Implementation of a three-level linkage address list for Android province, city, and district

In the previous article, we introduced how to obtain data from provinces, cities, and cities. Now we will introduce an example of how to use the spinner control to implement Level 3 linkage between provinces, cities, and cities.

The following code is implemented during project development.

First, we will show the three slaves in the layout file.

<Linearlayout Android: layout_height = "40dip"
Android: layout_width = "fill_parent"
Android: Id = "@ + ID/linearlayoutarea" Android: Orientation = "horizontal">
<Spinner Android: Id = "@ + ID/spprovince" Android: layout_width = "100dip"
Android: layout_height = "wrap_content">
</Spinner>
<Spinner Android: Id = "@ + ID/spcity" Android: layout_width = "100dip"
Android: layout_height = "wrap_content">
</Spinner>
<Spinner Android: Id = "@ + ID/sparea" Android: layout_width = "100dip"
Android: layout_height = "wrap_content">
</Spinner>
</Linearlayout>

The code for assigning values to these spinner controls to bind events:

// Read the data of the province, city, and district from the database
// Initialize the province drop-down list
Private void initialprovince (){
Try {
Map <integer, list> DATA = addressutil. getprovince (File );
Provincelist = data. Get (1 );
Provincedata = data. Get (0 );
Arrayadapter provinceadapter = new arrayadapter (mcontext,
Android. R. layout. simple_spinner_item, provincelist );
Provinceadapter
. Setdropdownviewresource (Android. R. layout. simple_spinner_dropdown_item); // Style
Spprovince. setadapter (provinceadapter );
Spprovince. setonitemselectedlistener (itemselectedlistener );
} Catch (exception e ){
Log. D ("winestock", "initialprovince:" + E. getmessage ());
}
}

String selectedprovince = ""; // province selected in the drop-down list
// Save the drop-down box event
Private onitemselectedlistener itemselectedlistener = new onitemselectedlistener (){
@ Override
Public void onitemselected (adapterview <?> Parent, view,
Int position, long ID ){
Try {
Spinner spprovince = (spinner) parent;
Selectedprovince = (string) spprovince
. Getitematposition (position );
Arrayadapter cityadapter = NULL;
Map <string, integer> DATA = (MAP) provincedata. Get (position); // obtain the corresponding province id based on the selected province ID.
// Then get the city
Int pid = data. Get (selectedprovince); // obtain the province ID
Map <integer, list> citymap = addressutil
. Getcitybypid (PID, file );
Citylist = citymap. Get (1 );
Citydata = citymap. Get (0 );
Cityadapter = new arrayadapter (mcontext,
Android. R. layout. simple_spinner_item, citylist );
Cityadapter
. Setdropdownviewresource (Android. R. layout. simple_spinner_dropdown_item );
Spcity. setadapter (cityadapter );
Spcity. setonitemselectedlistener (cityselectedlistener );
} Catch (exception e ){
Log. D ("winestock", "select province error:" + E. getmessage ());
}
}

@ Override
Public void onnothingselected (adapterview <?> Parent ){
// Todo auto-generated method stub
}
};

String selectedcity = ""; // The selected city from the drop-down list
// City drop-down box event
Private onitemselectedlistener cityselectedlistener = new onitemselectedlistener (){
@ Override
Public void onitemselected (adapterview <?> Parent, view,
Int position, long ID ){
Try {
Spinner spcity = (spinner) parent;
Selectedcity = (string) spcity. getitematposition (position );
Arrayadapter areaadapter = NULL;
Map <string, integer> DATA = (MAP) citydata. Get (position); // obtain the corresponding province id based on the selected province ID.
// Then get the city
Int pid = data. Get (selectedcity); // obtain the city id
List <string> listarea = addressutil. getareabypid (PID, file );
Areaadapter = new arrayadapter (mcontext,
Android. R. layout. simple_spinner_item, listarea );
Areaadapter
. Setdropdownviewresource (Android. R. layout. simple_spinner_dropdown_item );
Sparea. setadapter (areaadapter );
Sparea. setonitemselectedlistener (areaselectedlistener );
} Catch (exception e ){
Log. D ("winestock", "select city error:" + E. getmessage ());
}

}

@ Override
Public void onnothingselected (adapterview <?> Parent ){
// Todo auto-generated method stub
}
};

String selectedarea = ""; // area selected in the drop-down box
// Area drop-down box event
Private onitemselectedlistener areaselectedlistener = new onitemselectedlistener (){
@ Override
Public void onitemselected (adapterview <?> Parent, view,
Int position, long ID ){
Try {
Spinner sparea = (spinner) parent;
Selectedarea = (string) sparea. getitematposition (position );
If (selectedprovince! = "" & Selectedcity! = ""
& Selectedarea! = ""){
String stradd = selectedprovince + selectedcity
+ Selectedarea;
Etaddress. settext (stradd );
}
} Catch (exception e ){
Log. D ("winestock", "select area error:" + E. getmessage ());
}
}

@ Override
Public void onnothingselected (adapterview <?> Parent ){
// Todo auto-generated method stub
}
};