@Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 this.requestWindowFeature(Window.FEATURE_NO_TITLE);
 this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
  WindowManager.LayoutParams.FLAG_FULLSCREEN);
 setContentView(R.layout.dialog_show_display_mode);
 WindowManager windowManager = getWindowManager();
 Display display = windowManager.getDefaultDisplay();
 WindowManager.LayoutParams params = getWindow().getAttributes();
// params.height = (int) (display.getHeight() * 0.3);
// params.width = (int) (display.getWidth() * 0.8);
 params.alpha = 1.0f;
 getWindow().setAttributes(params);
 getWindow().setGravity(Gravity.CENTER);
}

<?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:background="@color/white"
 android:orientation="vertical">

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="45dp">

 <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center"
  android:layout_marginLeft="20dp"
  android:text="语音球开启方式"
  android:textColor="@color/bg_black"
  android:textSize="20dp" />
 </LinearLayout>

 <View
 android:layout_width="match_parent"
 android:layout_height="1dp"
 android:background="@color/forget_password" />

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical">

 <LinearLayout
  android:id="@+id/display_dialog_intelligence_linner"
  android:layout_width="match_parent"
  android:layout_height="65dp"
  android:orientation="horizontal">

  <ImageView
  android:id="@+id/display_dialog_intelligence_iv"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center"
  android:src="@mipmap/abc_btn_radio_to_on_mtrl_000" />

  <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center"
  android:layout_marginLeft="10dp"
  android:text="智能显示"
  android:textColor="@color/colorGreen2" />
 </LinearLayout>

 <View
  android:layout_width="match_parent"
  android:layout_height="1dp"
  android:background="@color/forget_password" />

 <LinearLayout
  android:id="@+id/display_dialog_custom_linner"
  android:layout_width="match_parent"
  android:layout_height="65dp"
  android:orientation="horizontal">

  <ImageView
  android:id="@+id/display_dialog_custom_iv"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center"
  android:src="@mipmap/abc_btn_radio_to_on_mtrl_000" />

  <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center"
  android:layout_marginLeft="10dp"
  android:text="自定义显示"
  android:textColor="@color/colorGreen2" />
 </LinearLayout>
 </LinearLayout>
</LinearLayout>

<style name="activityTheme" parent="@android:style/Theme.Translucent.NoTitleBar.Fullscreen">
 <item name="android:windowFrame">@null</item><!--边框-->
 <item name="android:windowIsFloating">true</item><!--是否浮现在activity之上-->
 <item name="android:windowIsTranslucent">false</item><!--半透明-->
 <item name="android:windowNoTitle">true</item><!--无标题-->
 <item name="android:background">@android:color/transparent</item>
 <item name="android:windowBackground">@android:color/transparent</item><!--背景透明-->
 <item name="android:backgroundDimEnabled">true</item><!--模糊-->
 </style>

<activity
  android:name=".__activity.FloatWindowDialogActivity"
  android:screenOrientation="portrait"
  android:theme="@style/activityTheme" />