[BottomNavigationView][NavigationRailView] Modifying NavigationBarVie…

…w to match more to specs and restructuring layout to prepare for expressive changes

Changes:
- minHeight for BottomNavigationView is actually a minimum height, not an exact height; the bar height now wraps content properly
- For BottomNavigationView, bottom item padding now counts from the bottom of the label group instead of from the lowest label baseline. The label TextViews also have a min height of the line height supplied by the provided TextAppearance. This aligns with our m3 specs
- Structural changes in navigation item layouts. Previously the label and the icon were not aware of each other in a FrameLayout and could potentially overlap; this is no longer the case as they are in a LinearLayout
- padding between icon and label is 4dp as per specs
- Centering logic changed to center the icon and label as a group, not separately
PiperOrigin-RevId: 635922505

lib/java/com/google/android/material/bottomnavigation/BottomNavigationMenuView.java

@@ -77,7 +77,7 @@ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  tempChildWidths.clear();
 
  int parentHeight = MeasureSpec.getSize(heightMeasureSpec);
- final int heightSpec = MeasureSpec.makeMeasureSpec(parentHeight, MeasureSpec.EXACTLY);
+ final int heightSpec = MeasureSpec.makeMeasureSpec(parentHeight, MeasureSpec.AT_MOST);
 
  if (isShifting(getLabelVisibilityMode(), visibleCount)
  && isItemHorizontalTranslationEnabled()) {
@@ -131,6 +131,7 @@ && isItemHorizontalTranslationEnabled()) {
  }
 
  int totalWidth = 0;
+ int maxHeight = 0;
  for (int i = 0; i < totalCount; i++) {
  final View child = getChildAt(i);
  if (child.getVisibility() == GONE) {
@@ -141,9 +142,10 @@ && isItemHorizontalTranslationEnabled()) {
  ViewGroup.LayoutParams params = child.getLayoutParams();
  params.width = child.getMeasuredWidth();
  totalWidth += child.getMeasuredWidth();
+ maxHeight = Math.max(maxHeight, child.getMeasuredHeight());
  }
 
- setMeasuredDimension(totalWidth, parentHeight);
+ setMeasuredDimension(totalWidth, Math.max(maxHeight, getSuggestedMinimumHeight()));
  }
 
  @Override

lib/java/com/google/android/material/bottomnavigation/BottomNavigationView.java

@@ -19,7 +19,6 @@
 import com.google.android.material.R;
 
 import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP;
-import static java.lang.Math.min;
 
 import android.content.Context;
 import android.os.Build.VERSION;
@@ -168,6 +167,13 @@ public WindowInsetsCompat onApplyWindowInsets(
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  int minHeightSpec = makeMinHeightSpec(heightMeasureSpec);
  super.onMeasure(widthMeasureSpec, minHeightSpec);
+ if (MeasureSpec.getMode(heightMeasureSpec) != MeasureSpec.EXACTLY) {
+ setMeasuredDimension(
+ getMeasuredWidth(),
+ Math.max(
+ getMeasuredHeight(),
+ getSuggestedMinimumHeight() + getPaddingTop() + getPaddingBottom()));
+ }
  }
 
  private int makeMinHeightSpec(int measureSpec) {
@@ -176,7 +182,7 @@ private int makeMinHeightSpec(int measureSpec) {
  minHeight += getPaddingTop() + getPaddingBottom();
 
  return MeasureSpec.makeMeasureSpec(
- min(MeasureSpec.getSize(measureSpec), minHeight), MeasureSpec.EXACTLY);
+ Math.max(MeasureSpec.getSize(measureSpec), minHeight), MeasureSpec.AT_MOST);
  }
 
  return measureSpec;

lib/java/com/google/android/material/bottomnavigation/res/layout/design_bottom_navigation_item.xml

@@ -15,53 +15,65 @@
  ~ limitations under the License.
  -->
 <merge xmlns:android="http://schemas.android.com/apk/res/android">
-
- <FrameLayout
- android:id="@id/navigation_bar_item_icon_container"
+ <LinearLayout
+ android:id="@id/navigation_bar_item_content_container"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
- android:layout_gravity="center_horizontal"
+ android:layout_gravity="top|center_horizontal"
+ android:clipChildren="false"
+ android:duplicateParentState="true"
+ android:gravity="center"
  android:layout_marginTop="@dimen/design_bottom_navigation_margin"
- android:layout_marginBottom="@dimen/design_bottom_navigation_margin"
- android:duplicateParentState="true">
- <View
- android:id="@id/navigation_bar_item_active_indicator_view"
- android:layout_width="0dp"
- android:layout_height="0dp"
- android:layout_gravity="center" />
- <ImageView
- android:id="@id/navigation_bar_item_icon_view"
- android:layout_width="24dp"
- android:layout_height="24dp"
+ android:orientation="vertical">
+ <FrameLayout
+ android:id="@id/navigation_bar_item_icon_container"
+ android:layout_width="wrap_content"
+ android:layout_height="wrap_content"
  android:layout_gravity="center"
- android:contentDescription="@null"
- android:duplicateParentState="true"/>
- </FrameLayout>
- <com.google.android.material.internal.BaselineLayout
+ android:duplicateParentState="true">
+ <View
+ android:id="@id/navigation_bar_item_active_indicator_view"
+ android:layout_width="0dp"
+ android:layout_height="0dp"
+ android:layout_gravity="center" />
+ <ImageView
+ android:id="@id/navigation_bar_item_icon_view"
+ android:layout_width="@dimen/design_bottom_navigation_icon_size"
+ android:layout_height="@dimen/design_bottom_navigation_icon_size"
+ android:layout_gravity="center"
+ android:contentDescription="@null"
+ android:duplicateParentState="true" />
+ </FrameLayout>
+ <com.google.android.material.internal.BaselineLayout
  android:id="@id/navigation_bar_item_labels_group"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
- android:layout_gravity="bottom|center_horizontal"
- android:paddingBottom="@dimen/design_bottom_navigation_label_padding"
+ android:paddingBottom="@dimen/m3_bottom_nav_item_padding_bottom"
  android:clipChildren="false"
  android:clipToPadding="false"
+ android:layout_gravity="center"
  android:duplicateParentState="true">
- <TextView
+  <TextView
  android:id="@id/navigation_bar_item_small_label_view"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:duplicateParentState="true"
  android:ellipsize="end"
  android:maxLines="1"
- android:textSize="@dimen/design_bottom_navigation_text_size"/>
- <TextView
+ android:includeFontPadding="false"
+ android:gravity="center_vertical"
+ android:textSize="@dimen/design_bottom_navigation_text_size" />
+ <TextView
  android:id="@id/navigation_bar_item_large_label_view"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:duplicateParentState="true"
  android:ellipsize="end"
  android:maxLines="1"
+ android:gravity="center_vertical"
+ android:includeFontPadding="false"
  android:textSize="@dimen/design_bottom_navigation_active_text_size"
- android:visibility="invisible"/>
- </com.google.android.material.internal.BaselineLayout>
+ android:visibility="invisible" />
+ </com.google.android.material.internal.BaselineLayout>
+ </LinearLayout>
 </merge>

