編輯:關於Android編程
MainActivity如下:
package cc.testlrucache; import android.os.Bundle; import android.widget.GridView; import android.app.Activity; /** * Demo描述: * 在GridView中采用LruCache異步加載大量圖片,避免OOM * * 學習資料: * http://blog.csdn.net/guolin_blog/article/details/9526203 * Thank you very much */ public class MainActivity extends Activity { private GridView mGridView; private GridViewAdapter mGridViewAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); init(); } private void init(){ mGridView = (GridView) findViewById(R.id.gridView); mGridViewAdapter = new GridViewAdapter(this, 0, ImagesUrl.Urls, mGridView); mGridView.setAdapter(mGridViewAdapter); } //取消所有的下載任務 @Override protected void onDestroy() { super.onDestroy(); mGridViewAdapter.cancelAllTasks(); } }
GridViewAdapter如下:
package cc.testlrucache; import java.net.HttpURLConnection; import java.net.URL; import java.util.HashSet; import android.annotation.SuppressLint; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.AsyncTask; import android.support.v4.util.LruCache; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.AbsListView; import android.widget.AbsListView.OnScrollListener; import android.widget.ArrayAdapter; import android.widget.GridView; import android.widget.ImageView; /** * LruCache的流程分析: * 我們從第一次進入應用的情況下開始 * 1 依據圖片的Url從LruCache緩存中取圖片. * 若圖片存在緩存中,則顯示該圖片;否則顯示默認圖片 * 2 因為是第一次進入該界面所以會執行: * loadBitmaps(firstVisibleItem, visibleItemCount); * 我們從loadBitmaps()方法作為切入點,繼續往下梳理 * 3 嘗試從LruCache緩存中取圖片.如果在顯示即可,否則進入4 * 4 開啟一個異步任務下載圖片.下載完成後顯示圖片,並且將 * 該圖片存入LruCache緩存中 * * 在停止滑動時,會調用loadBitmaps(firstVisibleItem, visibleItemCount) * 情況與上類似 */ @SuppressLint("NewApi") public class GridViewAdapter extends ArrayAdapter{ private GridView mGridView; //圖片緩存類 private LruCache mLruCache; //記錄所有正在下載或等待下載的任務 private HashSet mDownloadBitmapAsyncTaskHashSet; //GridView中可見的第一張圖片的下標 private int mFirstVisibleItem; //GridView中可見的圖片的數量 private int mVisibleItemCount; //記錄是否是第一次進入該界面 private boolean isFirstEnterThisActivity = true; public GridViewAdapter(Context context, int textViewResourceId,String[] objects, GridView gridView) { super(context, textViewResourceId, objects); mGridView = gridView; mGridView.setOnScrollListener(new ScrollListenerImpl()); mDownloadBitmapAsyncTaskHashSet = new HashSet (); // 獲取應用程序最大可用內存 int maxMemory = (int) Runtime.getRuntime().maxMemory(); // 設置圖片緩存大小為maxMemory的1/6 int cacheSize = maxMemory/6; mLruCache = new LruCache (cacheSize) { @Override protected int sizeOf(String key, Bitmap bitmap) { return bitmap.getByteCount(); } }; } @Override public View getView(int position, View convertView, ViewGroup parent) { String url = getItem(position); View view; if (convertView == null) { view = LayoutInflater.from(getContext()).inflate(R.layout.gridview_item, null); } else { view = convertView; } ImageView imageView = (ImageView) view.findViewById(R.id.imageView); //為該ImageView設置一個Tag,防止圖片錯位 imageView.setTag(url); //為該ImageView設置顯示的圖片 setImageForImageView(url, imageView); return view; } /** * 為ImageView設置圖片(Image) * 1 從緩存中獲取圖片 * 2 若圖片不在緩存中則為其設置默認圖片 */ private void setImageForImageView(String imageUrl, ImageView imageView) { Bitmap bitmap = getBitmapFromLruCache(imageUrl); if (bitmap != null) { imageView.setImageBitmap(bitmap); } else { imageView.setImageResource(R.drawable.default_image); } } /** * 將圖片存儲到LruCache */ public void addBitmapToLruCache(String key, Bitmap bitmap) { if (getBitmapFromLruCache(key) == null) { mLruCache.put(key, bitmap); } } /** * 從LruCache緩存獲取圖片 */ public Bitmap getBitmapFromLruCache(String key) { return mLruCache.get(key); } /** * 為GridView的item加載圖片 * * @param firstVisibleItem * GridView中可見的第一張圖片的下標 * * @param visibleItemCount * GridView中可見的圖片的數量 * */ private void loadBitmaps(int firstVisibleItem, int visibleItemCount) { try { for (int i = firstVisibleItem; i < firstVisibleItem + visibleItemCount; i++) { String imageUrl = ImagesUrl.Urls[i]; Bitmap bitmap = getBitmapFromLruCache(imageUrl); if (bitmap == null) { DownloadBitmapAsyncTask downloadBitmapAsyncTask = new DownloadBitmapAsyncTask(); mDownloadBitmapAsyncTaskHashSet.add(downloadBitmapAsyncTask); downloadBitmapAsyncTask.execute(imageUrl); } else { //依據Tag找到對應的ImageView顯示圖片 ImageView imageView = (ImageView) mGridView.findViewWithTag(imageUrl); if (imageView != null && bitmap != null) { imageView.setImageBitmap(bitmap); } } } } catch (Exception e) { e.printStackTrace(); } } /** * 取消所有正在下載或等待下載的任務 */ public void cancelAllTasks() { if (mDownloadBitmapAsyncTaskHashSet != null) { for (DownloadBitmapAsyncTask task : mDownloadBitmapAsyncTaskHashSet) { task.cancel(false); } } } private class ScrollListenerImpl implements OnScrollListener{ /** * * 我們的本意是通過onScrollStateChanged獲知:每次GridView停止滑動時加載圖片 * 但是存在一個特殊情況: * 當第一次入應用的時候,此時並沒有滑動屏幕的操作即不會調用onScrollStateChanged,但應該加載圖片. * 所以在此處做一個特殊的處理. * 即代碼: * if (isFirstEnterThisActivity && visibleItemCount > 0) { * loadBitmaps(firstVisibleItem, visibleItemCount); * isFirstEnterThisActivity = false; * } * * ------------------------------------------------------------ * * 其余的都是正常情況. * 所以我們需要不斷保存:firstVisibleItem和visibleItemCount * 從而便於中在onScrollStateChanged()判斷當停止滑動時加載圖片 * */ @Override public void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount) { mFirstVisibleItem = firstVisibleItem; mVisibleItemCount = visibleItemCount; if (isFirstEnterThisActivity && visibleItemCount > 0) { loadBitmaps(firstVisibleItem, visibleItemCount); isFirstEnterThisActivity = false; } } /** * GridView停止滑動時下載圖片 * 其余情況下取消所有正在下載或者等待下載的任務 */ @Override public void onScrollStateChanged(AbsListView view, int scrollState) { if (scrollState == SCROLL_STATE_IDLE) { loadBitmaps(mFirstVisibleItem, mVisibleItemCount); } else { cancelAllTasks(); } } } /** * 下載圖片的異步任務 */ class DownloadBitmapAsyncTask extends AsyncTask { private String imageUrl; @Override protected Bitmap doInBackground(String... params) { imageUrl = params[0]; Bitmap bitmap = downloadBitmap(params[0]); if (bitmap != null) { //下載完後,將其緩存到LrcCache addBitmapToLruCache(params[0], bitmap); } return bitmap; } @Override protected void onPostExecute(Bitmap bitmap) { super.onPostExecute(bitmap); //下載完成後,找到其對應的ImageView顯示圖片 ImageView imageView = (ImageView) mGridView.findViewWithTag(imageUrl); if (imageView != null && bitmap != null) { imageView.setImageBitmap(bitmap); } mDownloadBitmapAsyncTaskHashSet.remove(this); } } // 獲取Bitmap private Bitmap downloadBitmap(String imageUrl) { Bitmap bitmap = null; HttpURLConnection httpURLConnection = null; try { URL url = new URL(imageUrl); httpURLConnection = (HttpURLConnection) url.openConnection(); httpURLConnection.setConnectTimeout(5 * 1000); httpURLConnection.setReadTimeout(10 * 1000); httpURLConnection.setDoInput(true); httpURLConnection.setDoOutput(true); bitmap = BitmapFactory.decodeStream(httpURLConnection.getInputStream()); } catch (Exception e) { e.printStackTrace(); } finally { if (httpURLConnection != null) { httpURLConnection.disconnect(); } } return bitmap; } }
ImagesUrl如下:
package cc.testlrucache; public class ImagesUrl { public final static String[] Urls = new String[] { "https://lh6.googleusercontent.com/-55osAWw3x0Q/URquUtcFr5I/AAAAAAAAAbs/rWlj1RUKrYI/s160-c/A%252520Photographer.jpg", "https://lh4.googleusercontent.com/--dq8niRp7W4/URquVgmXvgI/AAAAAAAAAbs/-gnuLQfNnBA/s160-c/A%252520Song%252520of%252520Ice%252520and%252520Fire.jpg", "https://lh5.googleusercontent.com/-7qZeDtRKFKc/URquWZT1gOI/AAAAAAAAAbs/hqWgteyNXsg/s160-c/Another%252520Rockaway%252520Sunset.jpg", "https://lh3.googleusercontent.com/--L0Km39l5J8/URquXHGcdNI/AAAAAAAAAbs/3ZrSJNrSomQ/s160-c/Antelope%252520Butte.jpg", "https://lh6.googleusercontent.com/-8HO-4vIFnlw/URquZnsFgtI/AAAAAAAAAbs/WT8jViTF7vw/s160-c/Antelope%252520Hallway.jpg", "https://lh4.googleusercontent.com/-WIuWgVcU3Qw/URqubRVcj4I/AAAAAAAAAbs/YvbwgGjwdIQ/s160-c/Antelope%252520Walls.jpg", "https://lh6.googleusercontent.com/-UBmLbPELvoQ/URqucCdv0kI/AAAAAAAAAbs/IdNhr2VQoQs/s160-c/Apre%2525CC%252580s%252520la%252520Pluie.jpg", "https://lh3.googleusercontent.com/-s-AFpvgSeew/URquc6dF-JI/AAAAAAAAAbs/Mt3xNGRUd68/s160-c/Backlit%252520Cloud.jpg", "https://lh5.googleusercontent.com/-bvmif9a9YOQ/URquea3heHI/AAAAAAAAAbs/rcr6wyeQtAo/s160-c/Bee%252520and%252520Flower.jpg", "https://lh5.googleusercontent.com/-n7mdm7I7FGs/URqueT_BT-I/AAAAAAAAAbs/9MYmXlmpSAo/s160-c/Bonzai%252520Rock%252520Sunset.jpg", "https://lh6.googleusercontent.com/-4CN4X4t0M1k/URqufPozWzI/AAAAAAAAAbs/8wK41lg1KPs/s160-c/Caterpillar.jpg", "https://lh3.googleusercontent.com/-rrFnVC8xQEg/URqufdrLBaI/AAAAAAAAAbs/s69WYy_fl1E/s160-c/Chess.jpg", "https://lh5.googleusercontent.com/-WVpRptWH8Yw/URqugh-QmDI/AAAAAAAAAbs/E-MgBgtlUWU/s160-c/Chihuly.jpg", "https://lh5.googleusercontent.com/-0BDXkYmckbo/URquhKFW84I/AAAAAAAAAbs/ogQtHCTk2JQ/s160-c/Closed%252520Door.jpg", "https://lh3.googleusercontent.com/-PyggXXZRykM/URquh-kVvoI/AAAAAAAAAbs/hFtDwhtrHHQ/s160-c/Colorado%252520River%252520Sunset.jpg", "https://lh3.googleusercontent.com/-ZAs4dNZtALc/URquikvOCWI/AAAAAAAAAbs/DXz4h3dll1Y/s160-c/Colors%252520of%252520Autumn.jpg", "https://lh4.googleusercontent.com/-GztnWEIiMz8/URqukVCU7bI/AAAAAAAAAbs/jo2Hjv6MZ6M/s160-c/Countryside.jpg", "https://lh4.googleusercontent.com/-bEg9EZ9QoiM/URquklz3FGI/AAAAAAAAAbs/UUuv8Ac2BaE/s160-c/Death%252520Valley%252520-%252520Dunes.jpg", "https://lh6.googleusercontent.com/-ijQJ8W68tEE/URqulGkvFEI/AAAAAAAAAbs/zPXvIwi_rFw/s160-c/Delicate%252520Arch.jpg", "https://lh5.googleusercontent.com/-Oh8mMy2ieng/URqullDwehI/AAAAAAAAAbs/TbdeEfsaIZY/s160-c/Despair.jpg", "https://lh5.googleusercontent.com/-gl0y4UiAOlk/URqumC_KjBI/AAAAAAAAAbs/PM1eT7dn4oo/s160-c/Eagle%252520Fall%252520Sunrise.jpg", "https://lh3.googleusercontent.com/-hYYHd2_vXPQ/URqumtJa9eI/AAAAAAAAAbs/wAalXVkbSh0/s160-c/Electric%252520Storm.jpg", "https://lh5.googleusercontent.com/-PyY_yiyjPTo/URqunUOhHFI/AAAAAAAAAbs/azZoULNuJXc/s160-c/False%252520Kiva.jpg", "https://lh6.googleusercontent.com/-PYvLVdvXywk/URqunwd8hfI/AAAAAAAAAbs/qiMwgkFvf6I/s160-c/Fitzgerald%252520Streaks.jpg", "https://lh4.googleusercontent.com/-KIR_UobIIqY/URquoCZ9SlI/AAAAAAAAAbs/Y4d4q8sXu4c/s160-c/Foggy%252520Sunset.jpg", "https://lh6.googleusercontent.com/-9lzOk_OWZH0/URquoo4xYoI/AAAAAAAAAbs/AwgzHtNVCwU/s160-c/Frantic.jpg", "https://lh3.googleusercontent.com/-0X3JNaKaz48/URqupH78wpI/AAAAAAAAAbs/lHXxu_zbH8s/s160-c/Golden%252520Gate%252520Afternoon.jpg", "https://lh6.googleusercontent.com/-95sb5ag7ABc/URqupl95RDI/AAAAAAAAAbs/g73R20iVTRA/s160-c/Golden%252520Gate%252520Fog.jpg", "https://lh3.googleusercontent.com/-JB9v6rtgHhk/URqup21F-zI/AAAAAAAAAbs/64Fb8qMZWXk/s160-c/Golden%252520Grass.jpg", "https://lh4.googleusercontent.com/-EIBGfnuLtII/URquqVHwaRI/AAAAAAAAAbs/FA4McV2u8VE/s160-c/Grand%252520Teton.jpg", "https://lh4.googleusercontent.com/-WoMxZvmN9nY/URquq1v2AoI/AAAAAAAAAbs/grj5uMhL6NA/s160-c/Grass%252520Closeup.jpg", "https://lh3.googleusercontent.com/-6hZiEHXx64Q/URqurxvNdqI/AAAAAAAAAbs/kWMXM3o5OVI/s160-c/Green%252520Grass.jpg", "https://lh5.googleusercontent.com/-6LVb9OXtQ60/URquteBFuKI/AAAAAAAAAbs/4F4kRgecwFs/s160-c/Hanging%252520Leaf.jpg", "https://lh4.googleusercontent.com/-zAvf__52ONk/URqutT_IuxI/AAAAAAAAAbs/D_bcuc0thoU/s160-c/Highway%2525201.jpg", "https://lh6.googleusercontent.com/-H4SrUg615rA/URquuL27fXI/AAAAAAAAAbs/4aEqJfiMsOU/s160-c/Horseshoe%252520Bend%252520Sunset.jpg", "https://lh4.googleusercontent.com/-JhFi4fb_Pqw/URquuX-QXbI/AAAAAAAAAbs/IXpYUxuweYM/s160-c/Horseshoe%252520Bend.jpg", "https://lh5.googleusercontent.com/-UGgssvFRJ7g/URquueyJzGI/AAAAAAAAAbs/yYIBlLT0toM/s160-c/Into%252520the%252520Blue.jpg", "https://lh3.googleusercontent.com/-CH7KoupI7uI/URquu0FF__I/AAAAAAAAAbs/R7GDmI7v_G0/s160-c/Jelly%252520Fish%2525202.jpg", "https://lh4.googleusercontent.com/-pwuuw6yhg8U/URquvPxR3FI/AAAAAAAAAbs/VNGk6f-tsGE/s160-c/Jelly%252520Fish%2525203.jpg", "https://lh5.googleusercontent.com/-GoUQVw1fnFw/URquv6xbC0I/AAAAAAAAAbs/zEUVTQQ43Zc/s160-c/Kauai.jpg", "https://lh6.googleusercontent.com/-8QdYYQEpYjw/URquwvdh88I/AAAAAAAAAbs/cktDy-ysfHo/s160-c/Kyoto%252520Sunset.jpg", "https://lh4.googleusercontent.com/-vPeekyDjOE0/URquwzJ28qI/AAAAAAAAAbs/qxcyXULsZrg/s160-c/Lake%252520Tahoe%252520Colors.jpg", "https://lh4.googleusercontent.com/-xBPxWpD4yxU/URquxWHk8AI/AAAAAAAAAbs/ARDPeDYPiMY/s160-c/Lava%252520from%252520the%252520Sky.jpg", "https://lh3.googleusercontent.com/-897VXrJB6RE/URquxxxd-5I/AAAAAAAAAbs/j-Cz4T4YvIw/s160-c/Leica%25252050mm%252520Summilux.jpg", "https://lh5.googleusercontent.com/-qSJ4D4iXzGo/URquyDWiJ1I/AAAAAAAAAbs/k2pBXeWehOA/s160-c/Leica%25252050mm%252520Summilux.jpg", "https://lh6.googleusercontent.com/-dwlPg83vzLg/URquylTVuFI/AAAAAAAAAbs/G6SyQ8b4YsI/s160-c/Leica%252520M8%252520%252528Front%252529.jpg", "https://lh3.googleusercontent.com/-R3_EYAyJvfk/URquzQBv8eI/AAAAAAAAAbs/b9xhpUM3pEI/s160-c/Light%252520to%252520Sand.jpg", "https://lh3.googleusercontent.com/-fHY5h67QPi0/URqu0Cp4J1I/AAAAAAAAAbs/0lG6m94Z6vM/s160-c/Little%252520Bit%252520of%252520Paradise.jpg", "https://lh5.googleusercontent.com/-TzF_LwrCnRM/URqu0RddPOI/AAAAAAAAAbs/gaj2dLiuX0s/s160-c/Lone%252520Pine%252520Sunset.jpg", "https://lh3.googleusercontent.com/-4HdpJ4_DXU4/URqu046dJ9I/AAAAAAAAAbs/eBOodtk2_uk/s160-c/Lonely%252520Rock.jpg", "https://lh6.googleusercontent.com/-erbF--z-W4s/URqu1ajSLkI/AAAAAAAAAbs/xjDCDO1INzM/s160-c/Longue%252520Vue.jpg", "https://lh6.googleusercontent.com/-0CXJRdJaqvc/URqu1opNZNI/AAAAAAAAAbs/PFB2oPUU7Lk/s160-c/Look%252520Me%252520in%252520the%252520Eye.jpg", "https://lh3.googleusercontent.com/-D_5lNxnDN6g/URqu2Tk7HVI/AAAAAAAAAbs/p0ddca9W__Y/s160-c/Lost%252520in%252520a%252520Field.jpg", "https://lh6.googleusercontent.com/-flsqwMrIk2Q/URqu24PcmjI/AAAAAAAAAbs/5ocIH85XofM/s160-c/Marshall%252520Beach%252520Sunset.jpg", "https://lh4.googleusercontent.com/-Y4lgryEVTmU/URqu28kG3gI/AAAAAAAAAbs/OjXpekqtbJ4/s160-c/Mono%252520Lake%252520Blue.jpg", "https://lh4.googleusercontent.com/-AaHAJPmcGYA/URqu3PIldHI/AAAAAAAAAbs/lcTqk1SIcRs/s160-c/Monument%252520Valley%252520Overlook.jpg", "https://lh4.googleusercontent.com/-vKxfdQ83dQA/URqu31Yq_BI/AAAAAAAAAbs/OUoGk_2AyfM/s160-c/Moving%252520Rock.jpg", "https://lh5.googleusercontent.com/-CG62QiPpWXg/URqu4ia4vRI/AAAAAAAAAbs/0YOdqLAlcAc/s160-c/Napali%252520Coast.jpg", "https://lh6.googleusercontent.com/-wdGrP5PMmJQ/URqu5PZvn7I/AAAAAAAAAbs/m0abEcdPXe4/s160-c/One%252520Wheel.jpg", "https://lh6.googleusercontent.com/-6WS5DoCGuOA/URqu5qx1UgI/AAAAAAAAAbs/giMw2ixPvrY/s160-c/Open%252520Sky.jpg", "https://lh6.googleusercontent.com/-u8EHKj8G8GQ/URqu55sM6yI/AAAAAAAAAbs/lIXX_GlTdmI/s160-c/Orange%252520Sunset.jpg", "https://lh6.googleusercontent.com/-74Z5qj4bTDE/URqu6LSrJrI/AAAAAAAAAbs/XzmVkw90szQ/s160-c/Orchid.jpg", "https://lh6.googleusercontent.com/-lEQE4h6TePE/URqu6t_lSkI/AAAAAAAAAbs/zvGYKOea_qY/s160-c/Over%252520there.jpg", "https://lh5.googleusercontent.com/-cauH-53JH2M/URqu66v_USI/AAAAAAAAAbs/EucwwqclfKQ/s160-c/Plumes.jpg", "https://lh3.googleusercontent.com/-eDLT2jHDoy4/URqu7axzkAI/AAAAAAAAAbs/iVZE-xJ7lZs/s160-c/Rainbokeh.jpg", "https://lh5.googleusercontent.com/-j1NLqEFIyco/URqu8L1CGcI/AAAAAAAAAbs/aqZkgX66zlI/s160-c/Rainbow