www.pudn.com > 20049791944754.zip > WaitCanvas.java

/* License
 * 
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
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 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
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 * Neither the name of Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *  
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
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 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
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import java.util.*; 
 
import javax.microedition.lcdui.*; 
 
public class WaitCanvas 
    extends Canvas { 
  private int mCount, mMaximum; 
  private int mInterval; 
   
  private int mWidth, mHeight, mX, mY, mRadius; 
  private String mMessage; 
   
  public WaitCanvas() { 
    mCount = 0; 
    mMaximum = 36; 
    mInterval = 100; 
     
    mWidth = getWidth(); 
    mHeight = getHeight(); 
     
    // Calculate the radius. 
    int halfWidth = (mWidth - mRadius) / 2; 
    int halfHeight = (mHeight - mRadius) / 2; 
    mRadius = Math.min(halfWidth, halfHeight); 
     
    // Calculate the location. 
    mX = halfWidth - mRadius / 2; 
    mY = halfHeight - mRadius / 2; 
 
    // Create a Timer to update the display. 
    TimerTask task = new TimerTask() { 
      public void run() { 
        mCount = (mCount + 1) % mMaximum; 
        repaint(); 
      } 
    }; 
    Timer timer = new Timer(); 
    timer.schedule(task, 0, mInterval); 
  } 
   
  public void setMessage(String s) { 
    mMessage = s; 
    repaint(); 
  } 
   
  public void paint(Graphics g) { 
    int theta = -(mCount * 360 / mMaximum); 
     
    // Clear the whole screen. 
    g.setColor(255, 255, 255); 
    g.fillRect(0, 0, mWidth, mHeight); 
     
    // Now draw the pinwheel. 
    g.setColor(0, 0, 0); 
    g.drawArc(mX, mY, mRadius, mRadius, 0, 360); 
    g.fillArc(mX, mY, mRadius, mRadius, theta +  90, 90); 
    g.fillArc(mX, mY, mRadius, mRadius, theta + 270, 90); 
     
    // Draw the message, if there is a message. 
    if (mMessage != null) 
      g.drawString(mMessage, mWidth / 2, mHeight, 
          Graphics.BOTTOM | Graphics.HCENTER); 
  } 
}