解析android中ProgressBar的用法

/* import程序略 */

public class EX04_17 extends Activity
{
  private TextView mTextView01;
  private Button mButton01;
  private ProgressBar mProgressBar01;
  public int intCounter=0;

  /* 自定义Handler信息代码，用以作为标识事件处理 */
  protected static final int GUI_STOP_NOTIFIER = 0x108;
  protected static final int GUI_THREADING_NOTIFIER = 0x109;

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    mButton01 = (Button)findViewById(R.id.myButton1);
    mTextView01 = (TextView)findViewById(R.id.myTextView1);

    /* 设置ProgressBar widget对象 */
    mProgressBar01 = (ProgressBar)findViewById(R.id.myProgressBar1);

    /* 调用setIndeterminate方法赋值indeterminate模式为false */
    mProgressBar01.setIndeterminate(false);

    /* 当单击按钮后，开始进程工作 */
    mButton01.setOnClickListener(new Button.OnClickListener()
    {
      @Override
      public void onClick(View v)
      {
        // TODO Auto-generated method stub

        /* 单击按钮让ProgressBar显示 */
        mTextView01.setText(R.string.str_progress_start);

        /* 将隐藏的ProgressBar显示出来 */
        mProgressBar01.setVisibility(View.VISIBLE);

        /* 指定Progress为最多100 */
        mProgressBar01.setMax(100);

        /* 初始Progress为0 */
        mProgressBar01.setProgress(0);

        /* 开始一个进程 */
        new Thread(new Runnable()
        {
          public void run()
          {
            /* 默认0至9，共运行10次的循环语句 */
            for (int i=0;i<10;i++)
            {
              try
              {
                /* 成员变量，用以识别加载进度 */
                intCounter = (i+1)*20;
                /* 每运行一次循环，即暂停1秒 */
                Thread.sleep(1000);

                /* 当Thread运行5秒后显示运行结束 */
                if(i==4)
                {
                  /* 以Message对象，传递参数给Handler */
                  Message m = new Message();

                  /* 以what属性指定User自定义 */
                  m.what = EX04_17.GUI_STOP_NOTIFIER;
                  EX04_17.this.myMessageHandler.sendMessage(m);
                  break;
                }
                else
                {
                  Message m = new Message();
                  m.what = EX04_17.GUI_THREADING_NOTIFIER;
                  EX04_17.this.myMessageHandler.sendMessage(m);
                }
              }
              catch(Exception e)
              {
                e.printStackTrace();
              }
            }
          }
        }).start();
      }
    });
  }

  /* Handler构建之后，会监听传来的信息代码 */
  Handler myMessageHandler = new Handler()
  {
    // @Override
    public void handleMessage(Message msg)
    {
      switch (msg.what)
      {
        /* 当取得标识为离开进程时所取得的信息 */
        case EX04_17.GUI_STOP_NOTIFIER:

          /* 显示运行终了 */
          mTextView01.setText(R.string.str_progress_done);

          /* 设置ProgressBar Widget为隐藏 */
          mProgressBar01.setVisibility(View.GONE);
          Thread.currentThread().interrupt();
          break;

        /* 当取得标识为持续在进程当中时所取得的信息 */
        case EX04_17.GUI_THREADING_NOTIFIER:
          if(!Thread.currentThread().isInterrupted())
          {
            mProgressBar01.setProgress(intCounter);
            /* 将显示进度显示于TextView当中 */
            mTextView01.setText
            (
              getResources().getText(R.string.str_progress_start)+
              "("+Integer.toString(intCounter)+"%)/n"+
              "Progress:"+
              Integer.toString(mProgressBar01.getProgress())+
              "/n"+"Indeterminate:"+
              Boolean.toString(mProgressBar01.isIndeterminate())
            );
          }
          break;
      }
      super.handleMessage(msg);
    }
  };
}

<ProgressBar
  android:id="@+id/myProgressBar1"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:max="100"
  android:progress="0"
  android:orientation="horizontal"
  android:progressBarStyle=
  "@android:style/Widget.ProgressBar.Horizontal"
  android:indeterminateOnly="false"
  android:visibility="gone"
/>

<resources>
  <declare-styleable name="Theme">
  <!-- snip -->
  <attr name="progressBarStyleHorizontal" format="reference" />
</resources>

<resources>
  <style name="Widget.ProgressBar.Horizontal">
    <item name="android:indeterminateOnly">false</item>
    <item name="android:progressDrawable">
      @android:drawable/progress_horizontal
    </item>
    <item name="android:indeterminateDrawable">
      @android:drawable/progress_indeterminate_horizontal
    </item>
    <item name="android:minHeight">20dip</item>
    <item name="android:maxHeight">20dip</item>
  </style>
</resources>

android:progressDrawable="@android:drawable/progress_horizontal"
android:indeterminateDrawable=
"@android:drawable/progress_indeterminate_horizontal"