[NavigationRail] Add item spacing attribute

PiperOrigin-RevId: 639835301
material-components · Jun 5, 2024 · 99e8044 · 99e8044
1 parent abb6e91
commit 99e8044
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Showing 7 changed files with 58 additions and 5 deletions.
diff --git a/docs/components/NavigationRail.md b/docs/components/NavigationRail.md
@@ -322,6 +322,9 @@ for more attributes.
 **Ripple (active)** | `app:itemRippleColor` | `setItemRippleColor`<br/>`getItemRippleColor` | `?attr/colorPrimary` at 12% (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigation/res/color/mtrl_navigation_bar_ripple_color.xml))
 **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`
+
+**Note:** If there's not enough room, `itemMinHeight` and `itemSpacing` may not be respected in order to fit the items.
 
 #### Active indicator attributes
 

diff --git a/lib/java/com/google/android/material/internal/FlowLayout.java b/lib/java/com/google/android/material/internal/FlowLayout.java
@@ -70,7 +70,7 @@ private void loadFromAttributes(@NonNull Context context, @Nullable AttributeSet
  final TypedArray array =
  context.getTheme().obtainStyledAttributes(attrs, R.styleable.FlowLayout, 0, 0);
  lineSpacing = array.getDimensionPixelSize(R.styleable.FlowLayout_lineSpacing, 0);
- itemSpacing = array.getDimensionPixelSize(R.styleable.FlowLayout_itemSpacing, 0);
+ itemSpacing = array.getDimensionPixelSize(R.styleable.FlowLayout_horizontalItemSpacing, 0);
  array.recycle();
  }
 

diff --git a/lib/java/com/google/android/material/internal/res/values/attrs.xml b/lib/java/com/google/android/material/internal/res/values/attrs.xml
@@ -47,7 +47,7 @@
  <!-- Do not expose publicly, FlowLayout (private class) that is the parent for ChipGroup (public), which has its own public spacing attributes. -->
  <declare-styleable name="FlowLayout">
  <!-- Horizontal spacing between two items being laid out. -->
- <attr name="itemSpacing" format="dimension"/>
+ <attr name="horizontalItemSpacing" format="dimension"/>
  <!-- Vertical Spacing between two lines of items being laid out. -->
  <attr name="lineSpacing" format="dimension"/>
  </declare-styleable>

diff --git a/lib/java/com/google/android/material/navigationrail/NavigationRailMenuView.java b/lib/java/com/google/android/material/navigationrail/NavigationRailMenuView.java
@@ -39,6 +39,7 @@
 public class NavigationRailMenuView extends NavigationBarMenuView {
 
  @Px private int itemMinimumHeight = NO_ITEM_MINIMUM_HEIGHT;
+ @Px private int itemSpacing = 0;
  private final FrameLayout.LayoutParams layoutParams =
  new FrameLayout.LayoutParams(MATCH_PARENT, WRAP_CONTENT);
 
@@ -72,13 +73,26 @@ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
  final int count = getChildCount();
  final int width = right - left;
+ int visibleCount = 0;
+ int childrenHeight = 0;
+ for (int i = 0; i < count; i++) {
+ final View child = getChildAt(i);
+ if (child.getVisibility() != GONE) {
+ childrenHeight += child.getMeasuredHeight();
+ visibleCount += 1;
+ }
+ }
+ int spacing =
+ visibleCount <= 1
+ ? 0
+ : max(0, min((getMeasuredHeight() - childrenHeight) / (visibleCount - 1), itemSpacing));
  int used = 0;
  for (int i = 0; i < count; i++) {
  final View child = getChildAt(i);
  if (child.getVisibility() != GONE) {
  int childHeight = child.getMeasuredHeight();
  child.layout(/* l= */ 0, used, width, childHeight + used);
- used += childHeight;
+ used += childHeight + spacing;
  }
  }
  }
@@ -129,15 +143,19 @@ private int measureSharedChildHeights(
  }
 
  int childCount = getChildCount();
+ int visibleChildCount = 0;
  int totalHeight = 0;
  for (int i = 0; i < childCount; i++) {
  final View child = getChildAt(i);
+ if (child.getVisibility() == VISIBLE) {
+ visibleChildCount += 1;
+ }
  if (child != selectedView) {
  totalHeight += measureChildHeight(child, widthMeasureSpec, childHeightSpec);
  }
  }
 
