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/*
* 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();
}
}
}
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