Update demo fragment to support edge to edge.

Add convenience method to DemoUtils that will add a space to offset the bottom WindowInsets when needed.

Updated DemoLandingFragment to call this utils method as well.

PiperOrigin-RevId: 263622027

Author: wcshi

catalog/java/io/material/catalog/feature/DemoFragment.java

@@ -73,6 +73,8 @@ public View onCreateView(
     initDemoActionBar();
     demoContainer.addView(onCreateDemoView(layoutInflater, viewGroup, bundle));
 
+    ViewGroup children = (ViewGroup) demoContainer.getChildAt(0);
+    DemoUtils.addBottomSpaceInsetsIfNeeded(children, demoContainer);
     return view;
   }
 

catalog/java/io/material/catalog/feature/DemoLandingFragment.java

@@ -32,7 +32,6 @@
 import androidx.fragment.app.Fragment;
 import androidx.core.view.MarginLayoutParamsCompat;
 import androidx.core.view.MenuItemCompat;
-import androidx.core.view.ViewCompat;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.Toolbar;
 import android.view.LayoutInflater;
@@ -41,7 +40,6 @@
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
-import android.view.ViewGroup.LayoutParams;
 import android.view.ViewGroup.MarginLayoutParams;
 import android.widget.TextView;
 import dagger.android.support.DaggerFragment;
@@ -102,16 +100,7 @@ public View onCreateView(
     }
     additionalDemosSection.setVisibility(additionalDemos.isEmpty() ? View.GONE : View.VISIBLE);
 
-    View spacer = view.findViewById(R.id.spacer);
-    ViewCompat.setOnApplyWindowInsetsListener(
-        viewGroup,
-        (v, insets) -> {
-          LayoutParams lp = spacer.getLayoutParams();
-          lp.height = insets.getSystemWindowInsetBottom();
-          spacer.setVisibility(View.VISIBLE);
-          spacer.setLayoutParams(lp);
-          return ViewCompat.onApplyWindowInsets(v, insets);
-        });
+    DemoUtils.addBottomSpaceInsetsIfNeeded((ViewGroup) view, viewGroup);
     return view;
   }
 

catalog/java/io/material/catalog/feature/DemoUtils.java

@@ -18,9 +18,13 @@
 
 import android.app.Activity;
 import com.google.android.material.snackbar.Snackbar;
+import androidx.core.view.ViewCompat;
+import androidx.core.widget.NestedScrollView;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.ScrollView;
+import android.widget.Space;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -55,4 +59,34 @@ public static boolean showSnackbar(Activity activity, MenuItem menuItem) {
         .show();
     return true;
   }
+
+  public static void addBottomSpaceInsetsIfNeeded(
+      ViewGroup scrollableViewAncestor, ViewGroup viewGroupFitsSystemWindows) {
+    List<ScrollView> scrollViews =
+        DemoUtils.findViewsWithType(scrollableViewAncestor, ScrollView.class);
+    List<NestedScrollView> nestedScrollViews =
+        DemoUtils.findViewsWithType(scrollableViewAncestor, NestedScrollView.class);
+
+    ViewGroup scrollableContent = null;
+    if (!scrollViews.isEmpty()) {
+      scrollableContent = scrollViews.get(0);
+    } else if (!nestedScrollViews.isEmpty()) {
+      scrollableContent = nestedScrollViews.get(0);
+    }
+
+    if (scrollableContent != null && scrollableContent.getChildAt(0) instanceof ViewGroup) {
+      ViewGroup spaceParent = ((ViewGroup) scrollableContent.getChildAt(0));
+      Space space = new Space(scrollableViewAncestor.getContext());
+      space.setVisibility(View.GONE);
+      spaceParent.addView(space);
+
+      ViewCompat.setOnApplyWindowInsetsListener(
+          viewGroupFitsSystemWindows,
+          (v, insets) -> {
+            space.setVisibility(View.VISIBLE);
+            space.getLayoutParams().height = insets.getSystemWindowInsetBottom();
+            return insets;
+          });
+    }
+  }
 }

catalog/java/io/material/catalog/feature/res/layout/cat_demo_fragment.xml

@@ -22,7 +22,8 @@
 
   <com.google.android.material.appbar.AppBarLayout
       android:layout_width="match_parent"
-      android:layout_height="wrap_content">
+      android:layout_height="wrap_content"
+      android:fitsSystemWindows="true">
 
     <androidx.appcompat.widget.Toolbar
         android:id="@+id/toolbar"
@@ -31,8 +32,9 @@
         android:layout_height="wrap_content"/>
   </com.google.android.material.appbar.AppBarLayout>
 
-  <FrameLayout
+  <androidx.coordinatorlayout.widget.CoordinatorLayout
       android:id="@+id/cat_demo_fragment_container"
       android:layout_width="match_parent"
-      android:layout_height="match_parent"/>
+      android:layout_height="match_parent"
+      android:fitsSystemWindows="true"/>
 </LinearLayout>

catalog/java/io/material/catalog/feature/res/layout/cat_demo_landing_fragment.xml

@@ -88,12 +88,6 @@
       </LinearLayout>
 
       <include layout="@layout/cat_demo_landing_links_section"/>
-
-      <Space
-          android:id="@+id/spacer"
-          android:layout_height="0dp"
-          android:layout_width="match_parent"
-          android:visibility="gone"/>
     </LinearLayout>
   </androidx.core.widget.NestedScrollView>