Font
In the mobile programming of j2-based mobile phones, we can use the Font class to achieve better performance in the low-level user interface. How can we use the Font class?
First, due to restrictions on mobile phone devices, the Font types supported by mobile phones are very limited. Therefore, you can only use the default Font supported by mobile phones to construct Font-type objects. The following describes how to create a Font Class Object:
GetFont (int face, int style, int size );
For example:
Font font = Font. getFont (Font. FACE_SYSTEM, Font. STYLE_BOLD, Font. SIZE_MEDIUM );
No matter which parameter, you can only use the value set by the system. The specific size of these values may be different on different mobile phones. The following describes the values of the three parameters in detail:
The face parameter indicates the font appearance. The value can be:
FACE_MONOSPACE -- same width font
FACE_PROPORTIONAL -- balanced font
FACE_SYSTEM -- System font
The style parameter indicates the font style. The value can be:
STYLE_BOLD -- bold
STYLE_ITALIC -- Italic
STYLE_PLAIN -- normal
STYLE_UNDERLINED -- underline
STYLE_BOLD | STYLE_ITALIC -- bold italic
STYLE_UNDERLINED | STYLE_BOLD -- underlined and bold
STYLE_UNDERLINED | STYLE_ITALIC -- italic with underline
STYLE_UNDERLINED | STYLE_ITALIC | STYLE_BOLD -- bold italic with underlines
The size parameter indicates the font size. The value can be:
SIZE_SMALL -- small
SIZE_MEDIUM -- medium
SIZE_LARGE -- large
The preceding parameter values can be used to combine the font objects you need.
Below are some common font operations:
1. Obtain the default font of the system:
Font font = Font. getDefaultFont ();
2. In the panit method, if the Graphics parameter is named g, the method for obtaining the current font is:
Font font = g. getFont ();
3. In the panit method, if the Graphics parameter is named g, the current font is set as follows:
G. setFont (font );
Font indicates the font object you have constructed.
4. In MIDP2.0, you can set the font format of each line in List:
List. setFont (0, font );
The above Code sets the first line in the list as a font.
Use color
Color is often used for painting during the development process of the mobile phone program for enhancing the performance of the program. The following describes how to use color.
Due to the relatively simple technology, the special color class is not implemented, but the RGB concept is used to represent the color. Here we will briefly introduce the concept of RGB. colors are composed of three primary colors: Red, Green, and Blue, therefore, the combination of these three colors can be used to represent a specific color. Each value of R, G, and B is between 0 and. When expressing colors, you can use three numbers or a hexadecimal format, such as 0X00RRGGBB. The following is a common expression of colors:
Red :( 255, 0, 0) or 0x00FF0000
Green: (0,255, 0) or 0x0000FF00
Blue: (255,255,255) or 0x00FFFFFF
Other colors can also be combined through the above method.
After learning about the color expression, we will introduce how to use the color in the j2s program. The methods involved are in the Graphics class, including the following:
1. getColor ():
Obtain the current color. The returned value is a number in 0x00RRGGBB format. For example:
int color = g.getColor();
Where g is a Graphics type object.
2. setColor (int RGB ):
Set the color used. For example:
g.setColor(0x00ff0000);
3. setColor (int red, int green, int blue)
It works the same way as the preceding method, for example:
g.setColor(255,0,0);
After the color used by Graphics is set, you can draw the specified color.