- return totalHeight;
+ return totalHeight + max(0, visibleChildCount - 1) * itemSpacing;
  }
 
  private int measureChildHeight(View child, int widthMeasureSpec, int heightMeasureSpec) {
@@ -172,6 +190,18 @@ public int getItemMinimumHeight() {
  return this.itemMinimumHeight;
  }
 
+ public void setItemSpacing(@Px int spacing) {
+ if (this.itemSpacing != spacing) {
+ this.itemSpacing = spacing;
+ requestLayout();
+ }
+ }
+
+ @Px
+ public int getItemSpacing() {
+ return this.itemSpacing;
+ }
+
  boolean isTopGravity() {
  return (layoutParams.gravity & Gravity.VERTICAL_GRAVITY_MASK) == Gravity.TOP;
  }

diff --git a/lib/java/com/google/android/material/navigationrail/NavigationRailView.java b/lib/java/com/google/android/material/navigationrail/NavigationRailView.java
@@ -189,6 +189,8 @@ public NavigationRailView(
  AnimationUtils.lerp(getItemPaddingBottom(), largeFontBottomPadding, progress);
  setItemPaddingTop(Math.round(topPadding));
  setItemPaddingBottom(Math.round(bottomPadding));
+ setItemSpacing(
+ attributes.getDimensionPixelSize(R.styleable.NavigationRailView_itemSpacing, 0));
 
  attributes.recycle();
 
@@ -358,6 +360,20 @@ public void setItemMinimumHeight(@Px int minHeight) {
  menuView.setItemMinimumHeight(minHeight);
  }
 
+ /**
+ * Set the padding in between the navigation rail menu items.
+ */
+ public void setItemSpacing(@Px int itemSpacing) {
+ getNavigationRailMenuView().setItemSpacing(itemSpacing);
+ }
+
+ /**
+ * Get the padding in between the navigation rail menu items.
+ */
+ public int getItemSpacing() {
+ return getNavigationRailMenuView().getItemSpacing();
+ }
+
  @Override
  public int getMaxItemCount() {
  return MAX_ITEM_COUNT;

diff --git a/lib/java/com/google/android/material/navigationrail/res-public/values/public.xml b/lib/java/com/google/android/material/navigationrail/res-public/values/public.xml
@@ -22,6 +22,7 @@
  <public name="menuGravity" type="attr"/>
  <public name="contentMarginTop" type="attr"/>
  <public name="headerMarginBottom" type="attr"/>
+ <public name="itemSpacing" type="attr"/>
  <public name="Widget.MaterialComponents.NavigationRailView" type="style"/>
  <public name="Widget.MaterialComponents.NavigationRailView.Compact" type="style"/>
  <public name="Widget.MaterialComponents.NavigationRailView.Colored" type="style"/>

diff --git a/lib/java/com/google/android/material/navigationrail/res/values/attrs.xml b/lib/java/com/google/android/material/navigationrail/res/values/attrs.xml
@@ -28,7 +28,10 @@
  <attr name="headerMarginBottom" format="dimension"/>
  <!-- The top margin of the content of the navigation rail. -->
  <attr name="contentMarginTop" format="dimension"/>
- <!-- Specifies how the navigation rail destinations should be aligned as a group. -->
+ <!-- The spacing between the navigation rail items. -->
+ <attr name="itemSpacing" format="dimension"/>
+
+ <!-- Specifies how the navigation rail destinations should be aligned as a group. -->
  <attr name="menuGravity">
  <!-- Navigation rail destinations will be aligned as a group at the top. This is the default behavior. -->
  <!-- Gravity.TOP | Gravity.CENTER_HORIZONTAL-->