zoukankan html css js c++ java

选择改变事件OnCheckedChange

1.效果图：选择正确的提示选对，选择错误提示选错

2.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="match_parent"
 6    android:orientation="vertical"
 7     tools:context="com.example.app5.MainActivity">
 8 
 9     <TextView
10         android:layout_width="wrap_content"
11         android:layout_height="wrap_content"
12         android:text="请选择正确的题目" />
13     <RadioGroup
14         android:id="@+id/rg"
15         android:layout_width="wrap_content"
16         android:layout_height="wrap_content">
17         <RadioButton
18             android:id="@+id/rb_1"
19             android:text="1+1=3"
20             android:layout_width="wrap_content"
21             android:layout_height="wrap_content" />
22         <RadioButton
23             android:id="@+id/rb_2"
24             android:text="1+1=2"
25             android:layout_width="wrap_content"
26             android:layout_height="wrap_content" />
27         <RadioButton
28             android:id="@+id/rb_3"
29             android:text="1+1=4"
30             android:layout_width="wrap_content"
31             android:layout_height="wrap_content" />
32         <RadioButton
33             android:id="@+id/rb_4"
34             android:text="1+1=5"
35             android:layout_width="wrap_content"
36             android:layout_height="wrap_content" />
37 
38     </RadioGroup>
39 </LinearLayout>

2.MainActivity.java

 1 package com.example.app5;
 2 
 3 import android.support.v7.app.AppCompatActivity;
 4 import android.os.Bundle;
 5 import android.widget.RadioButton;
 6 import android.widget.RadioGroup;
 7 import android.widget.Toast;
 8 
 9 public class MainActivity extends AppCompatActivity {
10     private RadioGroup rg;
11     private RadioButton rb_1,rb_2,rb_3,rb_4;
12 
13     @Override
14     protected void onCreate(Bundle savedInstanceState) {
15         super.onCreate(savedInstanceState);
16         setContentView(R.layout.activity_main);
17         rg=(RadioGroup)findViewById(R.id.rg);
18         rb_1 = (RadioButton) findViewById(R.id.rb_1);
19         rb_2 = (RadioButton) findViewById(R.id.rb_2);
20         rb_3= (RadioButton) findViewById(R.id.rb_3);
21         rb_4 = (RadioButton) findViewById(R.id.rb_4);
22 
23         rg.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
24             @Override
25             public void onCheckedChanged(RadioGroup group, int checkedId) {
26 
27                 //switch实现方式
28                 /*switch (checkedId){
29                     case R.id.rb_1:
30                         Toast.makeText(MainActivity.this,"您选错了"+rb_1.isChecked(),Toast.LENGTH_SHORT).show();
31                         break;
32                     case R.id.rb_2:
33                         Toast.makeText(MainActivity.this,"您选对了"+rb_2.isChecked(),Toast.LENGTH_SHORT).show();
34                         break;
35                     case R.id.rb_3:
36                         Toast.makeText(MainActivity.this,"您选错了"+rb_3.isChecked(),Toast.LENGTH_SHORT).show();
37                         break;
38                     case R.id.rb_4:
39                         Toast.makeText(MainActivity.this,"您选错了"+rb_4.isChecked(),Toast.LENGTH_SHORT).show();
40                         break;*/
41 
42                  //if 判断实现方式
43               /*  if(R.id.rb_2==checkedId){
44                     Toast.makeText(MainActivity.this,"正确"+rb_2.isChecked(),Toast.LENGTH_SHORT).show();
45                 } else {
46                     Toast.makeText(MainActivity.this,"错误",Toast.LENGTH_SHORT).show();
47                 }*/
48 
49                 //对象的实现方式
50                 RadioButton r = (RadioButton) findViewById(checkedId);
51                 if(r.equals(rb_2)){
52                     Toast.makeText(MainActivity.this,"正确"+rb_2.isChecked(),Toast.LENGTH_SHORT).show();
53                 }else{
54                     Toast.makeText(MainActivity.this,"错误",Toast.LENGTH_SHORT).show();
55                 }
56             }
57         });
58 
59 
60     }
61 }

2.效果图：多选按钮，选择哪个之后提示选择了XX

（1）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="match_parent"
 6    android:orientation="vertical"
 7     tools:context="com.example.app6.MainActivity">
 8 
 9     <TextView
10         android:layout_width="wrap_content"
11         android:layout_height="wrap_content"
12         android:text="您的爱好是" />
13     <CheckBox
14         android:id="@+id/cb_1"
15         android:text="sing"
16         android:layout_width="wrap_content"
17         android:layout_height="wrap_content" />
18     <CheckBox
19         android:id="@+id/cb_2"
20         android:text="game"
21         android:layout_width="wrap_content"
22         android:layout_height="wrap_content" />
23     <CheckBox
24         android:id="@+id/cb_3"
25         android:text="eat food"
26         android:layout_width="wrap_content"
27         android:layout_height="wrap_content" />
28 
29 </LinearLayout>

