Android implementation three-level linkage drop-down box drop-down list spinner instances

Main implementation: Dynamically load all levels drop-down values of the adapter

In the listen to this level drop-down box, when the selected value of this level drop-down box changes, the binding value of the subordinate adapter is modified with it

XML layout:

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android"    xmlns:tools= "http// Schemas.android.com/tools "    android:layout_width=" match_parent "    android:layout_height=" Wrap_content "    android:orientation= "Horizontal"    android:padding= "8DP" >    <spinner        android:id= "@+id/spin_ Province "        android:layout_width=" 80DP "        android:layout_height=" wrap_content "/>    <spinner        Android:id= "@+id/spin_city"        android:layout_width= "112DP"        android:layout_height= "Wrap_content"/>    <spinner        android:id= "@+id/spin_county"        android:layout_width= "100DP"        android:layout_ height= "Wrap_content"/></linearlayout>

Implementation code:

Package Com.example.android.demo.spinner;import Android.os.bundle;import Android.app.activity;import Android.view.view;import Android.widget.adapterview;import Android.widget.arrayadapter;import  Android.widget.spinner;public class Mainactivity extends activity{private Spinner provincespinner = null;     Provincial (province and municipality) private Spinner cityspinner = null;    Prefecture-level private Spinner Countyspinner = null;  County level (district, county, city) arrayadapter<string> provinceadapter = null;    Provincial adapter arrayadapter<string> cityadapter = null;    Ground level adapter arrayadapter<string> countyadapter = null;        County-level Adapter static int provinceposition = 3;    Provincial option value Private string[] province = new string[] {"Beijing", "Shanghai", "Tianjin", "Guangdong"};//, "Chongqing", "Heilongjiang", "Jiangsu", "Shandong", "Zhejiang", "Hong Kong", "Macau"}; Ground level option value private string[][] City = new string[][] {{"Dongcheng", "Xicheng", "Chongwen District", "Xuanwu District", "Chaoyang District", "Haidian", "Fengtai", "Shijingshan", "Mentougou", "Fangshan", "Tongzhou District", "Shunyi District", "Daxing District", "Changping District", "Pinggu District", "Huairou", "Miyun", "Yanqing County"}, {"Changning", "Jingan", "Putuo", "Zhabei", "Hongkou"}, { "Heping", "Hedong", "Hexi District", "Nankai District", "Hebei District", "Hongqiao District", "Tanggu District", "Hangu District", "Grand Port District", "Dongli District"}, {" Guangzhou "," Shenzhen "," Shaoguan "//," Zhuhai "," Shantou "," Foshan "," Zhanjiang "," Zhaoqing "," Jiangmen "," Maoming "," Huizhou "," Meizhou ",//" Shanwei "," Heyuan "," Yangjiang "," Qingyuan "," Dongguan "," Zhongshan "," Chaozhou "    , "Jieyang", "Yunfu"};                        County option value Private string[][][] County = new string[][][] {//Beijing {"None"},{"No"},{"None"},{"None"},{"None"},{"None"},{"None"},{"None"},{"None"},{"None"}, {"None"},{"None"},{"None"},{"None"},{"None"},{"None"},{                    "None"},{"no"}, {//Shanghai {"None"},{"None"},{"None"},{"None"},{"None"} }, {//Tianjin {"No"},{"no"},{"None"},{"None"},{"None"},{"None"},{"None"},{"None"},{"None"},{ "None"}, {//Guangdong {"Haizhu District", "Liwan District", "Yuexiu District"), "Baiyun District", "Luogang District", "Tianhe District", "Huangpu District", "Huadou District", "Conghua", "Add City", "Fanyu District", "Nansha"},//guangzhou {"Baoan District", "Futian District", "Longgang District", "Luohu", "Nanshan", "Yantian District"}            ,//Shenzhen {"Wujiang District", "Zhenzhou District", "Qujiang District", "Lechang", "Nanxiong", "Shixing County", "Renhua County", "Wengyuan County", "Xinfeng County", "Ruyuan County"}//Shaoguan}        };        @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);        Setcontentview (R.layout.activity_main);    Setspinner (); }/* * Set dropdown box */private void Setspinner () {Provincespinner = (Spinner) Findviewbyid (R.        Id.spin_province);        Cityspinner = (Spinner) Findviewbyid (r.id.spin_city);        Countyspinner = (Spinner) Findviewbyid (R.id.spin_county); Bind adapter and value Provinceadapter = new Arrayadapter<string> (Mainactivity.this, Android.        R.layout.simple_spinner_item, province);        Provincespinner.setadapter (Provinceadapter);  Provincespinner.setselection (3,true); Sets the default check, where the 4th value is checked by default CityadaPter = new Arrayadapter<string> (Mainactivity.this, Android.        R.layout.simple_spinner_item, city[3]);        Cityspinner.setadapter (Cityadapter);  Cityspinner.setselection (0,true); The No. 0 countyadapter = new arrayadapter<string> (Mainactivity.this, Android) is selected by default.        R.layout.simple_spinner_item, county[3][0]);        Countyspinner.setadapter (Countyadapter);                Countyspinner.setselection (0, true);  Provincial drop-down frame monitor provincespinner.setonitemselectedlistener (new Adapterview.onitemselectedlistener () {// Indicates that the option is changed to trigger this method, the main implementation: dynamically change the binding value of the ground level adapter @Override public void onitemselected (adapterview<?> arg0 , View arg1, int position, long Arg3) {//position is the ordinal of the current provincial selected value//change the value of the ground level adapter to city[ Position] Value Cityadapter = new Arrayadapter<string> (Mainactivity.this, Androi D.r.layout.simple_spinner_item, City[position]);                Set the option for Level two drop-down list of content adapter Cityspinner.setadapter (cityadapter);    Provinceposition = position; Record the current provincial serial number, leave the following to modify the county-level adapter when used} @Override public void onnothingselected (adapterview<?> a                rg0) {}}); Ground level dropdown monitor Cityspinner.setonitemselectedlistener (new Adapterview.onitemselectedlistener () {@Overri             De public void onitemselected (adapterview<?> arg0, View arg1, int position, long arg3) {countyadapter = new arrayadapter<string> (Mainactivity.this, Android Oid.                R.layout.simple_spinner_item, county[provinceposition][position]);            Countyspinner.setadapter (Countyadapter);        } @Override public void onnothingselected (Adapterview<?> arg0) {}    }); }}

To get the selected value in the drop-down box spinner, use this method to OK.

Provincespinner.getselecteditem (). toString ();

Cityspinner.getselecteditem (). toString ();

Countyspinner.getselecteditem (). toString ();

The END

Android implementation three-level linkage drop-down box drop-down list spinner instances