after popping up, window needs to be close to RadioGroup, not to the top of the screen.
layout:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:clipChildren="false"
    tools:context="com.de.activity.MainActivity">

    <RadioGroup
        android:id="@+id/rg_tabs"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:clipChildren="true"
        android:background="-sharpFFFFFF"
        android:orientation="horizontal">

        <RadioButton
            android:id="@+id/rb_home"
            android:layout_width="0dp"
            android:layout_height="50dp"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/home_button_selector"
            android:gravity="center"
            android:paddingTop="5dp"
            android:text=""
            android:textColor="@drawable/main_radiobutton_text_color_selector" />

        <RadioButton
            android:id="@+id/rb_channel"
            android:layout_width="0dp"
            android:layout_height="50dp"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/channel_button_selector"
            android:gravity="center"
            android:paddingTop="5dp"
            android:text=""
            android:textColor="@drawable/main_radiobutton_text_color_selector" />

        <View
            android:layout_width="0dp"
            android:layout_height="50dp"
            android:layout_gravity="bottom"
            android:layout_weight="1" />

        <RadioButton
            android:id="@+id/rb_discovery"
            android:layout_width="0dp"
            android:layout_height="50dp"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/discovery_button_selector"
            android:gravity="center"
            android:paddingTop="5dp"
            android:text=""
            android:textColor="@drawable/main_radiobutton_text_color_selector" />

        <RadioButton
            android:id="@+id/rb_mine"
            android:layout_width="0dp"
            android:layout_height="50dp"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/mine_button_selector"
            android:gravity="center"
            android:paddingTop="5dp"
            android:text=""
            android:textColor="@drawable/main_radiobutton_text_color_selector" />

    </RadioGroup>

    <View
        android:layout_above="@id/rg_tabs"
        style="@style/HorizontalLine"/>

    <FrameLayout
        android:id="@+id/fl_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@id/rg_tabs">

    </FrameLayout>

    <!---->
    <ImageView
        android:id="@+id/iv_switch_game_normal"
        android:layout_width="wrap_content"
        android:layout_height="70dp"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:src="@mipmap/king_honor" />

</RelativeLayout>

Class partial code:

   private void showTypeWindow() {
        View typeWindow = LayoutInflater.from(MainActivity.this).inflate(R.layout.window_type, null);
        mPopupWindow = new PopupWindow(typeWindow, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        mPopupWindow.setBackgroundDrawable(new BitmapDrawable());     //popupwindow
        mPopupWindow.setFocusable(true);
        //TODO:windowbutton
        int[] location = new int[2];
        mSwitchGameNormal.getLocationOnScreen(location);
        mPopupWindow.showAtLocation(mSwitchGameNormal, Gravity.NO_GRAVITY, location[0], location[1]-mPopupWindow.getHeight());
       // mPopupWindow.showAtLocation(mSwitchGameNormal, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 0, 0); //popupwindow
        WindowManager.LayoutParams lpType = getWindow().getAttributes(); // 
        lpType.alpha = 0.7f;
        getWindow().setAttributes(lpType);
        mPopupWindow.setOnDismissListener(new PopupWindow.OnDismissListener() {
            @Override
            public void onDismiss() {
                WindowManager.LayoutParams lp = getWindow().getAttributes();
                lp.alpha = 1f;
                getWindow().setAttributes(lp);
            }
        });
        TextView heroUnion = typeWindow.findViewById(R.id.rl_hero_union);
        TextView kingHonor = typeWindow.findViewById(R.id.rl_king_honor);
        TextView wildrnessAction = typeWindow.findViewById(R.id.rl_wilderness_action);
        heroUnion.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "", Toast.LENGTH_SHORT).show();
                mSwitchGameNormal.setImageResource(R.mipmap.hero_union);
                mPopupWindow.dismiss();
            }
        });
        kingHonor.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "", Toast.LENGTH_SHORT).show();
                mSwitchGameNormal.setImageResource(R.mipmap.king_honor);
                mPopupWindow.dismiss();
            }
        });
        wildrnessAction.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "", Toast.LENGTH_SHORT).show();
                mSwitchGameNormal.setImageResource(R.mipmap.wilderness_action);
                mPopupWindow.dismiss();
            }
        });
    }

desired effect: