Android 复选框 以及回显

activity_main.xml

1<?xml version="1.0" encoding="utf-8"?>
2<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3    xmlns:app="http://schemas.android.com/apk/res-auto"
4    xmlns:tools="http://schemas.android.com/tools"
5    android:layout_width="match_parent"
6    android:layout_height="match_parent"
7    android:orientation="vertical"
8    tools:context=".MainActivity">
9
10
11    <TextView
12        android:id="@+id/textView"
13        android:layout_width="wrap_content"
14        android:layout_height="wrap_content"
15
16        android:text="请选择你喜欢的城市" />
17
18    <EditText
19        android:id="@+id/editText"
20        android:layout_width="wrap_content"
21        android:layout_height="wrap_content"
22
23        android:ems="10"
24        android:inputType="textPersonName"
25        android:text="你喜欢的城市有:" />
26
27
28    <CheckBox
29        android:id="@+id/checkBox"
30        android:layout_width="match_parent"
31        android:layout_height="wrap_content"
32        android:text="北京" />
33
34    <CheckBox
35        android:id="@+id/checkBox2"
36        android:layout_width="match_parent"
37        android:layout_height="wrap_content"
38        android:text="上海" />
39
40    <CheckBox
41        android:id="@+id/checkBox3"
42        android:layout_width="match_parent"
43        android:layout_height="wrap_content"
44        android:text="杭州" />
45
46    <CheckBox
47        android:id="@+id/checkBox4"
48        android:layout_width="match_parent"
49        android:layout_height="wrap_content"
50        android:text="三亚" />
51
52    <TextView
53        android:id="@+id/textView2"
54        android:layout_width="match_parent"
55        android:layout_height="wrap_content"
56        android:text="TextView" />
57
58    <Button
59        android:id="@+id/button"
60        android:layout_width="match_parent"
61        android:layout_height="wrap_content"
62        android:text="提交" />
63
64</LinearLayout>

MainActivity.java

1package com.example.myapplication;
2
3import androidx.appcompat.app.AlertDialog;
4import androidx.appcompat.app.AppCompatActivity;
5
6import android.content.DialogInterface;
7import android.content.SharedPreferences;
8import android.os.Bundle;
9import android.view.View;
10import android.widget.Button;
11import android.widget.CheckBox;
12import android.widget.CompoundButton;
13import android.widget.EditText;
14import android.widget.TextView;
15import android.widget.Toast;
16
17public class MainActivity extends AppCompatActivity {
18   
19   
20    private CheckBox a,b,c,d;
21    private TextView t1,t2;
22    private EditText et;
23    private Button b1;
24
25    @Override
26    protected void onCreate(Bundle savedInstanceState) {
27   
28   
29        super.onCreate(savedInstanceState);
30        setContentView(R.layout.activity_main);
31     
32
33        a=(CheckBox) findViewById(R.id.checkBox);
34        b=(CheckBox) findViewById(R.id.checkBox2);
35        c=(CheckBox) findViewById(R.id.checkBox3);
36        d=(CheckBox) findViewById(R.id.checkBox4);
37         t1=findViewById(R.id.textView);
38         t2=findViewById(R.id.textView2);
39         et=findViewById(R.id.editText);
40         b1=findViewById(R.id.button);
41         
42
43
44        CompoundButton.OnCheckedChangeListener lister=new CompoundButton.OnCheckedChangeListener() {
45   
46   
47           @Override
48           public void onCheckedChanged(CompoundButton ckb, boolean isChecked) {
49   
50   
51               if (isChecked){
52   
53   
54                   //Toast.makeText(MainActivity.this,t2+ckb.getText().toString(),Toast.LENGTH_LONG).show();
55                  et.setText("你选择了:"+ckb.getText());
56               }
57           }
58       };
59        a.setOnCheckedChangeListener(lister);
60        b.setOnCheckedChangeListener(lister);
61        c.setOnCheckedChangeListener(lister);
62        d.setOnCheckedChangeListener(lister);
63        b1.setOnClickListener(new View.OnClickListener() {
64   
65   
66            @Override
67            public void onClick(View v) {
68   
69   
70
71     //字符串的拼接实现复选框回显     如果  有更好的更简便  不用写那么多if判断语句可以  给小白我说下哦  多谢
72                StringBuffer result=new StringBuffer();
73                if(a.isChecked()){
74   
75   
76                    result.append(a.getText()+",");
77                }
78                if(b.isChecked()){
79   
80   
81                    result.append(b.getText()+",");
82                }
83                if(c.isChecked()){
84   
85   
86                    result.append(c.getText()+",");
87                }
88                if(d.isChecked()){
89   
90   
91                    result.append(d.getText()+",");
92                }
93                t2.setText(result.toString());
94            }
95        });
96       
97
98
99
100    }
101}