SWT绘图与图像处理-优快云博客

Control, Devices, Images 1. 创建一个或者维持一个 GC 2. drawing 3 . 销毁 GC GC gc = new GC(display); gc.drawRectangle(...); gc.drawText(...); gc.drawImage(...); gc.dispose(); swt 使用两维坐标系, 以(0,0)为原点, 从左到右，从上到下递增 PaintEvent 包含了一个有效的GC instance, 而且不能销毁它画布画图形的时候，相对于画布的左上角图标 fillRectangle: 是一个固态控件，没有边框 drawRectangle: 有边框 Drawing Text: 你可以显示一个text在一个单行，也可以自动换行改变font, size, color, style, orientation drawString() drawText() : 处理 newLine and tabs void drawText(String text, int x, int y, int flags) : Draws the specified string with its origin at the point specified by (x, y), processing newlines and expanding tabs. Uses the rules specified by flags (see Table 10-2 for more information). Table 10-2: drawText() Flags Constant Description SWT.DRAW_DELIMITER Processes newlines by drawing subsequent characters on the next line. (是否显示newLine) SWT.DRAW_TAB Processes tabs by displaying a gap between surrounding characters. (是否显示Tab) SWT.DRAW_MNEMONIC Draws an underline beneath the mnemonic character—the character preceded by an ampersand (&). Use this when drawing menus. (是否显示下划线) SWT.DRAW_TRANSPARENT Uses a transparent background when drawing the string (是否使文本透明) 如果你没有指定font, 就会使用Dispaly.getSystemFont() 你可以调用GC.setFont() ,但是要记得销毁掉 Font Font font = new Font(shell.getDisplay(), "Helvetica", 18, SWT.NORMAL); font.dispose(); // fontData 代表的只是Font 的数据，不要销毁它 public FontData(String name, int height, int style) // 用 gc.getStringExtend() 得到String 的宽度 int strWidht = gc.getStringExtend("abc"); int strHigh = gc.getFontMetrics().getHeight(); // 绘制背景色 gc.setForeground(display.getSystemColor(SWT.COLOR_BLUE)); gc.drawText("I'm in blue!"); // drawing vertical Text //setup 1. draw the text to an offscreen image FontMetrics fm = gc.getFontMetrics(); Point pt = gc.textExtent(string); Image stringImage = new Image(display, pt.x, pt.y); / / setp 2 Image(支持GIF, PNG, JPEG, TIFF,ICO,BMP,RLE) 1. 从一个file 中创建一个Image Image image= new Image(displau, "c:\\temp\\swt.png"); Image image = new Image(display, MyClass.getResourceAsStream("/temp/swt.png")); 2. 创建一个空的Image Image image1 = new Image(display, 300, 200); Image image2 = new Image(display, myRect); 3. 从 ImageData 中创建 Image Device 1. 你可以了解当前屏幕的一些属性