package com.example.listviewanimationdemo.itemanimation; import java.util.ArrayList; import java.util.List; import android.annotation.SuppressLint; import android.content.Context; import android.content.Intent; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.Build; import android.os.Bundle; import android.support.v4.app.FragmentActivity; import android.support.v4.util.LruCache; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.GridView; import android.widget.ImageView; import com.example.listviewanimationdemo.R; import com.nhaarman.listviewanimations.ArrayAdapter; import com.nhaarman.listviewanimations.swinginadapters.prepared.SwingBottomInAnimationAdapter; public class GridViewActivity extends FragmentActivity { public static void actionToGridView(Context context) { Intent intent = new Intent(context, GridViewActivity.class); context.startActivity(intent); } @SuppressLint("InlinedApi") @Override protected void onCreate(final Bundle savedInstanceState) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) { getWindow() .addFlags( android.view.WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION); } super.onCreate(savedInstanceState); setTitle("Gridview动画"); setContentView(R.layout.activity_gridview); GridView gridView = (GridView) findViewById(R.id.activity_gridview_gv); SwingBottomInAnimationAdapter swingBottomInAnimationAdapter = new SwingBottomInAnimationAdapter( new MyAdapter(this, getItems())); swingBottomInAnimationAdapter.setAbsListView(gridView); swingBottomInAnimationAdapter.setInitialDelayMillis(300); gridView.setAdapter(swingBottomInAnimationAdapter); } private ArrayList<Integer> getItems() { ArrayList<Integer> items = new ArrayList<Integer>(); for (int i = 0; i < 100; i++) { items.add(i); } return items; } private static class MyAdapter extends ArrayAdapter<Integer> { private final Context mContext; private final LruCache<Integer, Bitmap> mMemoryCache; public MyAdapter(final Context context, final List<Integer> list) { super(list); mContext = context; final int cacheSize = (int) (Runtime.getRuntime().maxMemory() / 1024); mMemoryCache = new LruCache<Integer, Bitmap>(cacheSize) { @Override protected int sizeOf(final Integer key, final Bitmap bitmap) { // The cache size will be measured in kilobytes rather than // number of items. return bitmap.getRowBytes() * bitmap.getHeight() / 1024; } }; } @Override public View getView(final int position, final View convertView, final ViewGroup viewGroup) { ImageView imageView = (ImageView) convertView; if (imageView == null) { imageView = new ImageView(mContext); imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); } int imageResId; switch (getItem(position) % 5) { case 0: imageResId = R.drawable.img_nature1; break; case 1: imageResId = R.drawable.img_nature2; break; case 2: imageResId = R.drawable.img_nature3; break; case 3: imageResId = R.drawable.img_nature4; break; default: imageResId = R.drawable.img_nature5; } Bitmap bitmap = getBitmapFromMemCache(imageResId); if (bitmap == null) { bitmap = BitmapFactory.decodeResource(mContext.getResources(), imageResId); addBitmapToMemoryCache(imageResId, bitmap); } imageView.setImageBitmap(bitmap); return imageView; } private void addBitmapToMemoryCache(final int key, final Bitmap bitmap) { if (getBitmapFromMemCache(key) == null) { mMemoryCache.put(key, bitmap); } } private Bitmap getBitmapFromMemCache(final int key) { return mMemoryCache.get(key); } } @Override public boolean onOptionsItemSelected(final MenuItem item) { switch (item.getItemId()) { case android.R.id.home: finish(); return true; default: return super.onOptionsItemSelected(item); } } }