[NavigationBar] Add item gravity attribute and setter/getter

PiperOrigin-RevId: 660062964

Author: imhappi

docs/components/BottomNavigation.md

@@ -276,7 +276,7 @@ The following is an anatomy diagram for the bottom navigation bar:
 **Ripple (inactive)**     | `app:itemRippleColor`     | `setItemRippleColor`<br/>`getItemRippleColor`         | Variations of `?attr/colorPrimary` and `?attr/colorOnSurfaceVariant` (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/bottomnavigation/res/color/m3_navigation_bar_ripple_color_selector.xml))
 **Ripple (active)**       | "                         | "                                                     | Variations of `?attr/colorPrimary` (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/bottomnavigation/res/color/m3_navigation_bar_ripple_color_selector.xml))
 **Label visibility mode** | `app:labelVisibilityMode` | `setLabelVisibilityMode`<br/>`getLabelVisibilityMode` | `LABEL_VISIBILITY_AUTO`
-
+**Item Gravity**          | `app:itemGravity`         | `setItemGravity`<br/>`getItemGravity`                 | `TOP_CENTER`
 
 #### Active indicator attributes
 

docs/components/NavigationRail.md

@@ -323,6 +323,7 @@ for more attributes.
 **Label visibility mode** | `app:labelVisibilityMode` | `setLabelVisibilityMode`<br/>`getLabelVisibilityMode` | `LABEL_VISIBILITY_AUTO`
 **Item minimum height**   | `app:itemMinHeight`       | `setItemMinimumHeight`<br/>`getItemMinimumHeight`     | `NO_ITEM_MINIMUM_HEIGHT`
 **Item spacing**          | `app:itemSpacing`         | `setItemSpacing`<br/>`getItemSpacing`                 | `0dp`
+**Item Gravity**          | `app:itemGravity`         | `setItemGravity`<br/>`getItemGravity`                 | `TOP_CENTER`
 
 **Note:** If there's not enough room, `itemMinHeight` and `itemSpacing` may not be respected in order to fit the items.
 

lib/java/com/google/android/material/navigation/NavigationBarItemView.java

@@ -74,6 +74,7 @@
 import com.google.android.material.badge.BadgeUtils;
 import com.google.android.material.internal.BaselineLayout;
 import com.google.android.material.motion.MotionUtils;
+import com.google.android.material.navigation.NavigationBarView.ItemGravity;
 import com.google.android.material.navigation.NavigationBarView.ItemIconGravity;
 import com.google.android.material.resources.MaterialResources;
 import com.google.android.material.ripple.RippleUtils;
@@ -147,6 +148,7 @@ public abstract class NavigationBarItemView extends FrameLayout implements MenuV
 
   @ItemIconGravity private int itemIconGravity;
   private int badgeFixedEdge = BadgeDrawable.BADGE_FIXED_EDGE_START;
+  @ItemGravity private int itemGravity = NavigationBarView.ITEM_GRAVITY_TOP_CENTER;
 
   public NavigationBarItemView(@NonNull Context context) {
     super(context);
@@ -292,16 +294,12 @@ public void setLabelVisibilityMode(@NavigationBarView.LabelVisibility int mode)
   }
 
   private void updateItemIconGravity() {
-    int gravity = Gravity.CENTER_HORIZONTAL | Gravity.TOP;
     int sideMargin = 0;
     int labelGroupTopMargin = activeIndicatorLabelPadding;
     int labelGroupSideMargin = 0;
     int sidePadding = 0;
-    int contentGravity = Gravity.CENTER;
     badgeFixedEdge = BadgeDrawable.BADGE_FIXED_EDGE_START;
     if (itemIconGravity == ITEM_ICON_GRAVITY_START) {
-      gravity = Gravity.CENTER;
-      contentGravity = Gravity.START | Gravity.CENTER_VERTICAL;
       sideMargin =
           getResources()
               .getDimensionPixelSize(R.dimen.m3_expressive_navigation_item_leading_trailing_space);
@@ -318,12 +316,11 @@ private void updateItemIconGravity() {
       contentContainer.addView(labelGroup);
     }
     FrameLayout.LayoutParams contentContainerLp = (LayoutParams) contentContainer.getLayoutParams();
-    contentContainerLp.gravity = gravity;
+    contentContainerLp.gravity = itemGravity;
     FrameLayout.LayoutParams innerContentLp =
         (LayoutParams) innerContentContainer.getLayoutParams();
     innerContentLp.leftMargin = sideMargin;
     innerContentLp.rightMargin = sideMargin;
-    innerContentLp.gravity = contentGravity;
     LinearLayout.LayoutParams labelGroupLp =
         (LinearLayout.LayoutParams) labelGroup.getLayoutParams();
     labelGroupLp.rightMargin =
@@ -466,9 +463,7 @@ private void setLayoutConfigurationIconAndLabel(
         contentContainer,
         itemIconGravity == ITEM_ICON_GRAVITY_TOP ? (int) (itemPaddingTop + topMarginShift) : 0,
         0,
-        itemIconGravity == ITEM_ICON_GRAVITY_TOP
-            ? Gravity.CENTER_HORIZONTAL | Gravity.TOP
-            : Gravity.CENTER);
+        itemGravity);
     setViewMarginAndGravity(
         innerContentContainer,
         0,
@@ -484,7 +479,8 @@ private void setLayoutConfigurationIconAndLabel(
   }
 
