Referring to the right image in FIGURE 5, the full screen display area is defined as the upper left coordinate of the display area, (screenPaintableRegion.x, screenPaintableRegion.y), and the bottom right coordinate of the screen area (screen.x+screen.width, screen.y+screen.height).
Customization of the display area will be available in future versions of the Wireless Toolkit.
Screen Pixel Ratio
The following commands enable you to compensate for the difference in aspect ratio between the actual device screen and the device image on the PC screen.
The pixel size ratio property defines the number of pixels in the device’s PC image that correspond to a single pixel on the real device in both the horizontal and vertical direction.
Note – MIDP requires that pixels be square. Therefore, you should only use pixel ratios that preserve the square, for example, x:y = 2:2 or 3:3 (that is, magnifying the image), and you should not use pixel ratios that distort the square, for example, x:y = 1:2 or 2:1.
The ratios are defined as follows:
screenPixelRatio.x = horizontal_image_pixels/ horizontal_device_pixels
screenPixelRatio.y = vertical_image_pixels/vertical_device_pixels
For most devices, use the following values:
screenPixelRatio.x = 1 screenPixelRatio.y = 1
The values of screenPixelRatio.x and screenPixelRatio.y must be whole numbers.
Screen Background Color
For a device with a grayscale screen, the background color of the screen can be set. The color is defined as a hexadecimal integer according to the standard Java color map. That is, the integer has the form RRGGBB, where RR, GG, and BB are the red, green and blue components of the color, respectively. For example, white would be 0xffffff and red would be 0xff0000.
The background color is defined with the property screenBGColor.
For example:
screenBGColor = 0x64b890
Chapter 3 Examining Device Property Files 27