下拉列表、拖動條與星級評分條都是Android中的一些基本元件。

寫一個小小的程式，來說明其用法。

如下圖：

當下拉列表有值選定之後，則彈出相應的提示資訊，哪個值被選擇。星際評分條也一樣，獲取使用者選擇的星數。

標籤文字被觸控則顯示其被觸控。

滑動條，在拖動的時候，則在標籤文字顯示其值。因為，如果用彈出訊息顯示其滑動值，很不順暢。

首先，把res\values\strings.xml，修改成如下程式碼：

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="app_name">進度條及其他元件</string>
    <string name="action_settings">Settings</string>
    <string name="TextView1">下拉列表：</string>
    <string name="TextView2">拖動條：</string>
    <string name="TextView3">星級評分條：</string>
</resources>
 

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string-array name="spinner1">
        <item>選項1</item>
        <item>選項2</item>
        <item>選項3</item>
    </string-array>

</resources>
 

因此activity_main.xml的程式碼如下，給要操作的元件賦予id：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/TextView1" />

        <Spinner
            android:id="@+id/spinner1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:entries="@array/spinner1" />
    </LinearLayout>

    <TextView
        android:id="@+id/TextView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/TextView2" />

    <SeekBar
        android:id="@+id/seekBar1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/TextView3" />

    <RatingBar
        android:id="@+id/ratingBar1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:numStars="5" />

</LinearLayout>
 

之後在Mainactivity.java中給各個元件新增監聽器：

package com.progresscomponent;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.RatingBar;
import android.widget.RatingBar.OnRatingBarChangeListener;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {
	private Spinner spinner1;
	private TextView textView2;
	private SeekBar seekBar1;
	private RatingBar ratingBar1;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		//獲取各個元件
		spinner1=(Spinner)findViewById(R.id.spinner1);
		textView2 = (TextView) findViewById(R.id.TextView2);
		seekBar1=(SeekBar)findViewById(R.id.seekBar1);
		ratingBar1=(RatingBar)findViewById(R.id.ratingBar1);
		//下拉列表的改變的監聽器
		spinner1.setOnItemSelectedListener(new OnItemSelectedListener() {
			@Override
			public void onItemSelected(AdapterView<?> parent, View arg1,
					int pos, long arg3) {
				String result=parent.getItemAtPosition(pos).toString();
				Toast.makeText(MainActivity.this, "下拉列表被更改，"+result+"被選擇",
						Toast.LENGTH_LONG).show();				
			}
			@Override
			public void onNothingSelected(AdapterView<?> arg0) {
				// TODO Auto-generated method stub				
			}			
		});
		//標籤文字被觸控的監聽器
		textView2.setOnTouchListener(new OnTouchListener() {
			@Override
			public boolean onTouch(View arg0, MotionEvent arg1) {
				Toast.makeText(MainActivity.this, "“拖動條”這幾個字被觸控！",
						Toast.LENGTH_LONG).show();
				return false;
			}
		});
		//滑動條被拖動的監聽器
		seekBar1.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
			
			@Override
			public void onStopTrackingTouch(SeekBar arg0) {
				// TODO Auto-generated method stub
				
			}
			
			@Override
			public void onStartTrackingTouch(SeekBar arg0) {
				// TODO Auto-generated method stub
				
			}
			
			@Override
			public void onProgressChanged(SeekBar arg0, int result, boolean arg2) {
				// TODO Auto-generated method stub
				textView2.setText( "滑動條，當前值為："+result);
			}
		});
		//星級評分條被打分的監聽器
		ratingBar1.setOnRatingBarChangeListener(new OnRatingBarChangeListener() {
			
			@Override
			public void onRatingChanged(RatingBar arg0, float result, boolean arg2) {
				Toast.makeText(MainActivity.this, "星級評分條被評分，值為："+result,
						Toast.LENGTH_LONG).show();					
			}
		});
	}

	@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;
	}

}