引用：http://www.4ucode.com/Study/Topic/910199
字体样式大小都是用Paint类定义的。
public void getTextBounds(String text, int start, int end, Rect bounds)
Return in bounds (allocated by the caller) the smallest rectangle that encloses all of the characters, with an implied origin at (0,0).
Parameters
text String to measure and return its bounds
start Index of the first char in the string to measure
end 1 past the last char in the string measure
bounds Returns the unioned bounds of all the text. Must be allocated by the caller.
比如：
private final Paint pFont = new Paint();
Rect rect = new Rect();
pFont.getTextBounds(“辉”, 0, 1, rect);
Log.v(TAG, “height:”+rect.height()+””+rect.width());