[移动图书馆]在手持设备上一步一步实现Table(1)

/*
 * TableModel.java
 *
 * Created on 2006年7月2日, 下午3:53
 *
 * To change this template, choose Tools | Options and locate the template under
 * the Source Creation and Management node. Right-click the template and choose
 * Open. You can then make changes to the template in the Source Editor.
 */

package cn.edu.uestc.table;

    /**
     * <P>Returns the number of rows the model contains.
     */
    public int getRowCount();

    /**
     * <P>Returns the text for the column header.
     */
    public String getColumnHeaderText(int col);

    /**
     * <P>Returns whether column headers are displayed.
     */
    public boolean hasColumnHeaders();

    /**
     * <P>Returns the value for the specified cell.
     */
    public String getValueAt(int row,int col);
   
}

/*
 * Table.java
 *
 * Created on 2006年7月2日, 下午3:55
 *
 * To change this template, choose Tools | Options and locate the template under
 * the Source Creation and Management node. Right-click the template and choose
 * Open. You can then make changes to the template in the Source Editor.
 */

package cn.edu.uestc.table;
import javax.microedition.lcdui.*;
/**
 *
 * @author pandaxiaoxi
 */

public class Table extends Canvas {
    public static final int ORIENT_VERTICAL   = 0;
    public static final int ORIENT_HORIZONTAL = 1;

    private TableModel model         = null;
    private Font       font           = Font.getDefaultFont();
    private int        columnWidth    = 85;
    private int        orientation    = ORIENT_VERTICAL;   //每列竖直显示
    private boolean    separatorLines = true;
  
    /**
     * <P>Creates an instance with the associated model.
     */
    public Table(TableModel model) {
            if(null == model) {
                      throw new IllegalArgumentException("Cannot pass a null model to a table");
             }

            this.model = model;
    }
    public Table(){
       
    }
    public void setTableModel(TableModel model){
        if(null == model) {
                   throw new IllegalArgumentException("Cannot pass a null model to a table");
        }
        this.model = model;
    }
    /**
     * <P>Sets the column width
     */
    public void setColumnWidth(int width) {
           if(0 < width) {
                columnWidth = width;
            }
    }

    /**
     * <P>Returns the column width.
     */
    public int getColumnWidth() {
             return columnWidth;
    }

    /**
     * <P>Sets the table orientation.
     *
     * @param orient either <CODE>ORIENT_VERTICAL</CODE> or <CODE>ORIENT_HORIZONTAL</CODE>
     */
    public void setOrientation(int orient) {
             switch(orient) {
                   case ORIENT_VERTICAL:
                  case ORIENT_HORIZONTAL:
                      orientation = orient;
                      break;
                  default:
                      System.out.println("Invalid orientation!");
                      break;
             }
    }

    /**
     * <P>Returns the table orientation.
     */
    public int getOrientation() {
             return orientation;
    }
   
    /**
     * <P>Toggles whether separator lines are used between rows and between columns.
     */
    public void setSeparatorLines(boolean sep) {
             separatorLines = sep;
    }

    /**
     * <P>Returns whether separator lines are used.
     */
    public boolean getSeparatorLines() {
            return separatorLines;
    }

    public void paint(Graphics g) {
           int width = getFullWidth(), height = getFullHeight();

 // clear the background
 g.setColor(255,255,255);
 g.fillRect(0,0,width,height);
 g.setColor(0,0,0);

 // draw the border for the table
 g.drawRect(0,0,width,height);
       
 if(separatorLines) {
     int vbars = 0;
     int hbars = 0;

     // determine how many vertical and horizontal bars to draw
     switch(orientation) {
     case ORIENT_VERTICAL:
  vbars = model.getColumnCount();
  hbars = model.getRowCount();
  if(model.hasColumnHeaders()) hbars++;
  break;

     case ORIENT_HORIZONTAL:
  vbars = model.getRowCount();
  hbars = model.getColumnCount();
  if(model.hasColumnHeaders()) vbars++;
  break;
     }
            boolean flag = false;
           
     // draw horizontal row with different color
     for(int index = 0;index < hbars;index++) {
  int y = index * getVerticalSpacing();
  if(index == 0){
                    g.setColor(152, 152, 152);
                    g.fillRect(0,y, width-1,getVerticalSpacing());
                    continue;
                }
                   
                if(flag){
                    g.setColor(215,215,215);
                    flag = false;
                }else{
                    g.setColor(255,255,255);
                    flag = true;
                }
                g.fillRect(0,y, width-1,getVerticalSpacing());
            }
            g.setColor(70,95,182);
           
            g.setColor(0,0,0);  
            // draw horizontal bars
     for(int index = 0;index < hbars;index++) {
  int y = index * getVerticalSpacing();
  g.drawLine(0,y,width - 1,y);
               
