省市级三级联动

前言：

在我们输入信息是经常会让我们输入户籍所在地，此时省市级三级联动就很有必要了

正文：

首先在xml文件中添加如下代码

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"


    tools:context="com.example.aaaaa.sp.MainActivity">

    <TextView
        android:id="@+id/textview1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="请选择您所在的城市"
        android:textSize="20sp" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="30dp"

        >

        <Spinner

            android:id="@+id/provicespinner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1">

        </Spinner>

        <Spinner
            android:id="@+id/cityspinner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_toRightOf="@id/provicespinner"
            android:layout_weight="1">

        </Spinner>

        <Spinner
            android:id="@+id/countyspinner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_toRightOf="@id/cityspinner"
            android:layout_weight="1">

        </Spinner>
    </LinearLayout>

    <TextView
        android:id="@+id/textview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_centerVertical="true"
        android:gravity="center_horizontal"
        android:text="显示城市"
        android:textSize="20sp" />
</RelativeLayout>

Java代码如：

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private Spinner provicespinner;
    private Spinner cityspinner;
    private Spinner countyspinner;
    private ArrayAdapter<String> priviceAdapter;
    private ArrayAdapter cityAdapter;
    private ArrayAdapter contyAdapter;
    private int privicePosition;
    private int cityPosition;
    private int countyPosition;
    private String[] provice = {"山西", "江苏", "安徽"};
    private String[][] city = {{"太原", "大同", "阳泉"}, {"徐州", "南京", "苏州"}, {"宿州", "合肥", "淮北"}};
    private String[][][] county = {{{"小店区", "迎泽区", "尖草坪区"}, {"阳高县", "天镇县", "浑源县"}, {"城区",
            "郊区", "矿区"}}, {{"沛县", "丰县", "临空新城"}, {"玄武", "鼓楼", "下关"}, {"虎丘区", "吴中区",
            "吴江区"}}, {{"砀山", "萧县", "涌泉区"}, {"肥东县", "肥西县", "长丰县"}, {"杜集区", "相山区", "烈山区"}}};
    private TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textView = (TextView) findViewById(R.id.textview);
        provicespinner = (Spinner) findViewById(R.id.provicespinner);
        cityspinner = (Spinner) findViewById(R.id.cityspinner);
        countyspinner = (Spinner) findViewById(R.id.countyspinner);
        //显示省
        priviceAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1, provice);
        provicespinner.setAdapter(priviceAdapter);
        //设置省级的监听器--目的是在你选择省后直接显示对应的市，最主要的是应用position
        provicespinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                cityAdapter = new ArrayAdapter(MainActivity.this, android.R.layout.simple_list_item_1, city[position]);
                cityspinner.setAdapter(cityAdapter);
                privicePosition = position;

            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
        //给市spinner设置监听器
        cityspinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                contyAdapter = new ArrayAdapter(MainActivity.this, android.R.layout.simple_list_item_1, county[privicePosition][position]);
                countyspinner.setAdapter(contyAdapter);
                //为能把此时的position传出去
                cityPosition = position;


            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
        //为县设置适配器目的是为了显示你算选的省市县
        countyspinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                //在下面所选内容显示
                textView.setText("选择的城市为" + " " + provice[privicePosition] + " " + city[privicePosition][cityPosition] + " " + county[privicePosition][cityPosition][position]);
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
    }
}

这样实现其实就是练练手，在实际的操作中可以说用到的东西复杂的多，上面注释解释的很详细就不一步步的解释，重要的就是运用spinner的监听器里面的参数position，从而提取出上面定义的几个数组中数据