Android 选项控件

1.activity_main.xml布局

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


    <RadioGroup
        android:id="@+id/group"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <RadioButton
            android:id="@+id/android"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Android" />

        <RadioButton
            android:id="@+id/java"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="java" />

        <RadioButton
            android:id="@+id/c"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="c++" />
    </RadioGroup>

    <TextView
        android:id="@+id/show"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp" />

    <CheckBox
        android:id="@+id/box1"
        android:layout_marginTop="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="语文" />

    <CheckBox
        android:id="@+id/box2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="数学" />

    <CheckBox
        android:id="@+id/box3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="英语" />

    <TextView
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:id="@+id/show2"
        android:layout_marginTop="10dp"
        />

</LinearLayout>

2.MainActivity.java

package demo.com.danxuankuang;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    RadioGroup group;
    TextView show;
    TextView show2;
    CheckBox box1;
    CheckBox box2;
    CheckBox box3;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        group = findViewById(R.id.group);
        show = findViewById(R.id.show);


        show2 = findViewById(R.id.show2);
        box1 = findViewById(R.id.box1);
        box2 = findViewById(R.id.box2);
        box3 = findViewById(R.id.box3);
        //复选框设置监听事件
        CheckList checkList = new CheckList();
        box1.setOnCheckedChangeListener(checkList);
        box2.setOnCheckedChangeListener(checkList);
        box3.setOnCheckedChangeListener(checkList);

        //单选框设置监听事件
        group.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                switch (checkedId) {
                    case R.id.android:
                        show.setText("你选择了:Andrlid");
                        break;
                    case R.id.java:
                        show.setText("你选择了:Java");
                        break;
                    case R.id.c:
                        show.setText("你选择了:C++");
                        break;
                    default:
                        break;

                }
            }
        });


    }

    //选中的回调函数
    class CheckList implements CompoundButton.OnCheckedChangeListener {
        StringBuilder sb = new StringBuilder();
        String str;

        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            switch (buttonView.getId()) {
                case R.id.box1:
                    str = "语文";
                    chage(str,isChecked);
                    show2.setText(sb.toString());
                    break;
                case R.id.box2:
                    str = "数学";
                    chage(str,isChecked);
                    show2.setText(sb.toString());
                    break;
                case R.id.box3:
                    str = "英语";
                    chage(str,isChecked);
                    show2.setText(sb.toString());
                    break;
                default:
                    break;
            }
        }

        /**
         * 对选中按钮字符串的拼接和删除操作
         * @param str  要操作的字符
         * @param bb   判断是否选中
         */
        private void chage(String str,boolean bb){
            if(bb){
                //字符串拼接
               sb.append(str);
            }else {
                //字符串删除
                int start = str.indexOf(str);
                //如果字符串存在
                if(start!=-1){
                    int end = str.length()+start;
                    sb.delete(start,end);
                }
            }
        }
    }



}