安卓开发过程中的RatingBar、Handler以及GPS在大型项目中的使用【Android】

<RatingBar
        android:id="@+id/rb_normal"
        style="@style/roomRatingBar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

<style name="roomRatingBar" parent="@android:style/Widget.RatingBar">
        <item name="android:progressDrawable">@drawable/ratingbar_full</item>
        <item name="android:minHeight">24dip</item>
        <item name="android:maxHeight">24dip</item>
    </style>

public class MainActivity extends AppCompatActivity {
    private RatingBar rb_normal;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        rb_normal = (RatingBar) findViewById(R.id.rb_normal);
        rb_normal.setOnRatingBarChangeListener(new RatingBar.OnRatingBarChangeListener() {
            @Override
            public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) {
                Toast.makeText(MainActivity.this, "rating:" + String.valueOf(rating),
                        Toast.LENGTH_LONG).show();
            }
        });
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:tools="http://schemas.android.com/tools"  
    android:id="@+id/RelativeLayout1"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    android:gravity="center"  
    tools:context="com.jay.example.handlerdemo1.MainActivity" >  
  
    <ImageView  
        android:id="@+id/imgchange"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_alignParentLeft="true"  
        android:layout_alignParentTop="true" />  
  
</RelativeLayout> 

 int imgids[] = new int[]{  
        R.drawable.s_1, R.drawable.s_2,R.drawable.s_3,  
        R.drawable.s_4,R.drawable.s_5,R.drawable.s_6,  
        R.drawable.s_7,R.drawable.s_8  
    };  
    int imgstart = 0;  

 @Override  
                public void handleMessage(Message msg)  
                {  
                    if(msg.what == 0x123)  
                    {  
                        int upper = msg.getData().getInt(UPPER_NUM);  
                        List<Integer> nums = new ArrayList<Integer>();  
                        // 计算从2开始、到upper的所有质数  
                        outer:  
                        for (int i = 2 ; i <= upper ; i++)  
                        {  
                            // 用i处于从2开始、到i的平方根的所有数  
                            for (int j = 2 ; j <= Math.sqrt(i) ; j++)  
                            {  
                                // 如果可以整除，表明这个数不是质数  
                                if(i != 2 && i % j == 0)  
                                {  
                                    continue outer;  
                                }  
                            }  
                            nums.add(i);  
                        }  
                        // 使用Toast显示统计出来的所有质数  
                        Toast.makeText(CalPrime.this , nums.toString()  
                            , Toast.LENGTH_LONG).show();  
                    }  
                }  

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        bindViews();
    }

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />