安卓四级级联下拉框效果实现

Posted 2021-02-28 Mem_Ocean

突然想起来，安卓这块的随笔荒废好久了……T^T

   今天因为大创的任务的要求，需要实现四级级联的下拉框的效果，所以趁着这个机会利用spinner实现了级联下拉框的效果，以下是效果图。

   话不多说，上代码了,首先是activity_main.xml，

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="wrap_content"
 6     android:orientation="vertical"
 7     android:padding="8dp" >
 8     <Spinner
 9         android:id="@+id/spin_institue"
10         android:layout_width="match_parent"
11         android:layout_height="wrap_content" />
12 
13     <Spinner
14         android:id="@+id/spin_grade"
15         android:layout_width="100dp"
16         android:layout_height="wrap_content" />
17 
18     <Spinner
19         android:id="@+id/spin_prof"
20         android:layout_width="match_parent"
21         android:layout_height="wrap_content" />
22     <Spinner
23         android:id="@+id/spin_class"
24         android:layout_width="100dp"
25         android:layout_height="wrap_content" />
26     <Button
27         android:layout_width="match_parent"
28         android:layout_height="wrap_content"
29         android:text="上传"
30         android:id="@+id/up_btn"/>
31 </LinearLayout>

activity_main.xml

   然后是对应的MainActivity.java

  1 package com.example.tryy;
  2 
  3 import android.content.Intent;
  4 import android.support.v7.app.AppCompatActivity;
  5 import android.os.Bundle;
  6 import android.util.Log;
  7 import android.view.View;
  8 import android.widget.AdapterView;
  9 import android.widget.ArrayAdapter;
 10 import android.widget.Button;
 11 import android.widget.Spinner;
 12 import android.widget.Toast;
 13 
 14 import java.util.HashMap;
 15 
 16 public class MainActivity extends AppCompatActivity {
 17     private Spinner insspinner=null;
 18     private Spinner graspinner=null;
 19     private Spinner prospinner=null;
 20     private Spinner claspinner=null;
 21     private Button up_btn=null;
 22     ArrayAdapter<String> insAdapter = null;
 23     ArrayAdapter<String> graAdapter = null;
 24     ArrayAdapter<String> proAdapter = null;
 25     ArrayAdapter<String> claAdapter=null;
 26     static int insPosition = 0;
 27     static int graPosition=0;
 28     static int proPosition=0;
 29     static int claPosition=0;
 30     private String upload_str;
 31     HashMap<String, String> hm = new HashMap<String, String>();
 32 
 33 
 34 
 35     private String[] ins = new String[] {"计算机科学与技术学院"};
 36     private String[][] gra=new String[][]{
 37             {"16","17","18","19"}
 38     };
 39     private String[][][] prof=new String[][][]{
 40             {{"计算机科学与技术","电子信息科学与技术","信息安全","网络工程"},
 41             {"计算机科学与技术","电子信息科学与技术","信息安全"},
 42             {"计算机科学与技术","电子信息科学与技术","信息安全","数据科学与大数据技术专业"},
 43             {"计算机类"}}
 44     };
 45     private String[][][][] cla=new String[][][][]{
 46             {
 47         {{"01","02","03","04","05","06","07"}, {"01","02","03","04"},{"01","02","03","04"},{"01"}},
 48             {{"01","02","03","04","05","06"}, {"01","02","03","04"},{"01","02","03","04"}},
 49             {{"01","02","03","04"}, {"01","02","03","04"},{"01","02","03","04"},{"01","02"}},
 50             {{"01","02","03","04","05","06","07","08","09","10","11","12","13"}}
 51             }
 52     };
 53 
 54 
 55     @Override
 56     protected void onCreate(Bundle savedInstanceState) {
 57         super.onCreate(savedInstanceState);
 58         setContentView(R.layout.activity_main);
 59         hm.put("计算机类", "0801");
 60         hm.put("计算机科学与技术", "0810");
 61         hm.put("电子信息科学与技术", "0820");
 62         hm.put("网络工程", "0830");
 63         hm.put("信息安全", "0840");
 64         hm.put("数据科学与大数据技术专业", "0850");
 65         up_btn=findViewById(R.id.up_btn);
 66         up_btn.setOnClickListener(new Buttonlistener());
 67         setSpinner();
 68     }
 69     private class Buttonlistener implements View.OnClickListener {
 70         public void onClick(View v) {
 71             switch (v.getId()) {
 72                 case R.id.up_btn:
 73                     //***************************************************************************
 74                     //这里写上传的代码,上传图片与识别码，识别码就是upload_str,它的构成为GGPPPPCC,GG年级,PPPP专业号,CC班级号，比如 17081004 代表17级计算机科学与技术4班
 75 
 76                     Toast.makeText(MainActivity.this,upload_str,Toast.LENGTH_SHORT ).show();
 77                     break;
 78                 default:
 79                     break;
