Android uses spannablestring to display compound text

http://blog.csdn.net/feizhixuan46789/article/details/10334441

Http://www.th7.cn/Program/Android/201408/258951.shtml

In the actual application development process often encountered, in different parts of the text display some different font style information such as: text font, size, color, style, and hyperlinks. In general, the text in TextView is a style, and for a similar scenario, you can use the Spannablestring or Spannablestringbuilder object to implement the above settings.

Spannablestring and Spannablestringbuilder can set a paragraph of text to a span, and in Android, span represents the effect of a piece of text, such as a link form, an image, text with a background, and so on. Just the difference is that Spannablestringbuilder can modify the contents of the text.

Ax, let's get acquainted with the Spannablestring class first.

Class Structure:

The content of such text is immutable, but the tagged object can be appended and detached. For mutable text, see Spannablestringbuilder. class overview:

Construction Method:

Public constructors
Spannablestring (charsequence Source)

Common public methods:

Public Methods
Final Char	charAt (int i) Returns the character at the specified index, with the index of the first character at 0.
Boolean	Equals (Object o) Compares this instance with the specified object and indicates if they is equal. Compares this instance with the specified object, and returns True if it is equal.
Final void	GetChars (int start, int end, char[] dest, int off) Similar to the String.getchars () method: Copies characters from the specified character array. Start position, end position, off offset.
Int	Getspanend (Object what) Gets the end position of the what object in the Spannablestring object. If no match is returned-1.
Int	Getspanstart (Object what) Gets the start position of the What object in the Spannablestring object. If no match is returned-1.
Final int	Length () Returns the number of characters in this sequence.
void	Removespan (Object what) Removes the specified object from the range of text.
void	Setspan (Object what, int start, int end, int flags) Sets a span object. What

Description

void Setspan (Object what, int start, int end, int flags)

Sets a span object. The first parameter is what: represents the effect of a piece of text, which can accept the following properties:

Property name	Description
Backgroundcolorspan	Background color
Clickablespan	Text clickable, with click events
Foregroundcolorspan	Text colors (foreground color)
Maskfilterspan	Cosmetic effects, such as Blur (Blurmaskfilter) emboss (Embossmaskfilter)
Metricaffectingspan	Parent class, usually not used
Rasterizerspan	Grating effect
Strikethroughspan	Strikethrough (in dash)
Suggestionspan	Equivalent to a placeholder
Underlinespan	Underline
Absolutesizespan	Absolute size (text font)
Dynamicdrawablespan	Sets the picture, based on the text baseline or bottom alignment.
Imagespan	Image
Relativesizespan	Relative size (text font)
Replacementspan	Parent class, usually not used
Scalexspan	Scale based on X-axis
Stylespan	Font style: bold, italic, etc.
Subscriptspan	Subscript (The mathematical formula will be used)
Superscriptspan	Superscript (the mathematical formula will be used)
Textappearancespan	Text appearance (including font, size, style, and color)
Typefacespan	Text font
Urlspan	Text hyperlinks

The second and third parameters represent the position of the beginning and the next character of the ending position of the text in which the text is to be set to span, that is, start and end. The last parameter (flags) is a flag. You can also set several similar values such as the following:

Spanned.span_exclusive_inclusive: The character entered in front of span does not apply the effect of span, and the span effect is applied to the characters entered later.

Spanned.span_inclusive_exclusive: The character entered before span applies the effect of span, and the character entered later does not apply a span effect.

Spanned.span_incujsive_inclusive: The effect of span is applied to characters entered before and after span.

Android uses spannablestring to display compound text