lib/java/com/google/android/material/bottomnavigation/res/values/styles.xml

@@ -26,7 +26,8 @@
  <item name="itemIconSize">@dimen/design_bottom_navigation_icon_size</item>
  <item name="labelVisibilityMode">auto</item>
  <item name="itemPaddingTop">@dimen/design_bottom_navigation_margin</item>
- <item name="itemPaddingBottom">@dimen/design_bottom_navigation_label_padding</item>
+ <item name="itemPaddingBottom">0dp</item>
+ <item name="activeIndicatorLabelPadding">1dp</item>
  <item name="itemActiveIndicatorStyle">@null</item>
  <item name="android:minHeight">@dimen/design_bottom_navigation_height</item>
  </style>
@@ -80,6 +81,7 @@
  <item name="android:minHeight">@dimen/m3_bottom_nav_min_height</item>
  <item name="materialThemeOverlay">@style/ThemeOverlay.Material3.BottomNavigationView</item>
  <item name="shapeAppearance">@style/ShapeAppearance.M3.Comp.NavigationBar.Container.Shape</item>
+ <item name="activeIndicatorLabelPadding">@dimen/m3_navigation_item_active_indicator_label_padding</item>
  </style>
 
  <style name="Widget.Material3.BottomNavigationView" parent="Base.Widget.Material3.BottomNavigationView">

lib/java/com/google/android/material/internal/BaselineLayout.java

@@ -22,14 +22,18 @@
 import android.view.ViewGroup;
 
 /**
- * A simple ViewGroup that aligns all the views inside on a baseline. Note: bottom padding for this
- * view will be measured starting from the baseline.
+ * A simple ViewGroup that aligns all the views inside on a baseline.
+ *
+ * <p>If {@link BaselineLayout#measurePaddingFromBaseline} is true, bottom padding for this view
+ * will be measured starting from the baseline.
  *
  * @hide
  */
 public class BaselineLayout extends ViewGroup {
  private int baseline = -1;
 
+ private boolean measurePaddingFromBaseline;
+
  public BaselineLayout(Context context) {
  super(context, null, 0);
  }
@@ -42,13 +46,19 @@ public BaselineLayout(Context context, AttributeSet attrs, int defStyleAttr) {
  super(context, attrs, defStyleAttr);
  }
 
+ // TODO(b/338647654): We can remove this once navigation rail is updated to current specs
+ public void setMeasurePaddingFromBaseline(boolean measurePaddingFromBaseline) {
+ this.measurePaddingFromBaseline = measurePaddingFromBaseline;
+ }
+
  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  final int count = getChildCount();
  int maxWidth = 0;
  int maxHeight = 0;
  int maxChildBaseline = -1;
  int maxChildDescent = -1;
+ int maxMeasuredHeight = 0;
  int childState = 0;
 
  for (int i = 0; i < count; i++) {
@@ -58,6 +68,7 @@ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  }
 
  measureChild(child, widthMeasureSpec, heightMeasureSpec);
+ maxMeasuredHeight = Math.max(maxMeasuredHeight, child.getMeasuredHeight());
  final int baseline = child.getBaseline();
  if (baseline != -1) {
  maxChildBaseline = Math.max(maxChildBaseline, baseline);
@@ -68,11 +79,15 @@ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  childState = View.combineMeasuredStates(childState, child.getMeasuredState());
  }
  if (maxChildBaseline != -1) {
- maxChildDescent = Math.max(maxChildDescent, getPaddingBottom());
- maxHeight = Math.max(maxHeight, maxChildBaseline + maxChildDescent);
+ if (measurePaddingFromBaseline) {
+ maxChildDescent = Math.max(maxChildDescent, getPaddingBottom());
+ maxHeight = Math.max(maxHeight, maxChildBaseline + maxChildDescent);
+ }
  this.baseline = maxChildBaseline;
  }
- maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight());
+ maxHeight = Math.max(
+ measurePaddingFromBaseline ? maxHeight : maxMeasuredHeight + getPaddingBottom(),
+ getSuggestedMinimumHeight());
  maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth());
  setMeasuredDimension(
  View.resolveSizeAndState(maxWidth, widthMeasureSpec, childState),