 80             }
 81         }
 82     }
 83     private void setSpinner(){
 84         insspinner=findViewById(R.id.spin_institue);
 85         graspinner=findViewById(R.id.spin_grade);
 86         prospinner=findViewById(R.id.spin_prof);
 87         claspinner=findViewById(R.id.spin_class);
 88 
 89         insAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item, ins);
 90         insspinner.setAdapter(insAdapter);
 91         insspinner.setSelection(0,true);
 92 
 93         graAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item, gra[0]);
 94         graspinner.setAdapter(graAdapter);
 95         graspinner.setSelection(0,true);
 96 
 97         proAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item, prof[0][0]);
 98         prospinner.setAdapter(proAdapter);
 99         prospinner.setSelection(0,true);
100 
101         claAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item, cla[0][0][0]);
102         claspinner.setAdapter(claAdapter);
103         claspinner.setSelection(0,true);
104 
105         insspinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener()
106         {
107 
108             // 表示选项被改变的时候触发此方法，主要实现办法：动态改变地级适配器的绑定值
109             @Override
110             public void onItemSelected(AdapterView<?> arg0, View arg1, int position, long arg3)
111             {
112                 //position为当前省级选中的值的序号
113 
114                 //将地级适配器的值改变为city[position]中的值
115                 graAdapter = new ArrayAdapter<String>(
116                         MainActivity.this, android.R.layout.simple_spinner_item, gra[position]);
117                 // 设置二级下拉列表的选项内容适配器
118                 graspinner.setAdapter(graAdapter);
119                 insPosition = position;    //记录当前省级序号，留给下面修改县级适配器时用
120             }
121 
122             @Override
123             public void onNothingSelected(AdapterView<?> arg0)
124             {
125 
126             }});
127 
128 
129         //地级下拉监听
130         graspinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener()
131         {
132 
133             @Override
134             public void onItemSelected(AdapterView<?> arg0, View arg1,
135                                        int position, long arg3)
136             {
137                 proAdapter = new ArrayAdapter<String>(MainActivity.this,
138                         android.R.layout.simple_spinner_item,prof[insPosition][position]);
139                 prospinner.setAdapter(proAdapter);
140                 graPosition=position;
141             }
142 
143             @Override
144             public void onNothingSelected(AdapterView<?> arg0)
145             {
146 
147             }});
148 
149         prospinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener()
150         {
151 
152             @Override
153             public void onItemSelected(AdapterView<?> arg0, View arg1,
154                                        int position, long arg3)
155             {
156                 claAdapter = new ArrayAdapter<String>(MainActivity.this,
157                         android.R.layout.simple_spinner_item, cla[insPosition][graPosition][position]);
158                 claspinner.setAdapter(claAdapter);
159                 proPosition=position;
160 
161             }
162 
163             @Override
164             public void onNothingSelected(AdapterView<?> arg0)
165             {
166 
167             }});
168 
169         claspinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener()
170         {
171 
172             @Override
173             public void onItemSelected(AdapterView<?> arg0, View arg1,
174                                        int position, long arg3)
175             {
176                 claPosition=position;
177                 String str=ins[insPosition]+gra[insPosition][graPosition]+prof[insPosition][graPosition][proPosition]+cla[insPosition][graPosition][proPosition][claPosition];
178                 upload_str=gra[insPosition][graPosition]+hm.get(prof[insPosition][graPosition][proPosition])+cla[insPosition][graPosition][proPosition][claPosition];
179                 Toast.makeText(MainActivity.this,str,Toast.LENGTH_SHORT ).show();
180             }
181 
182             @Override
183             public void onNothingSelected(AdapterView<?> arg0)
184             {
185 
186             }});
187     }
188 
189 }

MainActivity.java