panel.java

FIRE (Flexible Interface Rendering Engine)是一个J2ME上的灵活的图形界面引擎

		if (navbarSize == 0)
			return;

		if (navbarImage == null)
		{
			navbarImage = theme.getNavbarTexture(width, navbarSize);
		}
		if(navbarImage!=null)
		g.drawImage(navbarImage, 0, height - navbarSize, Graphics.TOP | Graphics.LEFT);
	}

	private void drawDecorLeft(Graphics g)
	{
		// decor left not supported by this panel implementation.
	}

	private void drawDecorRight(Graphics g)
	{
		// decor right not supported by this panel implementation.
	}

	public void validate()
	{
		theme = FireScreen.getTheme();
		if(showDecorations)
		{
			decorLeft = theme.decorLeft;
			titlebarSize = theme.decorTop;
			navbarSize = theme.decorBottom;
			decorRight = theme.decorRight;
		}
		else
		{
			decorLeft=0;
			titlebarSize=0;
			navbarSize=0;
			decorRight=0;
		}
		
		navbarImage = null;
		titlebarImage = null;

		int[] d = getPrefSize();
		if (d == null)
		{
			d = getMinSize();
		}
		width = d[0];
		height = d[1];


		if (container == null)
		{
			valid = true;
			return;
		}
		
		viewPortHeight = height - navbarSize - titlebarSize;
		viewPortWidth = width - decorLeft - decorRight;
		
		int []ps = container.getPrefSize();
		if(ps!=null) // a container inside a panel must be atleast the size of the viewport
		{
			if(ps[0]<viewPortWidth) ps[0] = viewPortWidth;
			if(ps[1]<viewPortHeight) ps[1] = viewPortHeight;
			container.setPrefSize(ps[0],ps[1]);
		}
		
		container.validate(); // validate the container

		container.x = decorLeft;
		container.y = titlebarSize;

		normalVScrollLength = (NORMAL_SCROLL_PERCENT*viewPortHeight)/100;
		normalHScrollLength = (NORMAL_SCROLL_PERCENT*viewPortWidth)/100;
		fastVScrollLength = (FAST_SCROLL_PERCENT*viewPortHeight)/100;
		fastHScrollLength = (FAST_SCROLL_PERCENT*viewPortWidth)/100;
		
		valid = true;
	}

	/**
	 * A Panel can have at most one container at any given time.
	 * 
	 * @param container
	 */
	public void set(Container container)
	{
		if(container==null) throw new IllegalArgumentException("Cannot set a null container to a Panel. Use remove() instead.");
		if (this.container != null)
			this.container.parent = null;

		this.container = container;
		
		if (container.parent != null)
		{
			if (container.parent instanceof Container)
				((Container) container.parent).remove(container);
		}
		container.parent = this;
		valid = false;
	}
	
	public Component getComponent(int i)
	{
		if(i==0)
			return container;
		else throw new ArrayIndexOutOfBoundsException("A panel has at most one container on index 0.");
	}
	
	public boolean remove(Component c)
	{
		if (container != c)
		{
			throw new IllegalArgumentException("Container "+c+" is not inside this panel.");
		}
		else if(container!=null)
		{
			container.parent = null;
			if(container.animation!=null) FireScreen.getScreen().removeAnimation(container.animation);
			container = null;
			valid = false;
			return true;
		}
		return false;
	}
	
	public int countComponents()
	{
		if(container!=null)
			return container.countComponents();
		else return 0;
	}
	
	

	/**
	 * 
	 * Sets the viewport position relative to the top left corner of the
	 * container inside this panel.
	 * 
	 * 
	 * @param x
	 *            the distance (in pixels) of the left side of the viewport from
	 *            the left side of the container
	 * @param y
	 *            the distance (in pixels) of the top side of the viewport from
	 *            the top side of the container
	 */
	public boolean setViewPortPosition(int x, int y)
	{
		if (container == null)
			return false;

		int tx = decorLeft - container.x;
		int ty = titlebarSize - container.y;


		if (x + viewPortWidth > container.width)
			x = container.width - viewPortWidth;
		else if (x < 0)
			x = 0;
		if (y + viewPortHeight > container.height)
			y = container.height - viewPortHeight;
		else if (y < 0)
			y = 0;
		
		if(x==tx && y==ty) // nothing changed return false
		{
			return false;
		}
		
		// ok now set the correct offset to the container.
		container.x = decorLeft - x;
		container.y = titlebarSize - y;
		repaint();
		return true; // change in the viewport position was successfull. 
	}

	/**
	 * Returns the vertical (X) coordinate of the viewport inside the innner container.
	 * @return
	 */
	public int getViewPortPositionX()
	{
		if (container == null)
			return 0;

		return decorLeft - container.x;
	}

	/**
	 * Returns the horizontal (Y) coordinate of the viewport inside the inner container.
	 * @return
	 */
	public int getViewPortPositionY()
	{
		if (container == null)
			return 0;
		return titlebarSize - container.y;
	}

	/**
	 * Returns the width of the viewport of this panel.
	 * @return
	 */
	public int getViewPortWidth()
	{
		return viewPortWidth;
	}
	
