控件_SeekBar与RatingBar

这两种进度条都是ProgressBar的子类

SeekBar：是一种可以拖动的进度条，比如播放音乐的进度

import android.app.Activity;
import android.os.Bundle;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;

public class MainActivity extends Activity {
    private SeekBar seekbar;
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        seekbar = (SeekBar) findViewById(R.id.seekbar);
        seekbar.setProgress(30);
        seekbar.setSecondaryProgress(50);
        seekbar.setOnSeekBarChangeListener(new SeekBarListener());
    }
    
    class SeekBarListener implements OnSeekBarChangeListener{
        /*
         * seekbar 该对象指的是触发了监听器的SeekBar对象，就是说哪个SeekBar触发了监听器(因为有可能多个SeekBar绑定到这个监听器上)
         * progress 指的是当前SeekBar的进度
         * fromUser 表示进度的改变是否来自于用户，是则为true
         * */
        //该方法当进度条变化的时候调用
        public void onProgressChanged(SeekBar seekbar, int progress, boolean fromUser) {
            System.out.println("progress="+progress+",fromUser="+fromUser);
        }
        
        //当用户滑动进度条的时候调用
        public void onStartTrackingTouch(SeekBar seekBar) {
            System.out.println("Onstart");
        }

        //当用户终止滑动的时候调用
        public void onStopTrackingTouch(SeekBar seekBar) {
            System.out.println("Onstop");
        }
        
    }
}

<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" >

    <SeekBar
        android:id="@+id/seekbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:max="100"
        />

</RelativeLayout>

RatingBar：星星，就是用于评价星级

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RatingBar;
import android.widget.RatingBar.OnRatingBarChangeListener;

public class MainActivity extends Activity {
    private RatingBar ratingbar;
    private Button button;
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        ratingbar = (RatingBar) findViewById(R.id.ratingbar);
        ratingbar.setOnRatingBarChangeListener(new RatingBarListener());
        button = (Button)findViewById(R.id.button);
        button.setOnClickListener(new ButtonListener());
        
        
    }
    
    //该监听器只有onRatingChanged一个方法，第一个参数表示那个对象触发了监听器，第二个参数表示当前星数，第三个参数表示是否来自用户的改变
    class RatingBarListener implements OnRatingBarChangeListener{
        public void onRatingChanged(RatingBar ratingbar, float rating, boolean fromUser) {
            System.out.println("rating="+rating+",fromUser="+fromUser);
        }
    }
    
    class ButtonListener implements OnClickListener{
        public void onClick(View v) {
            ratingbar.setRating(ratingbar.getRating()+0.5f);
        }
    }
}

<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" >

    <RatingBar
        android:id="@+id/ratingbar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:numStars="5"
        android:stepSize="0.5"
        />
    
    <Button 
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/ratingbar"
        android:text="button"
        />

</RelativeLayout>
<!-- 
  android:numStars="4"     表示设置多少个星通常都是5个星
  android:progress="3"     设置当前的星数
  android:stepSize="0.5"   滑动的时候表示每次请进的距离，0。5就是每次半颗星，1就是一个星
 -->