable;
            return asyncDrawable.getBitmapWorkerTask();
        }
    }
    return null;
}
 

import com.lidroid.xutils.bitmap.callback.BitmapLoadCallBack; //导入依赖的package包/类
private static <T extends View> boolean bitmapLoadTaskExist(T container, String uri, BitmapLoadCallBack<T> callBack) {
	//这里的判断个人感觉可以优化， 其实如果uri一样， 其实就可以视作为任务存在。
    final BitmapLoadTask<T> oldLoadTask = getBitmapTaskFromContainer(container, callBack);

    if (oldLoadTask != null) {  
        final String oldUrl = oldLoadTask.uri;
        if (TextUtils.isEmpty(oldUrl) || !oldUrl.equals(uri)) {
            oldLoadTask.cancel(true);
        } else {
            return true;
        }
    }
    return false;
}
 

import com.lidroid.xutils.bitmap.callback.BitmapLoadCallBack; //导入依赖的package包/类
public BitmapLoadTask(T container, String uri, BitmapDisplayConfig config, BitmapLoadCallBack<T> callBack) {
    if (container == null || uri == null || config == null || callBack == null) {
        throw new IllegalArgumentException("args may not be null");
    }

    this.containerReference = new WeakReference<T>(container);
    this.callBack = callBack;
    this.uri = uri;
    this.displayConfig = config;
}
 

import com.lidroid.xutils.bitmap.callback.BitmapLoadCallBack; //导入依赖的package包/类
private static <T extends View> boolean bitmapLoadTaskExist(T container, String uri, BitmapLoadCallBack<T> callBack) {
    final BitmapLoadTask<T> oldLoadTask = getBitmapTaskFromContainer(container, callBack);

    if (oldLoadTask != null) {
        final String oldUrl = oldLoadTask.uri;
        if (TextUtils.isEmpty(oldUrl) || !oldUrl.equals(uri)) {
            oldLoadTask.cancel(true);
        } else {
            return true;
        }
    }
    return false;
}
 

import com.lidroid.xutils.bitmap.callback.BitmapLoadCallBack; //导入依赖的package包/类
public <T extends View> void display(T container, String uri, BitmapLoadCallBack<T> callBack) {
    display(container, uri, null, callBack);
}
 

import com.lidroid.xutils.bitmap.callback.BitmapLoadCallBack; //导入依赖的package包/类
/**
 * 加载图片
 * @param container
 * @param uri
 * @param callBack
 */
public static void display(ImageView container, String uri, BitmapLoadCallBack<ImageView> callBack) {
	mBitmapUtils.display(container, uri, callBack);
}