   private void setLayoutConfigurationIconOnly() {
-    setViewMarginAndGravity(contentContainer, itemPaddingTop, itemPaddingTop, Gravity.CENTER);
+    setViewMarginAndGravity(contentContainer, itemPaddingTop, itemPaddingTop,
+        itemIconGravity == ITEM_ICON_GRAVITY_TOP ? Gravity.CENTER : itemGravity);
     setViewMarginAndGravity(innerContentContainer, 0, 0, Gravity.CENTER);
     updateViewPaddingBottom(labelGroup, 0);
     labelGroup.setVisibility(GONE);
@@ -870,6 +866,14 @@ public void setActiveIndicatorEnabled(boolean enabled) {
     requestLayout();
   }
 
+  /**
+   * Set the gravity of the item.
+   */
+  public void setItemGravity(@ItemGravity int itemGravity) {
+    this.itemGravity = itemGravity;
+    requestLayout();
+  }
+
   /**
    * Set the desired width of the active indicator.
    *

lib/java/com/google/android/material/navigation/NavigationBarMenuView.java

@@ -109,6 +109,7 @@ public abstract class NavigationBarMenuView extends ViewGroup implements MenuVie
 
   private int itemActiveIndicatorMarginHorizontal;
   private int itemActiveIndicatorExpandedMarginHorizontal;
+  private int itemGravity = NavigationBarView.ITEM_GRAVITY_TOP_CENTER;
   private ShapeAppearanceModel itemActiveIndicatorShapeAppearance;
   private boolean itemActiveIndicatorResizeable = false;
   private ColorStateList itemActiveIndicatorColor;
@@ -475,6 +476,30 @@ public void setItemActiveIndicatorHeight(@Px int height) {
     }
   }
 
+  /**
+   * Sets the navigation items' layout gravity.
+   *
+   * @param itemGravity the layout {@link android.view.Gravity} of the item
+   * @see #getItemGravity()
+   */
+  public void setItemGravity(int itemGravity) {
+    this.itemGravity = itemGravity;
+    if (buttons != null) {
+      for (NavigationBarItemView item : buttons) {
+        item.setItemGravity(itemGravity);
+      }
+    }
+  }
+
+  /**
+   * Returns the navigation items' layout gravity.
+   *
+   * @see #setItemGravity(int)
+   */
+  public int getItemGravity() {
+    return itemGravity;
+  }
+
   /**
    * Get the width of the selected item's active indicator when expanded.
    *
@@ -886,6 +911,7 @@ public void buildMenuView() {
       child.setActiveIndicatorExpandedWidth(itemActiveIndicatorExpandedWidth);
       child.setActiveIndicatorExpandedHeight(itemActiveIndicatorExpandedHeight);
       child.setActiveIndicatorMarginHorizontal(itemActiveIndicatorMarginHorizontal);
+      child.setItemGravity(itemGravity);
       child.setActiveIndicatorExpandedMarginHorizontal(itemActiveIndicatorExpandedMarginHorizontal);
       child.setActiveIndicatorDrawable(createItemActiveIndicatorDrawable());
       child.setActiveIndicatorResizeable(itemActiveIndicatorResizeable);
@@ -946,6 +972,7 @@ public void updateMenuView() {
       presenter.setUpdateSuspended(true);
       buttons[i].setLabelVisibilityMode(labelVisibilityMode);
       buttons[i].setItemIconGravity(itemIconGravity);
+      buttons[i].setItemGravity(itemGravity);
       buttons[i].setShifting(shifting);
       buttons[i].initialize((MenuItemImpl) menu.getItem(i), 0);
       presenter.setUpdateSuspended(false);

lib/java/com/google/android/material/navigation/NavigationBarView.java

@@ -36,6 +36,7 @@
 import androidx.appcompat.view.menu.MenuView;
 import androidx.appcompat.widget.TintTypedArray;
 import android.util.AttributeSet;
+import android.view.Gravity;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
@@ -131,6 +132,26 @@ public abstract class NavigationBarView extends FrameLayout {
   /** Icon is placed at the top of the item */
   public static final int ITEM_ICON_GRAVITY_START = 1;
 