	/**
	 * Returns the height of the viewport of this panel.
	 * @return
	 */
	public int getViewPortHeight()
	{
		return viewPortHeight;
	}

	protected void pointerDragged(int x, int y)
	{
		if (container != null)
		{
			if(dragScroll && dragX==-1 && dragY==-1) // intercept drag events end use them for navigation.
			{ // keep the starting drag point. when the pointer is released a pointer event will be sent.
				dragX = x;
				dragY = y;
			}
			else if (x > decorLeft && x < width - decorRight && y > titlebarSize && y < height - navbarSize)
			{
				container.pointerDragged(x - container.x, y - container.y); 
			}
		}
		super.pointerDragged(x,y);
	}

	protected void pointerPressed(int x, int y)
	{
		if (container != null)
		{
			if (x > decorLeft && x < width - decorRight && y > titlebarSize && y < height - navbarSize)
			{
				container.pointerPressed(x - container.x, y - container.y);
			}
		}
		super.pointerPressed(x,y);
	}

	protected void pointerReleased(int x, int y)
	{
		if(closeOnOutofBoundsPointerEvents && (x<0 || x>width || y<0 || y>height)) FireScreen.getScreen().removeComponent(this);
		
		if(container != null)
		{
			int dx = 0;
			int dy = 0;
			if(dragX!=-1 && dragY!=-1){
				dx = x - dragX;
				dy = y - dragY;
			}
			if(dragScroll && (dx>10 || dx<-10 || dy>10 || dy<-10))
			{ // drag event.
				dx = x - dragX;
				dy = y - dragY;
				
				dragX=-1;dragY=-1;
				if(animation==null)
				{
					if(dy<-10) scrollVertically(fastVScrollLength);
					else if(dy>10) scrollVertically(-fastVScrollLength);
					else if(dx<-10) scrollHorizontally(fastHScrollLength);
					else if(dx>10) scrollHorizontally(-fastHScrollLength);
				}
			}
			else//If there is not a big dx or dy fire the event
			{
				int rightMargin = decorRight;
				if((scrollBarPolicy & VERTICAL_SCROLLBAR) == VERTICAL_SCROLLBAR && rightMargin<2*theme.scrollSize)
				{
					rightMargin = 2*theme.scrollSize;
				}
				
				if (x > decorLeft && x < width - rightMargin && y > titlebarSize && y < height - navbarSize)
				{
					container.pointerReleased(x - container.x, y - container.y);
				}
				else
				{
					if (((scrollBarPolicy & VERTICAL_SCROLLBAR) == VERTICAL_SCROLLBAR) && x > width - rightMargin && y < height - navbarSize)
					{ // check if click is on scrollbar
						if (y > scrollY ) // scroll down
						{
							scrollVertically(normalVScrollLength);
						} else
							// scroll up
						{
							scrollVertically(-normalVScrollLength);
						}
					} else if (((scrollBarPolicy & HORIZONTAL_SCROLLBAR) == HORIZONTAL_SCROLLBAR) && y > (height - navbarSize-theme.scrollSize) && y < height - navbarSize + theme.scrollSize)
					{
						if (x > scrollX)
						{
							scrollHorizontally(-normalHScrollLength);
						} else
						{
							scrollHorizontally(normalHScrollLength);
						}
					}
				}
			}
		}
		if(pointerListener!=null) pointerListener.pointerReleased(x,y,this);
	}

	/**
	 * Utility method to move the viewport vertically by the given number of pixels.
	 * If the number is negative the panel will scroll up, otherwise if will scroll down.
	 * @param pixels
	 */
	public void scrollVertically(int pixels)
	{
		if ((scrollBarPolicy & VERTICAL_SCROLLBAR) != VERTICAL_SCROLLBAR)
			return;
		int vpx = getViewPortPositionX();
		int vpy = getViewPortPositionY();
		setViewPortPosition(vpx,vpy+pixels);
		
		FireScreen screen = FireScreen.getScreen();
		if(this.animation==null && screen.isAnimationsEnabled()) //only animate scroll if there is no other animation running on this panel.
		{
			ScrollAnimation anim = new ScrollAnimation(this,vpx,vpy,vpx,vpy+pixels);
			screen.registerAnimation(anim);			
		}
	}

	/**
	 * Utility method to move the viewport horizontally by the given number of pixels.
	 * If the number is negative the panel will scroll right, otherwise if will scroll left.
	 * @param pixels
	 */
	public void scrollHorizontally(int pixels)
	{
		if ((scrollBarPolicy & HORIZONTAL_SCROLLBAR) != HORIZONTAL_SCROLLBAR)
			return;
		int vpx = getViewPortPositionX();
		int vpy = getViewPortPositionY();
		setViewPortPosition(vpx+pixels,vpy);
		
		FireScreen screen = FireScreen.getScreen();
		if(this.animation==null && screen.isAnimationsEnabled()) //only animate scroll if there is no other animation running on this panel.
		{
			ScrollAnimation anim = new ScrollAnimation(this,vpx,vpy,vpx+pixels,vpy);
			screen.registerAnimation(anim);			
		}
	}

	protected void keyPressed(int keyCode)
	{
		if (container != null)
			container.keyPressed(keyCode);

		if(keyListener!=null) keyListener.keyPressed(keyCode,this);
	}