            }
             // draw vertical bars
     for(int index = 0;index < vbars;index++) {
  //int x = index * getHorizontalSpacing();
                int x = index * columnWidth;
  g.drawLine(x,0,x,height - 1);
               
     }
           
 }
       
 int rowOffset = 0; // used to flag whether headers are displayed

 // if using column headers, let's show them first
 if(model.hasColumnHeaders()) {
     for(int col = 0;col < model.getColumnCount();col++) {
  // the row should be -1 for this call
  drawTableCell(g,0,col,model.getColumnHeaderText(col));
     }
     // set the row offset
     rowOffset = 1;
 }
       
       
 // now draw each element of the table
 for(int row = 0;row < model.getRowCount();row++) {
     for(int col = 0;col < model.getColumnCount();col++) {
  String value = model.getValueAt(row,col);
  // now use the rowOffset to adjust if column headers were used
  drawTableCell(g,row + rowOffset,col,value);
     }
 }
       
    }

    private void drawTableCell(Graphics g,int row,int col,String value) {
 int valueSize = columnWidth - 4; // to make sure it fits in a column space
 if(0 < valueSize) {
     while(valueSize < font.stringWidth(value)) {
  value = value.substring(0,value.length() - 1);
  // if the string is now empty, just exit... we can't display it...
  if(0 == value.length()) {
      return;
  }
     }

     int x = getXFor(row,col) + 1;
     int y = getYFor(row,col) + 2;
    
     g.drawString(value,x,y,Graphics.LEFT | Graphics.TOP);
 }
    }

    private int getXFor(int row,int col) {
 if(ORIENT_VERTICAL == orientation) {
     return col * getHorizontalSpacing();
 } else {
     return row * getHorizontalSpacing();
 }
    }

    private int getYFor(int row,int col) {
 if(ORIENT_VERTICAL == orientation) {
     return row * getVerticalSpacing();
 } else {
     return col * getVerticalSpacing();
 }
    }

    private int getVerticalSpacing() {
 return font.getHeight() + 3; // font height + 1 line above + 1 line below + 1 line for separator
    }

    private int getHorizontalSpacing() {
 int rightBorder = getFullWidth() - 1;

 if(ORIENT_VERTICAL == orientation) {
     return rightBorder / model.getColumnCount();
 } else {
     return rightBorder / model.getRowCount();
 }
    }

    // Scrollable interface

    public int getFullWidth() {
 int count = 0;
 if(ORIENT_VERTICAL == orientation) {
     count = model.getColumnCount();
 } else {
     count = model.getRowCount();
     if(model.hasColumnHeaders()) count++;
 }
 return (count * columnWidth) + 1;
    }

    public int getFullHeight() {
 int count = 0;

 if(ORIENT_VERTICAL == orientation) {
     count = model.getRowCount();
     if(model.hasColumnHeaders()) count++;
 } else {
     count = model.getColumnCount();
 }

 return (getVerticalSpacing() * count) + 1;
    }

    public int getVerticalScrollAmount() {
 return getVerticalSpacing();
    }

    public int getHorizontalScrollAmount() {
 return getHorizontalSpacing();
    }

    public void render(Graphics g) {
 paint(g);
    }

}

/*
 * TableDemo.java
 *
 * Created on 2006年7月2日, 下午3:59
 */

package cn.edu.uestc.table;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

/**
 *
 * @author  pandaxiaoxi
 * @version
 */
public class TableDemo extends MIDlet {
    private Display display = null;
    public void startApp() {
        display = Display.getDisplay(this);
        Table table = new Table(new TableModel(){
            public int getColumnCount(){return 3;}
            public int getRowCount(){return 5;}
            public String getColumnHeaderText(int col){return Integer.toString(col)+"列";}
            public boolean hasColumnHeaders(){return true;}
            public String getValueAt(int row,int col){return Integer.toString(row)+"."+Integer.toString(col);}
                     
        });
        display.setCurrent(table);
    }
   
    public void pauseApp() {
    }
   
    public void destroyApp(boolean unconditional) {
    }
}