Android uses the volley framework to load a large number of images in the ListView

The entries in the 1.listview are to be used with the Networkimageview in volley, but if you use ImageView directly, you can use the tag tag with the URL address set to ImageView in the GetView method

<?XML version= "1.0" encoding= "Utf-8"?><LinearLayoutxmlns:android= "Http://schemas.android.com/apk/res/android"Android:layout_width= "Match_parent"Android:layout_height= "Match_parent"android:orientation= "vertical" >    <Com.android.volley.toolbox.NetworkImageViewAndroid:id= "@+id/userimage"Android:layout_width= "100DP"Android:layout_height= "100DP" /></LinearLayout>

2. New picture Cache class Bitmapcache

ImportAndroid.graphics.Bitmap;ImportAndroid.support.v4.util.LruCache;ImportCom.android.volley.toolbox.ImageLoader.ImageCache; Public classBitmapcacheImplementsImagecache {PrivateLrucache<string, bitmap>Mcache;  PublicBitmapcache () {intMaxSize = 4 * 1024 * 1024; Mcache=NewLrucache<string, bitmap>(maxSize) {@Overrideprotected intsizeOf (String key, Bitmap Bitmap) {//return Bitmap.getbytecount ();//>api12 can use it.                returnBitmap.getrowbytes () *bitmap.getheight ();    }        }; } @Override PublicBitmap getbitmap (String url) {returnmcache.get (URL); } @Override Public voidputbitmap (String URL, Bitmap Bitmap) {if(Bitmap! =NULL) {mcache.put (URL, bitmap); }    }}

3.adapater Code

ImportAndroid.content.Context;ImportAndroid.view.LayoutInflater;ImportAndroid.view.View;ImportAndroid.view.ViewGroup;ImportAndroid.widget.BaseAdapter;ImportCom.android.volley.RequestQueue;ImportCom.android.volley.toolbox.ImageLoader;ImportCom.android.volley.toolbox.NetworkImageView;ImportCom.android.volley.toolbox.Volley; Public classMyadapterextendsBaseadapter {Privatestring[] list; Privatecontext Context; Privaterequestqueue queue; PrivateImageloader Imageloader;  PublicMyadapter (context context, string[] list) { This. Context =context;  This. List =list; Queue=volley.newrequestqueue (context); Imageloader=NewImageloader (Queue,NewBitmapcache ()); } @Override Public intGetCount () {returnlist.length; } @Override PublicObject GetItem (intposition) {        returnList[position]; } @Override Public LongGetitemid (intposition) {        returnposition; } @Override PublicView GetView (intposition, View Convertview, ViewGroup parent) {Viewholder Holder=NULL; if(Convertview = =NULL) {Holder=NewViewholder (); Convertview= Layoutinflater.from (context). Inflate (R.layout.list_item,NULL); Holder.img=(Networkimageview) Convertview.findviewbyid (r.id.userimage);        Convertview.settag (holder); } Else{Holder=(Viewholder) Convertview.gettag (); }        FinalString Imgurl =List[position]; if(Imgurl! =NULL&&!imgurl.equals ("") {holder.img.setDefaultImageResId (r.drawable.ic_launcher);            Holder.img.setErrorImageResId (R.drawable.ic_launcher);        HOLDER.IMG.SETIMAGEURL (Imgurl, Imageloader); }        returnConvertview; }    classviewholder {networkimageview img; }}

Android uses the volley framework to load a large number of images in the ListView