JavaMe開發：低級界面繪圖之菜單(2)

KeyID.Java

package com.token.vIEw.components;  
 
public class KeyID {  
    public static final byte KEY_EDIT=-5;//選擇  
    public static final byte SOFT_LEFT=-6;//左軟鍵  
    public static final byte SOFT_RIGHT=-7;//右軟鍵  
      
    private KeyID(){  
    }  
}  

Menu.Java

package com.token.vIEw.components;  
 
import Javax.microedition.lcdui.*;  
import Javax.microedition.lcdui.game.*;  
public class Menu   
{  
     private String leftOption;  
     private String rightOption;  
     private String cancelOption = "取消";  
     private String okOption = "確定";  
     private String[] menuOptions;  
     private int padding;  
     private Font ft;  
     private int width;  
     private int height;  
     public int menuHeight;  
       
     public Menu(GameCanvas canvas)  
     {  
         width = canvas.getWidth();  
         height = canvas.getHeight();  
     }  
       
     public Menu(GameCanvas canvas, String leftOption, String rightOption, String[] menuOptions) {  
          this.leftOption = leftOption;  
          this.rightOption = rightOption;  
          this.menuOptions = menuOptions;  
              
          width = canvas.getWidth();  
          height = canvas.getHeight();  
     } // end constructor  
 
//繪制軟鍵選項  
    public void drawMenu(GameCanvas canvas, Graphics graphics, String leftOption, String rightOption)  
    {  
        width = canvas.getWidth();  
        height = canvas.getHeight();  
           
        padding = 5;  
        ft = Font.getFont(Font.FACE_PROPORTIONAL, Font.STYLE_BOLD,  
                Font.SIZE_LARGE);  
        int fontHeight = ft.getHeight();  
        menuHeight = fontHeight + 2 * padding;  
          
        graphics.setColor(Color.cmdSelectTop);  
        graphics.fillRect(0, height-menuHeight, width, menuHeight/2+1);  
        graphics.setColor(Color.cmdSelectBottom);  
        graphics.fillRect(0, height-menuHeight/2, width, menuHeight/2);  
          
        graphics.setFont(ft);  
        graphics.setColor(Color.label);  
          
        if(leftOption!=null)  
        {  
            graphics.drawString(leftOption, padding, height-padding, Graphics.LEFT | Graphics.BOTTOM);  
        }  
          
        if(rightOption!=null)  
        {  
            graphics.drawString(rightOption, width-padding, height-padding, Graphics.RIGHT | Graphics.BOTTOM);  
        }  
    }  
   
    public void drawSubMenu(Graphics graphics, int selectedOptionIndex)  
    {  
        padding = 6;  
        ft = Font.getFont(Font.FACE_PROPORTIONAL, Font.STYLE_BOLD,  
                Font.SIZE_MEDIUM);  
         int fontHeight = ft.getHeight();  
           
        //確定菜單的最大寬度、最大高度  
         int submenuMaxWidth = 0;  
         int submenuMaxHeight = 0;  
         int currentWidth = 0;  
           
         for (int i = 0; i < menuOptions.length; i++)   
         {  
            currentWidth = ft.stringWidth(menuOptions[i]);  
            if (currentWidth > submenuMaxWidth)   
            {  
                submenuMaxWidth = currentWidth;  
            }  
            submenuMaxHeight += fontHeight + padding;  
         }  
         submenuMaxWidth += 6 * padding;//5個padding用於顯示字符  
           
         int sub_padding = 3;  
         int sub_margin_left = 2;  
         int sub_margin_bottom = 2;  
           
         int submenuFrameMaxWidth = submenuMaxWidth + 2*sub_padding;  
         int submenuFrameMaxHeight = submenuMaxHeight + 2*sub_padding;  
 
