drawcanvas.java

几个不错的手机程序例子

/*
 * DrawCanvas.java
 *
 * Copyright 2001 SkyArts. All Rights Reserved.
 */
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import java.io.*;

/**
 * 从资源中读出与描绘用的Canvas类
 *
 * @author  Hideki Yonekawa
 * @version 1.0
 */
class DrawCanvas extends Canvas implements  CommandListener {
	/** 存放画面宽度的变量 */
	private int					screenWidth;
	/** 存放画面高度的变量 */
	private int					screenHeight;

	/** 存放ResourceRead对象--MIDlet的变量 */
	private ResourceRead		resourceRead;

	/** Exit指令变量 */
	private Command				exitCmd			= new Command("Exit", Command.SCREEN, 5);

	/** 存放画面显示用字符串的变量 */
	private String				drawSt;

	/** 构造函数 */
	DrawCanvas(ResourceRead resourceRead) {
		this.resourceRead = resourceRead;

		//取得宽度与高度
		screenWidth = getWidth();
		screenHeight = getHeight();

		//读取数据文件
		InputStreamReader reader = null;
		try {
			InputStream in = getClass().getResourceAsStream("/resouce.txt");
			if(in != null) {
				reader = new InputStreamReader(in);
				char[] readChar = new char[128];
				int readLength;
				StringBuffer readStBuffer = new StringBuffer();
				while((readLength = reader.read(readChar, 0, readChar.length)) > -1) {
					readStBuffer.append(new String(readChar, 0, readLength));
				}
				drawSt = readStBuffer.toString();
			} else {
				drawSt = "Resouce not found.";
			}
		}catch (java.io.IOException ex) {
			ex.printStackTrace();
		}finally {
			if(reader != null) {
				try {
					reader.close();
				}catch(Exception e) {
					e.printStackTrace();
				}
			}
		}

/*
		DataInputStream din = null;
		try {
			InputStream in = getClass().getResourceAsStream("/resouce.txt");
			if(in != null) {
				din = new DataInputStream(in);
				drawSt = din.readUTF();
			} else {
				drawSt = "Resouce not found.";
			}
		}catch (java.io.IOException ex) {
			ex.printStackTrace();
		}finally {
			if(din != null) {
				try {
					din.close();
				}catch(Exception e) {
					e.printStackTrace();
				}
			}
		}
*/
/*
		DataInputStream din = null;
		try {
			InputStream in = getClass().getResourceAsStream("/resouce.txt");
			if(in != null) {
				din = new DataInputStream(in);
				byte[] readByte = new byte[128];
				int readLength;
				ByteArrayOutputStream byteStream = new ByteArrayOutputStream();

				while((readLength = din.read(readByte)) > -1) {
					byteStream.write(readByte, 0, readLength);
				}
				drawSt = new String(byteStream.toByteArray());

				readByte = byteStream.toByteArray();
				for(int i=0; i < readByte.length; i++) {
					System.out.println(Integer.toHexString( (int)readByte[i] ));
				}


			} else {
				drawSt = "Resouce not found.";
			}
		}catch (java.io.IOException ex) {
			ex.printStackTrace();
		}finally {
			if(din != null) {
				try {
					din.close();
				}catch(Exception e) {
					e.printStackTrace();
				}
			}
		}
*/


/*
		InputStream in = null;
		try {
			in = getClass().getResourceAsStream("/resouce.txt");
			if(in != null) {
				int readInt;
//				StringBuffer readBuffer = new StringBuffer();
				byte[] readBytes = new byte[128];
				ByteArrayOutputStream byteOut = new ByteArrayOutputStream(); 
				while((readInt = in.read(readBytes)) > -1) {
//					readBuffer.append((char)readInt);
					byteOut.write(readBytes, 0, readInt);
				}
//				drawSt = readBuffer.toString();
//				drawSt = byteOut.toString();
				drawSt = new String(byteOut.toString());

			} else {
				drawSt = "Resouce not found.";
			}
		}catch (java.io.IOException ex) {
			ex.printStackTrace();
		}finally {
			if(in != null) {
				try {
					in.close();
				}catch(Exception e) {
					e.printStackTrace();
				}
			}
		}
*/

/*
		InputConnection conn = null;
		try {
//			String url = "jar://" + rsName + "/" + fileName;
			String url = "jar://" + "resouce.txt";
			System.out.println("----- jar: connection URL: " + url);
			conn = ( InputConnection ) Connector.open( url, Connector.READ );
			InputStream in = conn.openInputStream();
			System.out.println("----- jar: connecting, expected byte count = " );
			byte[] readBytes = new byte[128];
				int readInt;
			ByteArrayOutputStream byteOut = new ByteArrayOutputStream(); 
			while((readInt = in.read(readBytes)) > -1) {
//					readBuffer.append((char)readInt);
				byteOut.write(readBytes, 0, readInt);
			}
			in.close();

			drawSt = new String(byteOut.toString());

/*
			} else {
				drawSt = "Resouce not found.";
			}
*/
/*
		}catch (java.io.IOException ex) {
			ex.printStackTrace();
		}finally {
			if(conn != null) {
				try {
					conn.close();
				}catch(Exception e) {
					e.printStackTrace();
				}
			}
		}

*/

//		System.out.println(getClass().getResourceAsStream("/resouce.txt"));

		addCommand(exitCmd);

		//登录Command listeners
		setCommandListener(this);
	}



	/**
	 * 描绘用的方法。通常不会直接由自己类来调用
	 * @param	g	Graphics对象
	 */
	protected void paint(Graphics g) {
		//背景涂白
		g.setColor(0x00FFFFFF);
		g.fillRect(0, 0, screenWidth, screenHeight);
		
		g.setColor(0x00000000);
		g.drawString(drawSt, 0, 0, Graphics.TOP|Graphics.LEFT);
	}

	/** 指令的事件发生时所调用的方法 */
	public void commandAction(Command c, Displayable s) {
		if(c == exitCmd) {//EXIT指令
			//调用NetworkTestImg类的doExit方法，并结束MIDlet
			resourceRead.doExit();
		}
	}
}