Blackberry下实现文字滚动效果

LabelField testLabel = new LabelField(			"I swear to god up in the sky I will be your shelter when you cry Cause you are my everything.",			Field.FOCUSABLE) {		int currentChar = 0;		String currentText = null;		Font ourFont;		private Timer _scrollTimer;		private TimerTask _scrollTimerTask;		protected void paint(Graphics graphics) {			currentText = this.getText();			if (currentChar < currentText.length()) {				currentText = currentText.substring(currentChar);			}			graphics.drawText(currentText, 0, 0, DrawStyle.ELLIPSIS, Display					.getWidth());		}		protected void layout(int width, int height)  {			ourFont = this.getFont();			setExtent(Display.getWidth(), ourFont.getHeight());		}		protected void onDisplay() {			startScroll();		}		protected void onUnfocus() {			startScroll();		}		private void startScroll() {			// Start scrolling			final String fullText = this.getText();			if (_scrollTimer == null) {				_scrollTimer = new Timer();				_scrollTimerTask = new TimerTask() {					public void run() {						currentChar = currentChar + 4;						if (currentChar > fullText.length()) {							currentChar = 0;						}						invalidate();					}				};				_scrollTimer.scheduleAtFixedRate(_scrollTimerTask, 500, 500);			}		}		protected void onFocus(int direction) {			if (_scrollTimer != null) {				_scrollTimerTask.cancel();				_scrollTimer.cancel();				_scrollTimer = null;				_scrollTimerTask = null;			}		}		protected boolean navigationMovement(int dx, int dy, int status,				int time) {			currentText = this.getText();			int oldCurrentChar = currentChar;			if (Math.abs(dx) > Math.abs(dy)) {				// horizontal scroll				if (dx > 0) {					currentChar = Math.min(currentText.length() - 1,							currentChar + 1);				} else if (dx < 0) {					currentChar = Math.max(0, currentChar - 1);				}				if (oldCurrentChar != currentChar) {					this.invalidate();				}				return true;			} else {				return super.navigationMovement(dx, dy, status, time);			}		}	};

1 楼 女巫の微笑 2010-03-04  

谢谢  真是帮忙了

2 楼 doll 2010-03-07  

女巫の微笑 写道

谢谢  真是帮忙了

能帮你我很高兴 不用客气

3 楼 michael_wang 2010-10-11  

留个脚印