         graphics.setColor(Color.menuFrame);  
         graphics.drawRoundRect(sub_margin_left, // x  
                 height - menuHeight - submenuFrameMaxHeight-sub_margin_bottom, // y  
                 submenuFrameMaxWidth, submenuFrameMaxHeight,5,5);  
         graphics.setColor(Color.menuBg);  
         graphics.fillRoundRect(sub_margin_left+1, // x  
                 height - menuHeight - submenuFrameMaxHeight-sub_margin_bottom+1, // y  
                 submenuFrameMaxWidth-1, submenuFrameMaxHeight-1,5,5);  
 
           
         graphics.setFont(ft);  
         int menuOptionX = sub_margin_left + sub_padding + padding;  
         int menuOptionY = height - menuHeight - submenuMaxHeight-sub_margin_bottom-sub_padding+padding/2;  
           
         for (int i = 0; i < menuOptions.length; i++)   
         {  
             if (i != selectedOptionIndex)   
             {  
                 // draw unselected menu option  
                 graphics.setColor(Color.text); // black  
                 graphics.drawString(menuOptions[i], menuOptionX, menuOptionY, Graphics.LEFT  
                   | Graphics.TOP);  
             }  
             else   
             {  
                 // draw selected menu option  
                 graphics.setColor(Color.selectBg);  
                 int highOptionY=height - menuHeight - sub_margin_bottom - submenuMaxHeight + i*(fontHeight + padding)-sub_padding;  
                 graphics.fillRect(sub_margin_left+sub_padding,highOptionY,submenuMaxWidth+1,fontHeight + padding);  
                 graphics.setColor(Color.selectText);  
                 graphics.drawString(menuOptions[i], menuOptionX, menuOptionY, Graphics.LEFT  
                   | Graphics.TOP);  
             }   
             menuOptionY += padding + fontHeight;  
         }  
    }  
      
    public void drawInactiveMenu(GameCanvas canvas, Graphics graphics)   
    {  
      drawMenu(canvas, graphics,leftOption,rightOption);  
      canvas.flushGraphics();  
    } // end drawInactiveMenu  
      
     public void drawActiveMenu(GameCanvas canvas, Graphics graphics, int selectedOptionIndex)   
     {  
         drawMenu(canvas, graphics,cancelOption,okOption);  
         // draw menu options  
         if (menuOptions != null)   
         {  
             drawSubMenu(graphics,selectedOptionIndex);  
             canvas.flushGraphics();  
        }  
     }  
} 

MainScreen.Java(程序有刪減，僅供學習交流)

package com.token.vIEw;  
 
import Javax.microedition.lcdui.*;  
import Javax.microedition.lcdui.game.GameCanvas;  
 
import com.token.util.*;  
import com.token.vIEw.components.*;  
 
public class MainScreen extends GameCanvas   
{  
 
    private UIController controller;  
    private Font ft;  
    private int width;  
    private int height;  
      
    static final String[] menuOptions = { "1.查看","2.更新","3.用戶管理","4.幫助","5.換膚","6.退出" };   
      
    static int menuIdx;// 記錄是在第幾個菜單處按下的確定鍵。     
    private int currentlySelectedIndex = 0;     
    private boolean menuIsActive = false;     
    private String leftOption;     
    private String rightOption;     
    private Graphics graphics;     
    private Menu menu;  
      
    public MainScreen(UIController control)  
    {  
        super(false);  
        this.controller = control;  
        setFullScreenMode(true);  
          
        ft = Font.getFont(Font.FACE_PROPORTIONAL,Font.STYLE_BOLD,Font.SIZE_LARGE);  
          
        width = getWidth();  
        height = getHeight();  
          
        graphics = getGraphics();  
        menuIdx = 0;  
          
        leftOption = "選項";     
        rightOption = "";     
          
        menu = new Menu(this, leftOption, rightOption, menuOptions);  
    }  
      
    public void show(Object[] args) {     
          
        draw();  
        //flushGraphics();  
    }   
      
    private void draw()  
    {  
        menu.drawInactiveMenu(this, graphics);  
    }  
      
