File	Doc	Category	Size	Date	Package
Screen.java	API Doc	J2ME MIDP 2.0	10184	Thu Nov 07 12:02:28 GMT 2002	javax.microedition.lcdui

Screen

• java.lang.Object
  • Displayable

Fields Summary
static final Font	CONTENT_FONT Special content font, shared amongst the LCDUI package
static final int	CONTENT_HEIGHT Special content height, shared amongst the LCDUI package
int	paintBorder When paintBorder is not BORDER_NONE, there is a pixel border painted around content and viewPort is reduced by 4 pixels. This is used by subclasses such as TextBox which need a pixel border around them.
static final int	BORDER_NONE this is for no border
static final int	BORDER_SOLID this is for a solid border
static final int	BORDER_GRAY this is for a dotted light grey border
static final boolean	SCROLLS_HORIZONTAL A boolean declaring whether the viewport is capable of scrolling horizontally. FALSE by default
static final boolean	SCROLLS_VERTICAL A boolean declaring whether the viewport is capable of scrolling vertically. TRUE by default
int[]	view An array which holds the scroll location and the overall dimensions of the view being shown in the parent Displayable's viewport Note that the following is always true. 0 <= view[X] <= view[WIDTH] - viewport[WIDTH] 0 <= view[Y] <= view[HEIGHT] - viewport[HEIGHT]
boolean	resetToTop Screens should automatically reset to the top of the when they are shown, except in cases where it is interrupted by a system menu or an off-screen editor - in which case it should be reshown exactly as it was.

Constructors Summary
Screen() Creates a new Screen object with no title and no ticker. // ************************************************************ // private member variables // ************************************************************ // ************************************************************ // Static initializer, constructor // ************************************************************ this(null);
Screen(String title) Creates a new Screen object with the given title and with no ticker. param title the Screen's title, or null for no title view = new int[4]; view[X] = 0; view[Y] = 0; view[WIDTH] = 0; view[HEIGHT] = 0; super.setTitleImpl(title);

Methods Summary
void	callPaint(Graphics g, java.lang.Object target) Paint the contents of this Screen param g the Graphics to paint to param target the target Object of this repaint super.callPaint(g, target); /* System.err.println("Screen:Clip: " + g.getClipX() + "," + g.getClipY() + "," + g.getClipWidth() + "," + g.getClipHeight()); */ synchronized (Display.LCDUILock) { if ((paintBorder != BORDER_NONE) && (g.getClipX() < viewport[X])) { // erase the border and its surrounding rectangles g.setColor(Display.ERASE_COLOR); g.drawRect(viewport[X] - 4, viewport[Y] - 4, viewport[WIDTH] + 7, viewport[HEIGHT] + 7); g.drawRect(viewport[X] - 3, viewport[Y] - 3, viewport[WIDTH] + 5, viewport[HEIGHT] + 5); g.drawRect(viewport[X] - 2, viewport[Y] - 2, viewport[WIDTH] + 3, viewport[HEIGHT] + 3); g.drawRect(viewport[X] - 1, viewport[Y] - 1, viewport[WIDTH] + 1, viewport[HEIGHT] + 1); // Draw the border if (paintBorder == BORDER_SOLID) { // solid border g.setColor(Display.FG_COLOR); } else { // light gray dotted border g.setColor(Display.BORDER_COLOR); g.setStrokeStyle(Graphics.DOTTED); } g.drawRect(viewport[X] - 3, viewport[Y] - 3, viewport[WIDTH] + 5, viewport[HEIGHT] + 5); // restore the line style g.setStrokeStyle(Graphics.SOLID); } // Clip off the ticker/title area to keep subclasses from // painting on it g.clipRect(viewport[X], viewport[Y], viewport[WIDTH], viewport[HEIGHT]); if (target == null || ( target instanceof Item && ((Item)target).owner == this)) { g.setColor(Display.ERASE_COLOR); g.fillRect(g.getClipX(), g.getClipY(), g.getClipWidth(), g.getClipHeight()); g.setColor(Display.FG_COLOR); } } // synchronized
void	layout() Layout the contents of this screen. Calls super.layout() and then translateViewport(); super.layout(); translateViewport();
void	repaintItem(Item item, int x, int y, int w, int h) Paint an Item contained in this Screen. The Item requests a paint in its own coordinate space. Screen translates those coordinates into the overall coordinate space and schedules the repaint param item the Item requesting the repaint param x the x-coordinate of the origin of the dirty region param y the y-coordinate of the origin of the dirty region param w the width of the dirty region param h the height of the dirty region callRepaint(item.bounds[X] + viewport[X] - view[X] + x, item.bounds[Y] + viewport[Y] - view[Y] + y, w, h, item);
void	setVerticalScroll() Set the vertical scroll indicators for this Screen // Previously, Screen was always resetting the left/right // scroll indicators to 0 when it set the up/down indicators, // now it sets the up/down indicators as appropriate, but // maintains the left/right indicators as they were, and it // is the component's responsibility (ie Gauge) to update // the right/left scroll indicators if necessary if (view[HEIGHT] <= viewport[HEIGHT]) { super.setVerticalScroll(0, 100); } else { super.setVerticalScroll( (view[Y] * 100 / (view[HEIGHT] - viewport[HEIGHT])), (viewport[HEIGHT] * 100 / view[HEIGHT])); }
private void	translateViewport() Translate the viewport[] array so that subclasses only render within the viewport if (paintBorder != BORDER_NONE) { // translate the viewport for subclasses layout() // to utilize viewport[X] += 4; viewport[Y] += 4; viewport[WIDTH] -= 8; viewport[HEIGHT] -= 8; }