Android Data Adapter-expandablelistview

Previously written about the usage of the ListView in Android, which can be implemented using Arrayadapter,simpleadapter,baseadapter, this time the main use of Expandablelistview shows a two-layer effect, Expandablelistview is an Android can implement the dropdown list of a control similar to the QQ kind of my friend is a row of their friends, is the two-layer effect, the implementation of the words using Simpleexpandablelistadapter can be.

Layout File

Let's look at the effect:

The XML code in main:

  <button        android:onclick= "test"        android:layout_width= "fill_parent"        android:layout_height= "Wrap_ Content "        android:text=" flyelephant "/>    <expandablelistview        android:id=" @id/android:list "        Android:layout_width= "Fill_parent"        android:layout_height= "fill_parent"        android:drawselectorontop= " False "/>

define the Province.xml of a province:

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "    android:layout_width=" match_parent "    android:layout_height=" match_parent "    android:o rientation= "vertical" >    <textview        android:id= "@+id/list_provincetext"        android:layout_width= " Fill_parent "        android:layout_height=" fill_parent "        android:paddingbottom=" 8px "        android:paddingleft=" 30px "        android:paddingright=" 5px "        android:paddingtop=" 8px "        android:textsize=" 20SP "/></ Linearlayout>

Defines the child.xml of a region:

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "    android:layout_width=" match_parent "    android:layout_height=" match_parent "    android:o rientation= "vertical" >           <textview        android:id= "@+id/child_text" android:layout_width= "Fill_        Parent "        android:layout_height=" fill_parent "        android:paddingbottom=" 8px "        android:paddingleft=" 30px "        android:paddingright= "5px"        android:paddingtop= "8px"        android:textsize= "20sp"/>    </ Linearlayout>

Demo Implementation

The main implementation of code, the code has been commented, it is not necessary to elaborate, if in doubt can comment on the district discussion:

       Create a level entry list<map<string, string>> provinces = new arraylist<map<string, string>> ()        ;        Create two provincial level entries map<string, string> firstprovince= new hashmap<string, string> ();        Firstprovince.put ("Province", "Henan");        Map<string, string> secondprovince= new hashmap<string, string> ();        Secondprovince.put ("Province", "Beijing");        Provinces.add (firstprovince);        Provinces.add (secondprovince); Create a level two entry under entry list<map<string, string>> childlist1= new arraylist<map<string, string>>        ();        Also in the first level entry directory to create two corresponding level two entries directory map<string, string> child1= new hashmap<string, string> ();        Child1.put ("Child", "Zhengzhou");        map<string, string> child2 = new hashmap<string, string> ();        Child2.put ("Child", "Kaifeng");        Childlist1.add (child1);        Childlist1.add (CHILD2); Ibid. list<map<string, string>> ChildList2 = new arraylist<map<string, string>> ();        map<string, string> child3 = new hashmap<string, string> ();        Child3.put ("Child", "Haidian");        map<string, string> child4 = new hashmap<string, string> ();        Child4.put ("Child", "changping");        Childlist2.add (CHILD3);        Childlist2.add (CHILD4); Place level two entries in a collection for display with list<list<map<string, string>>> childs = new Arraylist<list<map<s        Tring, string>>> ();        Childs.add (CHILDLIST1);        Childs.add (CHILDLIST2);         /** * Use Simpleexpandablelistadapter to display Expandablelistview * Parameter 1. Contextual Object Context * Parameter 2. First Level Entry directory collection         * Parameter 3. The layout file corresponding to the first level entry * parameter 4.fromto, which is the key in the map, specifies the object to display * parameter 5. Corresponding to parameter 4, specify the ID to display in groups * parameter 6. Two-level entry directory Collection * Parameter 7. The layout file corresponding to the two level entry * parameter 8.fromto, which is the key in the map, specifies the object to display * parameter 9. Corresponding to parameter 8, specify the ID to display in the childs */S Impleexpandablelistadapter adapter = new SIMPLEEXPANDABLELISTADAPTEr (this, provinces, R.layout.list_group, new string[] {"Province"}, new int[] {r.id.list        _grouptext}, Childs, R.layout.child, new string[] {"Child"}, new int[] {r.id.child_text}); Setlistadapter (adapter);

forget to say, mainactivity need to inherit expandablelistactivity, let's look at the final effect:

Android Data Adapter-expandablelistview