android学习笔记九——RatingBar

RatingBar==>星级评分条

RatingBar和SeekBar十分相似，它们甚至有相同的父类：AbsSeekBar.两者都允许用户通过拖动来改变进度；

两者最大的区别在于RatingBar是通过星星表示进度；RatingBar本身就是一个特殊的SeekBar。

RatingBar常见XML属性如下图：

注意：为了程序支持响应星级评分条的改变，程序可以考虑为其绑定一个OnRatingBarChangeLinstener监听器。

实例如下：

布局文件==》
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >
 
  <!--   <ImageView
        android:id="@+id/image"
        android:layout_width="wrap_content"
        android:layout_height="200px"
        android:src="@drawable/no" />-->
      
    <RatingBar
        android:id="@+id/ratingbar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:max="255"
        android:numStars="5"
        android:progress="255"
        android:stepSize="0.5" />
 
</RelativeLayout>
 
代码实现==》
package com.example.myratingbar;
 
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.ImageView;
import android.widget.RatingBar;
import android.widget.RatingBar.OnRatingBarChangeListener;
 
public class MainActivity extends Activity
{
 
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        RatingBar bar = (RatingBar) this.findViewById(R.id.ratingbar);
        //final ImageView img = (ImageView) this.findViewById(R.id.image);
 
        bar.setOnRatingBarChangeListener(new OnRatingBarChangeListener()
        {
            @SuppressWarnings("deprecation")
            @Override
            public void onRatingChanged(RatingBar ratingBar, float rating,
                    boolean fromUser)
            {
                //img.setAlpha((int) (rating * 255 / 5));
            }
        });
    }
 
    @Override
    public boolean onCreateOptionsMenu(Menu menu)
    {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
 
}

实现效果如：

如何替换如上图系统默认星星图标，实现方式如下：

参考：http://my.oschina.net/amigos/blog/60060

drawable-mdpl资源文件==》

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
 
    <item
        android:id="@+android:id/background"
        android:drawable="@drawable/unselect">
    </item>
    <item
        android:id="@+android:id/secondaryProgress"
        android:drawable="@drawable/unselect">
    </item>
    <item
        android:id="@+android:id/progress"
        android:drawable="@drawable/select">
    </item>
 
</layer-list>

　样式文件==》style.xml

<style name="roomRatingBar" parent="@android:style/Widget.RatingBar">
       <item name="android:progressDrawable">@drawable/ratingbar_drawable</item>
       <item name="android:minHeight">48dip</item>
       <item name="android:maxHeight">48dip</item>
   </style>

加布局文件==》

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity" >
 
    <RatingBar
        android:id="@+id/ratingbar"
        style="@style/roomRatingBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dip"
        android:numStars="8"
        android:rating="1.5"
        android:stepSize="0.15" />
 
</LinearLayout>