当前页面: 开发资料首页 → J2ME 专题 → 为TextBox组件创建简单的剪贴板(Matrix-corej2me系列)

为TextBox组件创建简单的剪贴板(Matrix-corej2me系列)

摘要: 为TextBox组件创建简单的剪贴板(Matrix-corej2me系列)

内容: 在Core J2ME Technology and MIDP一书中许多的可以在多个多行编辑组件(multiple TextBox)中共享剪贴板数据的例子。

注意：这个例子基于MIDP与CLDC 1.0.3版
本文得到作者John W. Muchow的允许，部分引用了Core J2ME Technology and MIDP, Sun Microsystems与Prentice Hall出版社 2002 Sun Microsystems Inc, 的内容。

源代码：

/*--------------------------------------------------
* SimpleClipBoard.java
*
* Example from the book:  Core J2ME Technology
* Copyright John W. Muchow http://www.CoreJ2ME.com
* You may use/modify for any non-commercial purpose
*-------------------------------------------------*/
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class SimpleClipBoard extends MIDlet implements CommandListener
{
 private Display display;   // 对显示对象的引用Reference to Display object
 private TextBox tbClip;  // 主TextBox组件Main textbox
 private Command cmExit;  // 退出命令Command to exit
 private Command cmStartMark; // 开始标记命令Command to start marking a block
 private Command cmCopy;  // 复制剪贴板命令Command to copy to clipboard 
 private Command cmPaste;  // 粘贴剪贴板命令Command to paste into textbox
 private int beginOffset = 0; // 复制的开始索引The start index of copy
 private char[] clipBoard = null; // 剪贴板The clipboard
 private int clipBoardChars = 0; // 记录剪贴板中的字符Number of chars in clipboard
 
 public SimpleClipBoard()
 {
 display = Display.getDisplay(this);

 // Create the Commands. Notice the priorities assigned
 cmExit = new Command("Exit", Command.EXIT, 1);
 cmStartMark = new Command("Mark", Command.SCREEN, 2);
 cmCopy = new Command("Copy", Command.SCREEN, 3);
 cmPaste = new Command("Paste", Command.SCREEN, 4);

 tbClip = new TextBox("Clip Board", "Tee to grn", 15, TextField.ANY);
 tbClip.addCommand(cmExit);
 tbClip.addCommand(cmStartMark);
 tbClip.addCommand(cmCopy);
 tbClip.addCommand(cmPaste); 
 tbClip.setCommandListener(this);
 
 // Allocate a clipboard big enough to hold the entire textbox
 clipBoard = new char[tbClip.getMaxSize()];
 }
   
 public void startApp() 
 {
 display.setCurrent(tbClip);
 }
 
 public void pauseApp()
 {
 }
  
 public void destroyApp(boolean unconditional)
 {
 }

 public void commandAction(Command c, Displayable s)
 {
 if (c == cmStartMark)
 {
  beginOffset = tbClip.getCaretPosition();
 }
 else if (c == cmCopy && (tbClip.getCaretPosition() > beginOffset))
 {
  // Allocate an array to hold the current textbox contents
  char[] chr = new char[tbClip.size()];
  
  // Get the current textbox contents
  tbClip.getChars(chr);

  // The count of characters in the clipboard  
  clipBoardChars = tbClip.getCaretPosition() - beginOffset;
  
  // Copy the text into the clipboard
  // arraycopy(source, sourceindex, dest, destindex, count)  
  System.arraycopy(chr, beginOffset, clipBoard, 0, clipBoardChars);
 }
 else if (c == cmPaste)
 {
  // Make sure the paste will not overrun the textbox length.
  if ((tbClip.size() + clipBoardChars) <= tbClip.getMaxSize())
  tbClip.insert(clipBoard, 0, clipBoardChars, tbClip.getCaretPosition());
 }
 else if (c == cmExit)
 {
  destroyApp(false);
  notifyDestroyed();
 }  
 }
}

源代码下载:
下载

关于翻译作者:

bruceyuki,JAVA C#技术爱好者，现就读于新西兰奥克兰大学，正参与大学的一个AI项目,可以点击http://www.matrix.org.cn/user_view.asp?username=bruceyuki查看他的个人信息

↑返回目录
前一篇: 在组件(components)之间共享Ticker
后一篇: 深入MIDIetStateChangeException