No content in HideOrShowChartSeriesActivity yet

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

@@ -1,10 +1,18 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout
-        xmlns:android="http://schemas.android.com/apk/res/android"
-        xmlns:tools="http://schemas.android.com/tools"
+<android.support.constraint.ConstraintLayout 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"
         tools:context=".ChartsDemo.AdditionalContent.HideOrShowChartSeriesActivity">
 
+    <TextView
+            android:id="@+id/textView6"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="282dp"
+            android:text="暂无内容"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
 </android.support.constraint.ConstraintLayout>