www.pudn.com > ¼ÆËãÆ÷java.rar > ButtonComponent.java

/** 
* File:  		ButtonComponent.java 
* Description:  A Button component that feature's three a dimensional 
*				similar to swing components. 
*/ 
 
import java.lang.*; 
import java.util.*; 
import java.awt.*; 
import java.awt.event.*; 
 
public class ButtonComponent extends Component { 
 
    private String label;                 //the button's label 
    private boolean pressed = false;	  //used to determine button presses 
    private ActionListener action;		   
    private boolean mouseOver = false;    //used to determine mouse overs  
    private Border3D border;			  //to draw a 3D border around button 
   
public ButtonComponent(String label) 
{ 
    this.label = label; 
    border = new Border3D( this );     
    enableEvents(AWTEvent.MOUSE_EVENT_MASK); 
} 
   
     
/** 
* Returns the preferred size of the button. This method is called automatically 
* when the component is painted. 
* 
*/ 
public Dimension getPreferredSize()  
{ 
    Font f = getFont(); 
    if(f != null) { 
       FontMetrics fm = getFontMetrics(getFont()); 
       return new Dimension(fm.stringWidth(label) + 10, fm.getHeight() + 5); 
    }  
    else { 
       return new Dimension(25, 25); 
    } 
} 
   
/** 
* Returns the minimum size of the button.  
*/ 
public Dimension getMinimumSize() { return new Dimension(20, 20); } 
    
/** 
* Detects mouse events on the component. 
*/ 
public void processMouseEvent(MouseEvent e)  
{   
    switch(e.getID()) { 
    	 
      case MouseEvent.MOUSE_PRESSED: 
         
        //Create a new actionevent and pass to the action listener - 
        //( the Button Handler ) 
           
        if ( action != null ) {             
             ActionEvent event = new ActionEvent( this, e.getID(), label ); 
             action.actionPerformed( event ); 
        } 
         
        pressed = true;                     
         
        //Invoke the repaint method which draws the button to appear pressed     
        repaint();  
        break; 
         
      case MouseEvent.MOUSE_RELEASED: 
        //When repaint is invoked, component color is returned to normal    
        if(pressed == true) { 
           pressed = false; 
           repaint(); 
         } 
         break; 
          
      case MouseEvent.MOUSE_ENTERED: 
         //repaint method lighten's component's color to give a hover effect  
         mouseOver = true; 
         repaint(); 
         break; 
          
      case MouseEvent.MOUSE_EXITED: 
          
         //cancel hover effect 
         mouseOver = false; 
         if(pressed == true) pressed = false;                
             
         repaint(); 
         break; 
       } 
        
    super.processMouseEvent(e); 
} 
 
//Add's action listener    
public void addActionListener( ActionListener a ) 
{ 
	action = a;    //this is the ButtonHandler 
} 
  
//returns the buttons label   
public String getLabel() { return label; } 
 
/* 
* repaints the background 
*/ 
public void paint(Graphics g) { 
    int width = getSize().width - 1; 
    int height = getSize().height - 1; 
       
    //set background darker to give a pressed effect 
    if(pressed) { 
       g.setColor(getBackground().darker().darker()); 
    }  
    //set background lighter to give hover effect 
    else if ( mouseOver ) { 
       g.setColor( getBackground().brighter() );  
     
    //set background to normal     
    } else { 
       g.setColor(getBackground()); 
    } 
     
    //fill background                           
    g.fillRect(0, 0, width, height );   
     
    //draws 3D border 
    border.draw3DBorder(g, 0, 0, width, height ); 
     
    //center and draw the button's label         		     
    Font f = getFont(); 
    if(f != null) { 
       FontMetrics fm = getFontMetrics(getFont()); 
       g.setColor(getForeground()); 
       g.drawString(label, 
                    width/2 - fm.stringWidth(label)/2, 
                    height/2 + fm.getMaxDescent()); 
    } 
} 
 
}