进度条控件的使用

package com.example.helloworld;

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

/**
 * 常用控件三 ProgressBar ListView
 * 
 * @author David
 * 
 */
public class TenLessonDemo1 extends Activity {

    private ProgressBar firstBar = null;
    private ProgressBar secondBar = null;
    private Button myButton = null;
    private int i = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        this.setContentView(R.layout.tenone);
        firstBar = (ProgressBar) findViewById(R.id.firstBar);
        secondBar = (ProgressBar) findViewById(R.id.secondBar);
        myButton = (Button) findViewById(R.id.myButton);
        myButton.setOnClickListener(new ButtonListener());
        System.out.println(firstBar.getMax());
    }

    class ButtonListener implements OnClickListener {

        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            if (i == 0) {
                firstBar.setVisibility(View.VISIBLE);//设置进度条处于可见状态
                secondBar.setVisibility(View.VISIBLE);
            } else if (i < firstBar.getMax()) {
                firstBar.setProgress(i);//设置进度条的当前值
                firstBar.setSecondaryProgress(i + 10);//进度条的第二颜色
                secondBar.setProgress(i);//这样做是没有作用的，因为默认的进度条是无法显示进行的状态的
            } else {
                firstBar.setVisibility(View.GONE);
                secondBar.setVisibility(View.GONE);//设置进度条处于不可见状态

            }
            i = i + 10;
        }
    }
}

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

    <TextView
        android:id="@+id/textView1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="hello" />

    <ProgressBar
        android:id="@+id/firstBar"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:max="200"
        android:visibility="gone" />

    <ProgressBar
        android:id="@+id/secondBar"
        style="?android:attr/progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:visibility="gone" />

    <Button
        android:id="@+id/myButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="确定" />

</LinearLayout>