    public void drawBase()  
    {  
        //clearScreen();  
    }  
      
 
    public void clearScreen()  
    {  
        graphics.setColor(0xff,0xff,0xff);  
        graphics.fillRect(0, 0, width, height);  
        flushGraphics();  
    }  
 
    protected void keyPressed(int keyCode)   
    {  
          if (menuIsActive)  
          {  
               if (keyCode == KeyID.SOFT_LEFT)   
               {  
                // cancel pressed, draw inactive menu again  
                drawBase();  
                menu.drawInactiveMenu(this, graphics);  
                menuIsActive = false;  
               }  
                 
               switch(keyCode)  
               {  
                   case KEY_NUM1:  
                       currentlySelectedIndex = 0;  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                   case KEY_NUM2:  
                       currentlySelectedIndex = 1;  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                   case KEY_NUM3:  
                       currentlySelectedIndex = 2;  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                   case KEY_NUM4:  
                       currentlySelectedIndex = 3;  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                 case KEY_NUM5:  
                       currentlySelectedIndex = 4;  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                case KEY_NUM6:  
                       currentlySelectedIndex = 5;  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                case KeyID.SOFT_RIGHT:  
                       keyCode = FIRE;  
                       break;  
                   default:;  
               }  
               
               keyCode = (keyCode != FIRE)?getGameAction(keyCode):keyCode;  
                 
               switch(keyCode)  
               {  
                   case UP:   
                        if(currentlySelectedIndex==0)  
                        {  
                            currentlySelectedIndex = menuOptions.length-1;  
                        }  
                        else 
                        {  
                            currentlySelectedIndex--;  
                            if (currentlySelectedIndex < 0)   
                            {  
                             currentlySelectedIndex = 0; // stay within limits  
                            }   
                        }  
                        menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                         
                        break;  
                   case DOWN:  
                       if(currentlySelectedIndex==menuOptions.length-1)  
                       {  
                         currentlySelectedIndex = 0;  
                       }  
                       else 
                       {  
                           currentlySelectedIndex++;  
                           if (currentlySelectedIndex >= menuOptions.length)  
                           {  
                               currentlySelectedIndex = menuOptions.length - 1;  
                           }  
                       }  
                       menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                       break;  
                   case FIRE:   
                   {  
                       drawBase();  
                       graphics.setColor(0x000000);  
                       menu.drawInactiveMenu(this, graphics);  
                       menuIsActive = false;  
                       //按鍵處理  
                       switch(currentlySelectedIndex)  
                       {  
                           case 0:  
                           {  
                               //Object []args = {"vIEwScreen", "userAuth_name",null,null};  
                               //controller.handleEvent(UIController.EventID.EVENT_VIEW_AUTH,args);  
                               break;  
                           }  
                           case 1:  
                           {  
                               //Object []args = {"updateScreen", "userAuth_name",null,null};  
                               //controller.handleEvent(UIController.EventID.EVENT_UPDATE_AUTH, args);  
                               break;  
                           }  
                           case 2:  
                           {  
                               //Object []args = {"manageScreen", "userAuth_name",null,null};  
                               //controller.handleEvent(UIController.EventID.EVENT_USER_MANAGE_AUTH, args);  
                               break;  
                           }  
                           case 3:  
                           {  
                              //controller.handleEvent(UIController.EventID.EVENT_SHOW_HELP,null);  
                               break;  
                           }  
                           case 4:  
                           {  
                               break;  
                           }  
                           case 5:  
                           {  
                               //controller.handleEvent(UIController.EventID.EVENT_EXIT,null);  
                               break;  
                           }  
                           default:;  
                       }  
                       break;  
                   }  
                   default:;  
               }  
          }  
          else   
          {  
              if (keyCode == KeyID.SOFT_LEFT)   
              { // "Options" pressed  
                  menu.drawActiveMenu(this, graphics, currentlySelectedIndex);  
                  menuIsActive = true;  
              }  
              else if (keyCode == KeyID.SOFT_RIGHT)   
              {  
 
              }  
          }  
     }  
}  

*關於UIController，後續文章將給予解釋。