Android之使用RatingBar设置游戏难度并保存

最近在学习游戏开发，在游戏中常常需要设置游戏的难度，在Android中我们可以使用RatingBar来实现。具体看下面的代码：

效果图如下：

package com.cloay.pt.ui;

import java.io.FileNotFoundException;
import java.io.IOException;

import android.content.ContentResolver;
import android.content.Intent;
import android.content.SharedPreferences;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.RatingBar;
import android.widget.RatingBar.OnRatingBarChangeListener;
import android.widget.TextView;

import com.cloay.pt.BasicActivity;
import com.cloay.pt.R;
import com.cloay.pt.constants.Constant;
import com.cloay.pt.utils.ImageUtil;

/**
* 游戏设置类,游戏难度等
* @author Cloay
* 2011-12-23
* 下午05:21:41
*/
public class SettingsActivity extends BasicActivity{
    private SharedPreferences settings; //保存设置
    private RatingBar ratingBar;
    private TextView defaultPicture;
    private TextView picture;
    private ImageView previewImage;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.settings);
        BasicActivity.allActivity.add(this);
        //初始化数据
        initData();
    }

    /**
     * 初始化数据
     */
    private void initData() {
        settings = getSharedPreferences("settings", 0);
        ratingBar = (RatingBar) findViewById(R.id.rating);
        //游戏默认图片
        defaultPicture = (TextView) findViewById(R.id.def);
        //从图库中选择图片，自定义
        picture = (TextView) findViewById(R.id.picture);
        previewImage = (ImageView)findViewById(R.id.preview);
        if("".equals(settings.getString("picture", ""))) {
            previewImage.setImageResource(R.drawable.def);
        }else{
            previewImage.setImageBitmap(ImageUtil.getBitmapFromSDCard(settings.getString("picture", "")));
        }
        //设置难度选择监听
        ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener() {
            @Override
            public void onRatingChanged(RatingBar ratingBar, float rating,
                    boolean fromUser) {
                settings.edit().putInt("level", (int)rating).commit();   //保存用户设置后的游戏难度
                showToast(SettingsActivity.this, (int)rating);
            }
        });
        //设置图片选择监听
        defaultPicture.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                settings.edit().putString("picture", "").commit();
                previewImage.setImageResource(R.drawable.def);
            }
        });
        picture.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                /* 开启Pictures画面Type设定为image */
                intent.setType("image/*");
                /* 使用Intent.ACTION_GET_CONTENT这个Action */
                intent.setAction(Intent.ACTION_GET_CONTENT);
                /* 取得相片后返回本画面 */
                startActivityForResult(intent, 1);
            }
        });

    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == RESULT_OK) {
            Uri uri = data.getData();
            ContentResolver cr = this.getContentResolver();
            try {  &n

补充：移动开发 , Android ,