+  /**
+   * Navigation Bar Item gravity enum to control where the item is in its container.
+   *
+   * @hide
+   */
+  @RestrictTo(LIBRARY_GROUP)
+  @IntDef(value = {ITEM_GRAVITY_TOP_CENTER, ITEM_GRAVITY_CENTER, ITEM_GRAVITY_START_CENTER})
+  @Retention(RetentionPolicy.SOURCE)
+  public @interface ItemGravity {}
+
+  /** Item is placed at the top center of its container */
+  public static final int ITEM_GRAVITY_TOP_CENTER = Gravity.TOP | Gravity.CENTER_HORIZONTAL;
+
+  /** Item is placed at the center of its container */
+  public static final int ITEM_GRAVITY_CENTER = Gravity.CENTER;
+
+  /** Item is placed at the start center of its container */
+  public static final int ITEM_GRAVITY_START_CENTER = Gravity.START | Gravity.CENTER_VERTICAL;
+
+
   /**
    * Navigation Bar Item icon gravity enum to control which item configuration to display.
    *
@@ -274,6 +295,9 @@ public NavigationBarView(
         attributes.getInteger(
             R.styleable.NavigationBarView_itemIconGravity,
             NavigationBarView.ITEM_ICON_GRAVITY_TOP));
+    setItemGravity(
+        attributes.getInteger(
+            R.styleable.NavigationBarView_itemGravity, NavigationBarView.ITEM_GRAVITY_TOP_CENTER));
 
     int itemBackground = attributes.getResourceId(R.styleable.NavigationBarView_itemBackground, 0);
     if (itemBackground != 0) {
@@ -740,6 +764,29 @@ public void setItemActiveIndicatorMarginHorizontal(@Px int horizontalMargin) {
     menuView.setItemActiveIndicatorMarginHorizontal(horizontalMargin);
   }
 
+  /**
+   * Sets the navigation items' layout gravity.
+   *
+   * @param itemGravity the layout {@link android.view.Gravity} of the item
+   * @see #getItemGravity()
+   */
+  public void setItemGravity(@ItemGravity int itemGravity) {
+    if (menuView.getItemIconGravity() != itemGravity) {
+      menuView.setItemGravity(itemGravity);
+      presenter.updateMenuView(false);
+    }
+  }
+
+  /**
+   * Returns the navigation items' layout gravity.
+   *
+   * @see #setItemGravity(int)
+   */
+  @ItemGravity
+  public int getItemGravity() {
+    return menuView.getItemGravity();
+  }
+
   /**
    * Get the width of an item's active indicator when it is expanded to wrap the item content, ie.
    * when it is in the {@link ItemIconGravity#ITEM_ICON_GRAVITY_START} configuration.

lib/java/com/google/android/material/navigation/res-public/values/public.xml

@@ -56,6 +56,7 @@
   <public name="itemPaddingBottom" type="attr"/>
   <public name="itemActiveIndicatorStyle" type="attr"/>
   <public name="itemIconGravity" type="attr"/>
+  <public name="itemGravity" type="attr"/>
   <public name="marginHorizontal" type="attr"/>
   <public name="expandedWidth" type="attr"/>
   <public name="expandedHeight" type="attr"/>

lib/java/com/google/android/material/navigation/res/values/attrs.xml

@@ -88,6 +88,16 @@
       <enum name="start" value="1"/>
     </attr>
 
+    <!-- The gravity of the item within the Navigation Bar -->
+    <attr name="itemGravity">
+      <!-- Gravity.TOP | Gravity.CENTER_HORIZONTAL -->
+      <enum name="top_center" value="49"/>
+      <!-- Gravity.CENTER-->
+      <enum name="center" value="17"/>
+      <!-- Gravity.START | Gravity.CENTER_VERTICAL -->
+      <enum name="start_center" value="8388627"/>
+    </attr>
+
     <!-- Measure the item's bottom padding from the baseline of the label, not the bottom of its
          view. -->
     <attr name="measureBottomPaddingFromLabelBaseline" format="boolean"/>