RequestManager.java

/*
 * Created by Storm Zhang, Feb 11, 2014.
 */

package com.likebamboo.osa.android.request;

import android.app.ActivityManager;
import android.content.Context;

import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.ImageLoader;
import com.android.volley.toolbox.Volley;
import com.likebamboo.osa.android.cache.BitmapLruCache;

/**
 * volley请求管理
 */
public class RequestManager {
    private static RequestQueue mRequestQueue;
    private static ImageLoader mImageLoader;

    private RequestManager() {
        // no instances
    }

    /**
     * 初始化
     *
     * @param context
     */
    public static void init(Context context) {
        mRequestQueue = Volley.newRequestQueue(context);
        int memClass = ((ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE)).getMemoryClass();
        // Use 1/8th of the available memory for this memory cache.
        int cacheSize = 1024 * 1024 * memClass / 8;
        mImageLoader = new ImageLoader(mRequestQueue, new BitmapLruCache(cacheSize));
    }

    /**
     * 获取请求队列
     *
     * @return
     */
    public static RequestQueue getRequestQueue() {
        if (mRequestQueue != null) {
            return mRequestQueue;
        } else {
            throw new IllegalStateException("RequestQueue not initialized");
        }
    }

    /**
     * 添加请求
     *
     * @param request
     * @param tag
     */
    public static void addRequest(Request<?> request, Object... tag) {
        if (tag != null && tag.length > 0) {
            request.setTag(tag[0]);
        }
        mRequestQueue.add(request);
    }

    /**
     * 取消请求
     *
     * @param tag
     */
    public static void cancelAll(Object tag) {
        mRequestQueue.cancelAll(tag);
    }

    /**
     * Returns instance of ImageLoader initialized with {@see FakeImageCache}
     * which effectively means that no memory caching is used. This is useful
     * for images that you know that will be show only once.
     *
     * @return
     */
    public static ImageLoader getImageLoader() {
        if (mImageLoader != null) {
            return mImageLoader;
        } else {
            throw new IllegalStateException("ImageLoader not initialized");
        }
    }
}