drawable下新建selector型別的檔案
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_checked="true" android:drawable="@color/colorSelect"/>//選中時顏色
    <item android:state_checked="false" android:drawable="@color/colorNoSelect"
 
/>//未選中時顏色
    <item android:drawable="@color/colorNoSelect"/>//預設顏色

</selector>

//佈局中RadioGroup程式碼,,,

在每個RadioButton中引用,剛才寫的檔案,android:background="@drawable/radio_selector"

//給預設展示頁面的對應的RadioButton中設定預設選中,android:cheched="true"

<RadioGroup
android:id="@+id/radiogroup"
android:orientation="horizontal"
 
android:layout_width="match_parent"
android:layout_alignParentBottom="true"
android:layout_height="40dp">
    <RadioButton
android:id="@+id/home_button"
android:background="@drawable/radio_selector"
android:gravity="center"
android:layout_width="0dp"
android:button="@null"
android:layout_weight="1"
 
android:layout_height="match_parent"
android:text="首頁"/>
    <RadioButton
android:id="@+id/zixuan_button"
android:background="@drawable/radio_selector"
android:gravity="center"
android:layout_width="0dp"
android:button="@null"
android:layout_weight="1"
android:layout_height="match_parent"
android:text="自選"/>
    <RadioButton
android:id="@+id/hangqing_button"
android:background="@drawable/radio_selector"
android:gravity="center"
android:layout_width="0dp"
android:button="@null"
android:layout_weight="1"
android:layout_height="match_parent"
android:text="行情"/>
    <RadioButton
android:id="@+id/zixun_button"
android:background="@drawable/radio_selector"
android:checked="true"
android:gravity="center"
android:layout_width="0dp"
android:button="@null"
android:layout_weight="1"
android:layout_height="match_parent"
android:text="資訊"/>
    <RadioButton
android:id="@+id/jiaoyi"
android:background="@drawable/radio_selector"
android:gravity="center"
android:layout_width="0dp"
android:button="@null"
android:layout_weight="1"
android:layout_height="match_parent"
android:text="交易"/>
</RadioGroup>