wallpaper.java

android first home screen

/*
 * Copyright (C) 2006 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.home;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.Gallery.LayoutParams;

import java.io.IOException;
import java.io.InputStream;

/**
 * Wallpaper picker for the Home application. User can choose from a gallery of stock photos.
 */
public class Wallpaper extends Activity implements AdapterView.OnItemSelectedListener, AdapterView.OnItemClickListener
{

	private static final String LOG_TAG = "Home";

	private static final Integer[] THUMB_IDS = { R.drawable.bg_android_icon, R.drawable.bg_sunrise_icon, R.drawable.bg_sunset_icon, };

	private static final Integer[] IMAGE_IDS = { R.drawable.bg_android, R.drawable.bg_sunrise, R.drawable.bg_sunset, };

	private Gallery mGallery;
	private boolean mIsWallpaperSet;

	@Override
	public void onCreate(Bundle icicle)
	{
		super.onCreate(icicle);
		requestWindowFeature(Window.FEATURE_NO_TITLE);

		setContentView(R.layout.wallpaper);

		mGallery = (Gallery) findViewById(R.id.gallery);
		mGallery.setAdapter(new ImageAdapter(this));
		mGallery.setOnItemSelectedListener(this);
		mGallery.setOnItemClickListener(this);
	}

	@Override
	protected void onResume()
	{
		super.onResume();
		mIsWallpaperSet = false;
	}

	public void onItemSelected(AdapterView parent, View v, int position, long id)
	{
		getWindow().setBackgroundDrawableResource(IMAGE_IDS[position]);
	}

	public void onItemClick(AdapterView parent, View v, int position, long id)
	{
		selectWallpaper(position);
	}

	/*
	 * When using touch if you tap an image it triggers both the onItemClick and the onTouchEvent causing the wallpaper to be set twice. Synchronize this method and ensure we only set the wallpaper once.
	 */
	private synchronized void selectWallpaper(int position)
	{
		if (mIsWallpaperSet)
		{
			return;
		}
		mIsWallpaperSet = true;
		try
		{
			InputStream stream = getResources().openRawResource(IMAGE_IDS[position]);
			setWallpaper(stream);
			setResult(RESULT_OK);
			finish();
		}
		catch (IOException e)
		{
			Log.e(LOG_TAG, "Failed to set wallpaper " + e);
		}
	}

	public void onNothingSelected(AdapterView parent)
	{
	}

	@Override
	public boolean onTouchEvent(MotionEvent event)
	{
		selectWallpaper(mGallery.getSelectedItemPosition());
		return true;
	}

	public class ImageAdapter extends BaseAdapter
	{

		private Context mContext;

		public ImageAdapter(Context c)
		{
			mContext = c;
		}

		public int getCount()
		{
			return THUMB_IDS.length;
		}

		public Object getItem(int position)
		{
			return position;
		}

		public long getItemId(int position)
		{
			return position;
		}

		public View getView(final int position, View convertView, ViewGroup parent)
		{
			ImageView i = new ImageView(mContext);

			i.setImageResource(THUMB_IDS[position]);
			i.setAdjustViewBounds(true);
			i.setLayoutParams(new Gallery.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
			i.setBackgroundResource(android.R.drawable.picture_frame);
			return i;
		}

	}

}