sorting string arraylist in android [duplicate]

问题

I have a string arraylist called names. How do I sort the arraylist in alphabetical order?

回答1:

ArrayList<String> names = new ArrayList<String>();
names =fillNames() // whatever method you need to fill here;
Collections.sort(names);

http://download.oracle.com/javase/6/docs/api/java/util/Collections.html#sort%28java.util.List%29

Sorts the specified list into ascending order, according to the natural ordering of its elements. All elements in the list must implement the Comparable interface. Furthermore, all elements in the list must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the list).

String implements Comparable:

java.lang Class String

java.lang.Object extended by java.lang.String

All Implemented Interfaces: Serializable, CharSequence, Comparable

http://download.oracle.com/javase/6/docs/api/java/lang/String.html

回答2:

Another solution but Collections.sort() is best. I just want to show alternative

    ArrayList<String> strings = new ArrayList<String>();
    strings.add("a");
    strings.add("ab");
    strings.add("aa");

    String[] stringsArray = new String[strings.size()];
    strings.toArray(stringsArray);
    Arrays.sort(stringsArray);

    List<String> sorted = Arrays.asList(stringsArray);

    System.out.println(sorted);

回答3:

import java.util.Collections;

then use Collections.sort();

来源：https://stackoverflow.com/questions/5814791/sorting-string-arraylist-in-android

标签

java

sorting

arraylist