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  • Spinner 从数据库中读取数据并实现2级互动

    这里主要实现了。省份和城市的二级关联。选择省份。二级对应的就是省份所有的城市

    下面看代码;
            1.activity
            @Override
            protected void onCreate(Bundle savedInstanceState) {
                    // TODO Auto-generated method stub
                    super.onCreate(savedInstanceState);
                    setContentView(R.layout.test_layout);
                    this.mContext = this;
                    Map<Integer,List> data = ProvinceDB.getProvince();//得到数据库数据
                    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); // 样式
                   
                    spProvince.setAdapter(provinceAdapter);
                    spProvince.setOnItemSelectedListener(itemSelectedListener);
                   
            }
           
            // 选择省份 联动 对应城市
            private OnItemSelectedListener itemSelectedListener = new OnItemSelectedListener() {
                    @Override
                    public void onItemSelected(AdapterView<?> parent, View view,
                                    int position, long id) {
                            Spinner spProvince = (Spinner) parent;
                            String selProvince = (String) spProvince.getItemAtPosition(position);
                            ArrayAdapter cityAdapter = null;
                            Map<String,Integer> data = (Map)provinceData.get(position);//根据所选择的得到对应的省份id 然后得到城市
                            int pid = data.get(selProvince);//得到省份的id
                            List cityList = ProvinceDB.getCityByPid(pid);
                            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);

                    }

                    @Override
                    public void onNothingSelected(AdapterView<?> parent) {
                            // TODO Auto-generated method stub
                    }
            };
           
            String selectedCity = null;
            private OnItemSelectedListener citySelectedListener = new OnItemSelectedListener() {
                    @Override
                    public void onItemSelected(AdapterView<?> parent, View view,
                                    int position, long id) {
                            Spinner spCity = (Spinner) parent;
                            selectedCity = (String) spCity.getItemAtPosition(position);
                    }

                    @Override
                    public void onNothingSelected(AdapterView<?> parent) {
                            // TODO Auto-generated method stub
                    }
            };
           
            2.DB类查询数据
           
            public class ProvinceDB {
            public static Map<Integer,List> getProvince(){
                    String sql = "select N_PROVID ,S_PROVNAME from dict_province ";
                    SQLiteDatabase db = null;
                    Cursor c = null;
                     Map<Integer,List> provinceData = new HashMap<Integer,List>();
                    List provinceList = null;
                    try{
                            db = DatabaseHelper.getDatabase();
                            c = db.rawQuery(sql, null);
                            List provinceList1 = new ArrayList();
                            List provinceList2 = new ArrayList();
                            while(c.moveToNext()){
                                    Map provinceMap = new HashMap();
                                    provinceMap.put(c.getString(1), c.getInt(0));
                                    provinceList1.add(provinceMap);
                                    provinceList2.add(c.getString(1));
                            }
                            provinceData.put(0, provinceList1);
                            provinceData.put(1, provinceList2);
                    }catch(Exception e){
                            e.printStackTrace();
                    }finally{
                            if(c!=null){
                                    c.close();
                            }
                            if(db!=null){
                                    db.close();
                            }
                    }
                    return provinceData;
            }
           
            public static List<String> getCityByPid(int id){
                    String sql = "select S_CITYNAME  from dict_city where N_PROVID= "+id;
                    SQLiteDatabase db = null;
                    Cursor c = null;
                    List<String> cityList = null;
                    try{
                            db = DatabaseHelper.getDatabase();
                            c = db.rawQuery(sql, null);
                            cityList = new ArrayList<String>();
                            while(c.moveToNext()){
                                    cityList.add(c.getString(0));
                            }
                    }catch(Exception ex){
                            ex.printStackTrace();
                    }finally{
                            if(c!=null){
                                    c.close();
                            }
                            if(db!=null){
                                    db.close();
                            }
                    }
                    return cityList;
                   
            }
    }


    3.test_layout.xml
    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="fill_parent" android:layout_height="fill_parent"
            android:orientation="vertical">

            <LinearLayout android:layout_width="fill_parent"
                    android:layout_height="wrap_content">
                    <Spinner android:id="@+id/sp_bslProvice" android:layout_width="wrap_content"
                            android:layout_height="wrap_content" android:layout_weight="1" />
                    <Spinner android:id="@+id/sp_bslCity" android:layout_width="wrap_content"
                            android:layout_height="wrap_content" android:layout_weight="1" />
            </LinearLayout>
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  • 原文地址:https://www.cnblogs.com/kevinGao/p/2426888.html
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