优化

app/src/main/res/layout/dialog_number_picker.xml

@@ -1,24 +1,13 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:background="@color/background">
 
-    <LinearLayout
-        android:layout_width="match_parent"
+    <NumberPicker
+        android:id="@+id/number_picker"
+        android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_gravity="center"
-        android:gravity="center"
-        tools:ignore="UselessParent">
+        android:layout_gravity="center" />
 
-        <NumberPicker
-            android:id="@+id/number_picker"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content">
-
-        </NumberPicker>
-
-    </LinearLayout>
-
-</LinearLayout>
+</FrameLayout>