Spanned（可附加標記的字元序列）

**
 * This is the interface for text that has markup objects attached to
 * ranges of it.  Not all text classes have mutable markup or text;
 * see {@link Spannable} for mutable markup and {@link Editable} for
 * mutable text.
 */
public interface Spanned 
extends CharSequence

Spannable （可加或去除標記的字元序列）

/**
*  This is the interface for text to which markup objects can be attached and detached. 
* Not all Spannable classes have mutable text;
 * see {@link Editable} for that.
 */
public interface Spannable
extends Spanned

Editable （內容和標記都可變的字元序列）

/**
 * This is the interface for text whose content and markup can be changed 
 */
public interface Editable
extends CharSequence, GetChars, Spannable, Appendable
 

Appendable（字元文字可改變的介面）

/**
 * An object to which <tt>char</tt> sequences and values can be appended.
 *／
public interface Appendable 

SpannableString （內容不可變，標記可附加或去掉）

/**
 * This is the class for text whose content is immutable but to which
 * markup objects can be attached and detached.
 * For mutable text, see {@link SpannableStringBuilder}.
 */
public class SpannableString
extends SpannableStringInternal
implements CharSequence, GetChars, Spannable
 

SpannableString只有以下3個方法

public void setSpan(Object what, int start, int end, int flags) {
        super.setSpan(what, start, end, flags);
    }

    public void removeSpan(Object what) {
        super.removeSpan(what);
    }

    public final CharSequence subSequence(int start, int end) {
        return new SpannableString(this, start, end);
    }

SpannableStringBuilder（內容和標記都可變）

/**
 * This is the class for text whose content and markup can both be changed.
 */
public class SpannableStringBuilder implements CharSequence, GetChars, Spannable, Editable,
        Appendable, GraphicsOperations

SpannableStringBuilder有append，insert, setSpan , removeSpan方法