首先radiogroup的佈局，重要的是設定radiogroup的三個屬性

android:background="@drawable/selector_speed_borrow_select_day"
                                    android:button="@null"
                                    android:textColor="@color/selector_select_day"

radiogroup的佈局

     <RadioGroup
                                android:id="@+
 
id/radiogroup_select_day"
                                android:layout_width="match_parent"
                                android:layout_height="80px"
                                android:layout_gravity="center_vertical"
                                android:gravity="center_vertical|right"
                                android:orientation="horizontal"
 
>

                                <RadioButton
                                    android:id="@+id/radiobtn_fifteen"
                                    android:layout_width="170px"
                                    android:layout_height="70px"
                                    android:layout_marginRight="40px"
 

                                    android:background="@drawable/selector_speed_borrow_select_day"
                                    android:button="@null"
                                    android:gravity="center"
                                    android:text="15天"
                                    android:textColor="@color/selector_select_day" />

                                <RadioButton
                                    android:id="@+id/radiobtn_thirty"
                                    android:layout_width="170px"
                                    android:layout_height="70px"
                                    android:background="@drawable/selector_speed_borrow_select_day"
                                    android:button="@null"
                                    android:gravity="center"
                                    android:text="30天"

                                    android:textColor="@color/selector_select_day" />
                            </RadioGroup>

點選背景改變的selector檔案
在res/drawable中selector_speed_borrow_select_day.xml，如果背景是圖片的話直接可以用圖片，如果背景是shape檔案

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- 預設時的背景 -->
    <item android:drawable="@drawable/shape_gradient_white_stroke_blue" android:state_checked="false"/>
    <!-- 選擇時的背景 -->
    <item android:drawable="@drawable/shape_gradient_blue" android:state_checked="true"/>
</selector>

背景為shape檔案
預設時的背景檔案shape_gradient_white_stroke_blue.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle"
    android:color="@color/white"
    >

    <stroke
        android:dashGap="0.0dip"
        android:dashWidth="0.0dip"
        android:width="1px"
         android:color="@color/text_blue"
      />
    <solid android:color="@color/white" />
    <corners
       android:radius="120px"
        />
</shape>

選中時的背景檔案shape_gradient_blue.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle"
    android:color="@color/text_blue"
    >
    <solid android:color="@color/text_blue" />
    <corners
      android:radius="120px"
        />
    <stroke
        android:dashGap="0.0dip"
        android:dashWidth="0.0dip"
        android:width="1px"
        android:color="@color/text_blue"
        />
</shape>

點選按鈕文字變顏色的效果，首先在res下新建一個color檔案

建立selector檔案selector_select_day.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">


    <item android:state_checked="true" android:color="@color/white"/>
    <!-- not selected -->
    <item android:color="@color/text_blue"/>


</selector>

至此大功告成
執行效果：