View Code

(2)MainActivity.java

 1 package com.example.app6;
 2 
 3 import android.support.v7.app.AppCompatActivity;
 4 import android.os.Bundle;
 5 import android.widget.CheckBox;
 6 import android.widget.CompoundButton;
 7 import android.widget.Toast;
 8 
 9 public class MainActivity extends AppCompatActivity {
10 
11     private CheckBox cb_1,cb_2,cb_3;
12     @Override
13     protected void onCreate(Bundle savedInstanceState) {
14         super.onCreate(savedInstanceState);
15         setContentView(R.layout.activity_main);
16         cb_1=(CheckBox)findViewById(R.id.cb_1);
17         cb_2=(CheckBox)findViewById(R.id.cb_2);
18         cb_3=(CheckBox)findViewById(R.id.cb_3);
19 
20         cb_1.setOnCheckedChangeListener(new myListener());
21         cb_2.setOnCheckedChangeListener(new myListener());
22         cb_3.setOnCheckedChangeListener(new myListener());
23 
24     }
25    class myListener implements CompoundButton.OnCheckedChangeListener {
26 
27        @Override
28        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
29 
30            //switch实现
31           /* switch (buttonView.getId()){
32                case R.id.cb_1:
33                    Toast.makeText(MainActivity.this,cb_1.getText().toString()+"  "+((CheckBox)buttonView).isChecked() ,Toast.LENGTH_SHORT).show();
34                    break;
35                case R.id.cb_2:
36                    Toast.makeText(MainActivity.this,cb_2.getText().toString()+"  "+((CheckBox)buttonView).isChecked() ,Toast.LENGTH_SHORT).show();
37                     break;
38                case R.id.cb_3:
39                    Toast.makeText(MainActivity.this,cb_3.getText().toString()+"  "+((CheckBox)buttonView).isChecked() ,Toast.LENGTH_SHORT).show();
40                     break;
41            }*/
42 
43            //if实现
44            if(isChecked){
45                Toast.makeText(MainActivity.this,buttonView.getText().toString()+"  "+(buttonView).isChecked() ,Toast.LENGTH_SHORT).show();
46            } else{
47                Toast.makeText(MainActivity.this,buttonView.getText().toString()+"  "+(buttonView).isChecked() ,Toast.LENGTH_SHORT).show();
48 
49            }
50        }
51    }
52 }

View Code

3.效果图

（1）activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.app7.MainActivity">


    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="您的爱好是" />
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <CheckBox
            android:id="@+id/sing"
            android:text="sing"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
        <CheckBox
            android:id="@+id/game"
            android:text="game"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
        <CheckBox
            android:id="@+id/eat"
            android:text="eat"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </LinearLayout>
    <Button
        android:id="@+id/bt"
        android:text="提交"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

(2)MainAcivity.xml

 1 package com.example.app7;
 2 
 3 import android.support.v7.app.AppCompatActivity;
 4 import android.os.Bundle;
 5 import android.view.View;
 6 import android.widget.Button;
 7 import android.widget.CheckBox;
 8 import android.widget.Toast;
 9 
10 import java.util.ArrayList;
11 import java.util.List;
12 
13 public class MainActivity extends AppCompatActivity {
14     private Button bt;
15     private CheckBox sing;
16     private  CheckBox game;
17     private  CheckBox eat;
18     private List<CheckBox> list;
19     private int count=0;
20 
21     @Override
22     protected void onCreate(Bundle savedInstanceState) {
23         super.onCreate(savedInstanceState);
24         setContentView(R.layout.activity_main);
25 
26         sing = (CheckBox) findViewById(R.id.sing);
27         game = (CheckBox) findViewById(R.id.game);
28         eat = (CheckBox) findViewById(R.id.eat);
29         bt = (Button) findViewById(R.id.bt);
30         list = new ArrayList<>();
31         list.add(sing);
32         list.add(game);
33         list.add(eat);
34 
35         bt.setOnClickListener(new View.OnClickListener() {
36             @Override
37             public void onClick(View v) {
38                 StringBuffer sb = new StringBuffer();;
39                 for (CheckBox checkbox:list){
40                     if (checkbox.isChecked()){
41                         count++;
42                         sb.append(checkbox.getText().toString()+"  ");
43                     }
44                 }
45                 if(sb==null||"".equals(sb.toString())){
46                     Toast.makeText(MainActivity.this,"至少选择一项",Toast.LENGTH_SHORT).show();
47                 }else {
48                     Toast.makeText(MainActivity.this,sb.toString()+",共"+count+"项",Toast.LENGTH_SHORT).show();
49                     count=0;
50                 }
51             }
52         });
53     }
54 }

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原文地址：https://www.cnblogs.com/sunxiaoyan/p/9007983.html