如何使用Picasso下载，保存和加载图像

Question

我知道Picasso可以自动下载和缓存图片，但是如果我重新启动手机，而且我没有上网，我该如何访问相同的图片？

这是我的实施

// Picasso doesn't process URIs as strings, but as files
if(songObject.albumArtURI != null){
    File f = new File(songObject.albumArtURI);

    Picasso.with(viewHolder.albumArt.getContext())
            .load(f)
            .transform(new CircleTransform())
            .placeholder(R.drawable.blackcircle)
            .into(viewHolder.albumArt);

// If songObject doesn't have URI but it has a URL do this     
} else if(songObject.albumURL != null){

    Picasso.with(viewHolder.albumArt.getContext())
            .load(songObject.albumURL)
            .transform(new CircleTransform())
            .placeholder(R.drawable.blackcircle)
            .into(viewHolder.albumArt);

// Otherwise download the URL    
} else {

    String JSONURL = "https://itunes.apple.com/search?term=michael+jackson";

    getRequestQueue();

    GsonRequest<SongInfo> myReq = new GsonRequest<SongInfo>(
            Request.Method.GET,
            JSONURL,
            SongInfo.class,
            null,
            createMyReqSuccessListener(songObject),
            createMyReqErrorListener());

    mRequestQueue.add(myReq);

    Picasso.with(viewHolder.albumArt.getContext())
            .load(R.drawable.blackcircle)
            .transform(new CircleTransform())
            .placeholder(R.drawable.blackcircle)
            .into(viewHolder.albumArt);
}