.jpg", "https://lh5.googleusercontent.com/-DRnqmK0t4VU/URqu8XYN9yI/AAAAAAAAAbs/LgvF_592WLU/s160-c/Rice%252520Fields.jpg", "https://lh3.googleusercontent.com/-hwh1v3EOGcQ/URqu8qOaKwI/AAAAAAAAAbs/IljRJRnbJGw/s160-c/Rockaway%252520Fire%252520Sky.jpg", "https://lh5.googleusercontent.com/-wjV6FQk7tlk/URqu9jCQ8sI/AAAAAAAAAbs/RyYUpdo-c9o/s160-c/Rockaway%252520Flow.jpg", "https://lh6.googleusercontent.com/-6cAXNfo7D20/URqu-BdzgPI/AAAAAAAAAbs/OmsYllzJqwo/s160-c/Rockaway%252520Sunset%252520Sky.jpg", "https://lh3.googleusercontent.com/-sl8fpGPS-RE/URqu_BOkfgI/AAAAAAAAAbs/Dg2Fv-JxOeg/s160-c/Russian%252520Ridge%252520Sunset.jpg", "https://lh6.googleusercontent.com/-gVtY36mMBIg/URqu_q91lkI/AAAAAAAAAbs/3CiFMBcy5MA/s160-c/Rust%252520Knot.jpg", "https://lh6.googleusercontent.com/-GHeImuHqJBE/URqu_FKfVLI/AAAAAAAAAbs/axuEJeqam7Q/s160-c/Sailing%252520Stones.jpg", "https://lh3.googleusercontent.com/-hBbYZjTOwGc/URqu_ycpIrI/AAAAAAAAAbs/nAdJUXnGJYE/s160-c/Seahorse.jpg", "https://lh3.googleusercontent.com/-Iwi6-i6IexY/URqvAYZHsVI/AAAAAAAAAbs/5ETWl4qXsFE/s160-c/Shinjuku%252520Street.jpg", "https://lh6.googleusercontent.com/-amhnySTM_MY/URqvAlb5KoI/AAAAAAAAAbs/pFCFgzlKsn0/s160-c/Sierra%252520Heavens.jpg", "https://lh5.googleusercontent.com/-dJgjepFrYSo/URqvBVJZrAI/AAAAAAAAAbs/v-F5QWpYO6s/s160-c/Sierra%252520Sunset.jpg", "https://lh4.googleusercontent.com/-Z4zGiC5nWdc/URqvBdEwivI/AAAAAAAAAbs/ZRZR1VJ84QA/s160-c/Sin%252520Lights.jpg", "https://lh4.googleusercontent.com/-_0cYiWW8ccY/URqvBz3iM4I/AAAAAAAAAbs/9N_Wq8MhLTY/s160-c/Starry%252520Lake.jpg", "https://lh3.googleusercontent.com/-A9LMoRyuQUA/URqvCYx_JoI/AAAAAAAAAbs/s7sde1Bz9cI/s160-c/Starry%252520Night.jpg", "https://lh3.googleusercontent.com/-KtLJ3k858eY/URqvC_2h_bI/AAAAAAAAAbs/zzEBImwDA_g/s160-c/Stream.jpg", "https://lh5.googleusercontent.com/-dFB7Lad6RcA/URqvDUftwWI/AAAAAAAAAbs/BrhoUtXTN7o/s160-c/Strip%252520Sunset.jpg", "https://lh5.googleusercontent.com/-at6apgFiN20/URqvDyffUZI/AAAAAAAAAbs/clABCx171bE/s160-c/Sunset%252520Hills.jpg", "https://lh4.googleusercontent.com/-7-EHhtQthII/URqvEYTk4vI/AAAAAAAAAbs/QSJZoB3YjVg/s160-c/Tenaya%252520Lake%2525202.jpg", "https://lh6.googleusercontent.com/-8MrjV_a-Pok/URqvFC5repI/AAAAAAAAAbs/9inKTg9fbCE/s160-c/Tenaya%252520Lake.jpg", "https://lh5.googleusercontent.com/-B1HW-z4zwao/URqvFWYRwUI/AAAAAAAAAbs/8Peli53Bs8I/s160-c/The%252520Cave%252520BW.jpg", 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main.xml如下:
gridview_item.xml如下:
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