scrollcanvas.java

example2 众多JAVA实例源码...学习java基础的好帮手

package opusmicro.demos.scroll3;

import java.util.Vector;

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Graphics;

public class ScrollCanvas extends Canvas implements Runnable{

	private int position = 0;
	Vector children = new Vector();
	private int start = 0;
	private int width, height;
	private ScrollItem item;
	private int scrollbarwidth = 6;
	private boolean positionchange;
	boolean pause = false;
	boolean isKeepGoing = true;
	boolean isGameA = false;
	boolean isGameB = false;
	private boolean isPressed;
	int gx = -999;
	protected byte[] keyCode;
	byte index;
	
	public ScrollCanvas(){
		width = getWidth();
		height = getHeight();
		keyCode = new byte[2];
		new Thread(this).start();
	}
	public void addChild(ScrollItem item){
		if(!children.contains(item)){
			children.addElement(item);
		}
	}
	void preposition(){
		if(position>0){
			position--;
		}
		positionchange = true;
		repaint();
		serviceRepaints();
	}
	void nextposition(){
		if(position<children.size()-1){
			position++;
		}
		positionchange = true;
		repaint();
		serviceRepaints();
	}
	public void keyPressed(int keyCode){
		gx = getGameAction(keyCode);
//		gx = keyCode;
		start(keyCode);
		pause =false;
/*		int action = getGameAction(keyCode);
		switch(action){
			case Canvas.UP:
				preposition();
				break;
			case Canvas.DOWN:
				nextposition();
				break;
		}*/
	}
	public void keyReleased(int keyCode){
		pause = true;
		gx = -999;
		stop(keyCode);
	}
	public synchronized void start(int keyCode) {
		this.keyCode[index] = (byte) keyCode;
		index = (byte) ((index + 1) % this.keyCode.length);
	}
	public synchronized void stop(int keyCode) {
		for ( int i = 0 ; i <= this.keyCode.length - 1 ; i++) {
			if ( this.keyCode[i] == (byte) keyCode) {
				this.keyCode[i] = 0;
				break;
			}
		}
}
//	public synchronized boolean getPressedPoint() {
//		isPressed = false;
//		for ( int i = 0 ; i <= keyCode.length - 1 ; i++) {
//			if ( this.keyCode[i] != 0) {
//				isPressed = true;
//				break;
//			}
//		}
//		return isPressed;
//	}
//	public void keyRepeated(int keyCode){
//		keyPressed(keyCode);
//	}
	public void moveStart(){
		if ( positionchange) {
			positionchange = false;
			int positionStart = 0;
			int positionEnd = 0;
			for ( int i = start, stop = children.size() ; i < stop && i < position ; i++) {
				positionStart += ((ScrollItem) children.elementAt(i)).height;
			}
System.out.println("start "+start);			
System.out.println("position "+position);
System.out.println("positionStart "+positionStart);
			positionEnd = positionStart + ((ScrollItem) children.elementAt(position)).height;
			if ( positionStart <= 0) {
				start = position;
			}
			else if ( positionEnd > height) {
				for ( int i = start ; i <= position && i < children.size() && positionEnd > height ; i++) {
					start++;
					positionEnd -= ((ScrollItem) children.elementAt(i)).height;
				}
			}
		}
	}
	protected void paint(Graphics g) {
		int x=0, y=0;
		g.setColor(0x00aa12);
		g.fillRect(0, 0, width, height);
		int[] clip = {g.getClipX(),g.getClipY(),g.getClipWidth(),g.getClipHeight()};
		g.setClip(x, y, width, height);
		
		if(!children.isEmpty()){
			if(isGameA&&isGameB){
				System.out.println("combine click"+isGameA +" "+isGameB);
				start =  0;position = 0;
				for(int i=start;i<children.size()&&y<height;i++){
					item = ((ScrollItem)children.elementAt(i));
					item.paint(g, x, y, width-scrollbarwidth, 23, i==position);
					y += item.height;
					
				}
			}
			else {
				moveStart();
				for ( int i = start ; i < children.size() && y < height ; i++) {
					item = ((ScrollItem) children.elementAt(i));
					item.paint(g, x, y, width - scrollbarwidth, 23, i == position);
					y += item.height;

				}
			}
			if(start>0 || y>height){
				double scrollbarheight = Math.floor((height+.5)/children.size());
				int scrollbary = (int) Math.floor(scrollbarheight*position+.5);
				g.setColor(0);
				g.fillRect(width-scrollbarwidth, scrollbary, scrollbarwidth, (int)scrollbarheight);
			}
		}
		g.setClip(clip[0], clip[1], clip[2], clip[3]);
	}
	public void run() {
		while(isKeepGoing){
			if(!pause){
				byte[] temp = keyCode;
				for ( int i = 0 ; i < temp.length ; i++) {
					if ( temp[i] != 0) {
						switch ( gx) {
							case Canvas.LEFT:
							case Canvas.UP:
								preposition();isGameA=false;isGameB=false;
								break;
							case Canvas.RIGHT:
							case Canvas.DOWN:
								nextposition();isGameA=false;isGameB=false;
								break;
//							case Canvas.GAME_A:
//								isGameA = true;
//								break;
//							case Canvas.GAME_B:
//								isGameB = true;
//								break;
//							default:isGameA=false;isGameB=false;break;
						}
						if(temp[i]==Canvas.KEY_NUM9){
							System.out.println("click 9");
							isGameA = true;
						}else
						if(temp[i]==Canvas.KEY_POUND){
							System.out.println("click #");
							isGameB = true;
						}else{
							isGameA=false;isGameB=false;
						}
					}
				}
				repaint();
			}
			try {
				Thread.sleep(70);
			}
			catch (InterruptedException e) {
			}
		}
	}
	
}