Java Piano模拟钢琴源码+编程思路

//Piano.java import java.applet.*; import java.awt.*; import java.awt.event.*; //Download by http://www.codefans.net public class Piano extends Applet implements MouseListener,KeyListener,MouseMotionListener { //变量声明 Image m_ImgUp;//键盘、鼠标松开时显示的键盘图片 Image m_ImgDown;//键盘、鼠标按下时显示的键盘图片 AudioClip[] m_AudioClip=new AudioClip[14]; int[] m_nState=new int[14]; int m_nOldDownCount=-1; final int IMG_WIDTH=17; final int IMG_HEIGHT=85; final int STATE_UP=0; final int STATE_DOWN=1; //初始化小程序 public void init() { for(int i=0;i<14;i++) { m_nState[i]=0; } m_ImgUp=getImage(getDocumentBase(),"img/up.gif"); m_ImgDown=getImage(getDocumentBase(),"img/down.gif"); MediaTracker mediaTracker=new MediaTracker(this); mediaTracker.addImage(m_ImgUp,0); mediaTracker.addImage(m_ImgDown,1); try { mediaTracker.waitForID(0); } catch(Exception e) { System.out.println("m_ImgUp is not loaded right"); } try { mediaTracker.waitForID(1); } catch(Exception e) { System.out.println("m_ImgDown is not loaded right"); } for(int i=0;i<14;i++) { String sUrl=new String("au/"+i+".au"); m_AudioClip[i]=getAudioClip(getCodeBase(),sUrl); } addKeyListener(this); addMouseListener(this); addMouseMotionListener(this); } //画屏函数 public void paint(Graphics g) { for(int i=0;i<14;i++) { switch(m_nState[i]) { case STATE_UP: g.drawImage(m_ImgUp,i*IMG_WIDTH,0,this); break; case STATE_DOWN: g.drawImage(m_ImgDown,i*IMG_WIDTH,0,this); break; } } } //主函数 public static void main(String[] args) { Frame frame=new Frame(); Piano piano=new Piano(); frame.add(piano); Dimension dimension=new Dimension(40,200); frame.setSize(dimension); frame.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); frame.setVisible(true); frame.repaint() ; } void showSound(int nCount) { m_AudioClip[nCount].play(); } //响应点击鼠标 public void mouseClicked(MouseEvent e) { int nMouseCount=e.getClickCount(); } //响应鼠标进入 public void mouseEntered(MouseEvent e) { } //响应鼠标退出 public void mouseExited(MouseEvent e) { if(m_nOldDownCount!=-1)m_nState[m_nOldDownCount]=STATE_UP; m_nOldDownCount=-1; } //响应按下鼠标 public void mousePressed(MouseEvent e) { int nX=e.getX(); int nY=e.getY(); int nCount=nX/IMG_WIDTH; m_nState[nCount]=STATE_DOWN; showSound(nCount); m_nOldDownCount=nCount; Graphics g=getGraphics(); g.drawImage(m_ImgDown,nCount*IMG_WIDTH,0,this); } //响应松开鼠标 public void mouseReleased(MouseEvent e) { int nX=e.getX(); int nY=e.getY(); int nCount=nX/IMG_WIDTH; m_nState[nCount]=STATE_UP; m_nOldDownCount=-1; Graphics g=getGraphics(); g.drawImage(m_ImgUp,nCount*IMG_WIDTH,0,this); } //响应按下键盘 public void keyPressed(KeyEvent e) { int nKeyCode=e.getKeyCode(); String sKeyName=e.getKeyText(nKeyCode); boolean bControlDown=e.isControlDown(); int nCount=-1; switch(nKeyCode) { case KeyEvent.VK_1: nCount=0; break; case KeyEvent.VK_2: nCount=1; break; case KeyEvent.VK_3: nCount=2; break; case KeyEvent.VK_4: nCount=3; break; case KeyEvent.VK_5: nCount=4; break; case KeyEvent.VK_6: nCount=5; break; case KeyEvent.VK_7: nCount=6; break; default: return; } if(bControlDown)nCount=nCount+7; setPianoKeyDown(nCount); showSound(nCount); Graphics g=getGraphics(); g.drawImage(m_ImgDown,nCount*IMG_WIDTH,0,this); } public void keyReleased(KeyEvent e) { int nKeyCode=e.getKeyCode(); String sKeyName=e.getKeyText(nKeyCode); boolean bControlDown=e.isControlDown(); int nCount=-1; switch(nKeyCode) { case KeyEvent.VK_1: nCount=0; break; case KeyEvent.VK_2: nCount=1; break; case KeyEvent.VK_3: nCount=2; break; case KeyEvent.VK_4: nCount=3; break; case KeyEvent.VK_5: nCount=4; break; case KeyEvent.VK_6: nCount=5; break; case KeyEvent.VK_7: nCount=6; break; default: return; } if(bControlDown)nCount=nCount+7; m_nState[nCount]=STATE_UP; Graphics g=getGraphics(); g.drawImage(m_ImgUp,nCount*IMG_WIDTH,0,this); } public void keyTyped(KeyEvent e) { } void setPianoKeyDown(int nCount) { for(int i=0;i<14;i++) { m_nState[i]=STATE_UP; } m_nState[nCount]=STATE_DOWN; } void setAllPianoKeyUp() { for(int i=0;i<14;i++) { m_nState[i]=STATE_UP; } } //响应拖动鼠标 public void mouseDragged(MouseEvent e) { int nX=e.getX(); int nY=e.getY(); System.out.println("鼠标拖动到：x="+nX+" y="+nY); int m_nTempCount=nX/IMG_WIDTH; if(m_nTempCount==m_nOldDownCount)return; m_nState[m_nTempCount]=STATE_DOWN; m_nState[m_nOldDownCount]=STATE_UP; showSound(m_nTempCount); Graphics g=getGraphics(); g.drawImage(m_ImgDown,m_nTempCount*IMG_WIDTH,0,this); g.drawImage(m_ImgUp,m_nOldDownCount*IMG_WIDTH,0,this); m_nOldDownCount=m_nTempCount; } //响应移动鼠标 public void mouseMoved(MouseEvent e) { int nX=e.getX(); int nY=e.getY(); System.out.println("鼠标移动到：x="+nX+" y="+nY); } }