/* * Copyright (C) 2007 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package com.example.android.apis.view;import com.example.android.apis.R;import android.app.ListActivity;import android.content.Context;import android.os.Bundle;import android.view.View;import android.view.ViewGroup;import android.view.ViewGroup.LayoutParams;import android.widget.BaseAdapter;import android.widget.Button;import android.widget.ImageView;import android.widget.AbsListView;import java.util.ArrayList;/** * A list view that demonstrates the use of setEmptyView. This example alos uses * a custom layout file that adds some extra buttons to the screen. */public class List8 extends ListActivity {    PhotoAdapter mAdapter;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        // Use a custom layout file        setContentView(R.layout.list_8);                // Tell the list view which view to display when the list is empty        getListView().setEmptyView(findViewById(R.id.empty));                // Set up our adapter        mAdapter = new PhotoAdapter(this);        setListAdapter(mAdapter);                // Wire up the clear button to remove all photos        Button clear = (Button) findViewById(R.id.clear);        clear.setOnClickListener(new View.OnClickListener() {            public void onClick(View v) {                mAdapter.clearPhotos();            } });                // Wire up the add button to add a new photo        Button add = (Button) findViewById(R.id.add);        add.setOnClickListener(new View.OnClickListener() {            public void onClick(View v) {                mAdapter.addPhotos();            } });    }    /**     * A simple adapter which maintains an ArrayList of photo resource Ids.      * Each photo is displayed as an image. This adapter supports clearing the     * list of photos and adding a new photo.     *     */    public class PhotoAdapter extends BaseAdapter {        private Integer[] mPhotoPool = {                R.drawable.sample_thumb_0, R.drawable.sample_thumb_1, R.drawable.sample_thumb_2,                R.drawable.sample_thumb_3, R.drawable.sample_thumb_4, R.drawable.sample_thumb_5,                R.drawable.sample_thumb_6, R.drawable.sample_thumb_7};        private ArrayList<Integer> mPhotos = new ArrayList<Integer>();                public PhotoAdapter(Context c) {            mContext = c;        }        public int getCount() {            return mPhotos.size();        }        public Object getItem(int position) {            return position;        }        public long getItemId(int position) {            return position;        }        public View getView(int position, View convertView, ViewGroup parent) {            // Make an ImageView to show a photo            ImageView i = new ImageView(mContext);            i.setImageResource(mPhotos.get(position));            i.setAdjustViewBounds(true);            i.setLayoutParams(new AbsListView.LayoutParams(LayoutParams.WRAP_CONTENT,                    LayoutParams.WRAP_CONTENT));            // Give it a nice background            i.setBackgroundResource(R.drawable.picture_frame);            return i;        }        private Context mContext;        public void clearPhotos() {            mPhotos.clear();            notifyDataSetChanged();        }                public void addPhotos() {            int whichPhoto = (int)Math.round(Math.random() * (mPhotoPool.length - 1));            int newPhoto = mPhotoPool[whichPhoto];            mPhotos.add(newPhoto);            notifyDataSetChanged();        }    }}