[CollapsingToolbarLayout] Allow application to Set ellipsis to Title in CollapsingToolBar

catalog/java/io/material/catalog/topappbar/TopAppBarCollapsingLargeMiddleEllipsizeDemoFragment.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.material.catalog.topappbar;
+
+import androidx.annotation.LayoutRes;
+
+import io.material.catalog.R;
+
+/** A fragment that displays a large collapsing Top App Bar demo for the Catalog app. */
+public class TopAppBarCollapsingLargeMiddleEllipsizeDemoFragment extends BaseTopAppBarCollapsingDemoFragment {
+
+  @LayoutRes
+  protected int getCollapsingToolbarLayoutResId() {
+    return R.layout.cat_topappbar_collapsing_large_middle_ellipsize_fragment;
+  }
+}

catalog/java/io/material/catalog/topappbar/TopAppBarFragment.java

@@ -109,6 +109,12 @@ public Fragment createFragment() {
             return new TopAppBarCollapsingLargeDemoFragment();
           }
         },
+        new Demo(R.string.cat_topappbar_collapsing_large_middle_ellipsize_title) {
+          @Override
+          public Fragment createFragment() {
+            return new TopAppBarCollapsingLargeMiddleEllipsizeDemoFragment();
+          }
+        },
         new Demo(R.string.cat_topappbar_collapsing_multiline_title) {
           @Override
           public Fragment createFragment() {

catalog/java/io/material/catalog/topappbar/res/layout/cat_topappbar_collapsing_large_middle_ellipsize_fragment.xml

@@ -0,0 +1,57 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Copyright 2017 The Android Open Source Project
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+      https://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+  -->
+<androidx.coordinatorlayout.widget.CoordinatorLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:id="@+id/coordinator"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+  <com.google.android.material.appbar.AppBarLayout
+      android:id="@+id/appbarlayout"
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"
+      android:fitsSystemWindows="true">
+
+    <com.google.android.material.appbar.CollapsingToolbarLayout
+        style="?attr/collapsingToolbarLayoutLargeStyle"
+        android:id="@+id/collapsingtoolbarlayout"
+        android:layout_width="match_parent"
+        android:layout_height="?attr/collapsingToolbarLayoutLargeSize"
+        app:layout_scrollFlags="scroll|exitUntilCollapsed|snap"
+        app:titleTextEllipsize="middle">
+
+      <androidx.appcompat.widget.Toolbar
+          android:id="@+id/toolbar"
+          style="?attr/catalogToolbarWithCloseButtonStyle"
+          android:layout_width="match_parent"
+          android:layout_height="?attr/actionBarSize"
+          android:elevation="0dp"
+          app:layout_collapseMode="pin"
+          app:title="Large Collapsing Toolbar Title Ellipsize test"/>
+    </com.google.android.material.appbar.CollapsingToolbarLayout>
+  </com.google.android.material.appbar.AppBarLayout>
+
+  <androidx.core.widget.NestedScrollView
+      android:layout_width="match_parent"
+      android:layout_height="match_parent"
+      app:layout_behavior="@string/appbar_scrolling_view_behavior">
+
+    <include layout="@layout/cat_topappbar_filler_text_view"/>
+  </androidx.core.widget.NestedScrollView>
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>

catalog/java/io/material/catalog/topappbar/res/values/strings.xml

@@ -24,6 +24,7 @@
   <string name="cat_topappbar_scrolling_transparent_title" translatable="false">Scrolling Demo (transparent status bar)</string>
   <string name="cat_topappbar_collapsing_medium_title" translatable="false">Collapsing Demo (Medium)</string>
   <string name="cat_topappbar_collapsing_large_title" translatable="false">Collapsing Demo (Large)</string>
+  <string name="cat_topappbar_collapsing_large_middle_ellipsize_title" translatable="false">Collapsing Demo (Large Middle Ellipsize)</string>
   <string name="cat_topappbar_toolbar_title" translatable="false">Toolbar Demo</string>
   <string name="cat_topappbar_collapsing_multiline_title" translatable="false">Collapsing Demo (Multiline title)</string>
   <string name="cat_topappbar_action_bar_title" translatable="false">Action Bar Demo</string>

lib/java/com/google/android/material/appbar/CollapsingToolbarLayout.java

@@ -261,6 +261,12 @@ public CollapsingToolbarLayout(@NonNull Context context, @Nullable AttributeSet
           a.getResourceId(R.styleable.CollapsingToolbarLayout_collapsedTitleTextAppearance, 0));
     }
 
+    // Now overlay any custom text Ellipsize
+    if (a.hasValue(R.styleable.CollapsingToolbarLayout_titleTextEllipsize)) {
+      collapsingTextHelper.setTitleTextEllipsize(
+          a.getInt(R.styleable.CollapsingToolbarLayout_titleTextEllipsize, 2));
+    }
+
     if (a.hasValue(R.styleable.CollapsingToolbarLayout_expandedTitleTextColor)) {
       collapsingTextHelper.setExpandedTextColor(
           MaterialResources.getColorStateList(

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

@@ -152,6 +152,13 @@
     <!-- The text appearance of the CollapsingToolbarLayouts title when it is fully
          'collapsed' -->
     <attr name="collapsedTitleTextAppearance" format="reference"/>
+    <!-- The text ellipsize of the collapsedToolbarLayout title -->
+    <attr name="titleTextEllipsize" format="enum">
+      <enum name="start" value="0" />
+      <enum name="middle" value="1" />
+      <enum name="end" value="2" />
+      <enum name="marquee" value="3" />
+    </attr>
     <!-- The text color of the CollapsingToolbarLayout's title when it is fully
          'expanded' -->
     <attr name="expandedTitleTextColor" format="color|reference"/>

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

@@ -126,6 +126,8 @@ public final class CollapsingTextHelper {
   private CancelableFontCallback expandedFontCallback;
   private CancelableFontCallback collapsedFontCallback;
 
+  private TruncateAt titleTextEllipsize = TruncateAt.END;
+
   @Nullable private CharSequence text;
   @Nullable private CharSequence textToDraw;
   private boolean isRtl;
@@ -447,6 +449,26 @@ public void apply(Typeface font) {
     recalculate();
   }
 
+  public void setTitleTextEllipsize(int ellipsize) {
+    // Convert to supported TextUtils.TruncateAt values
+    switch (ellipsize) {
+      case 0:
+        titleTextEllipsize = TextUtils.TruncateAt.START;
+        break;
+      case 1:
+        titleTextEllipsize = TextUtils.TruncateAt.MIDDLE;
+        break;
+      case 2:
+        titleTextEllipsize = TextUtils.TruncateAt.END;
+        break;
+      case 3:
+        titleTextEllipsize = TruncateAt.MARQUEE;
+      default: // fall out
+        titleTextEllipsize = TextUtils.TruncateAt.END;
+        break;
+    }
+  }
+
   public void setCollapsedTypeface(Typeface typeface) {
     if (setCollapsedTypefaceInternal(typeface)) {
       recalculate();
@@ -710,7 +732,7 @@ private void calculateBaseOffsets(boolean forceRecalculate) {
     calculateUsingTextSize(/* fraction= */ 1, forceRecalculate);
     if (textToDraw != null && textLayout != null) {
       textToDrawCollapsed =
-          TextUtils.ellipsize(textToDraw, textPaint, textLayout.getWidth(), TruncateAt.END);
+          TextUtils.ellipsize(textToDraw, textPaint, textLayout.getWidth(), titleTextEllipsize);
     }
     if (textToDrawCollapsed != null) {
       collapsedTextWidth = measureTextWidth(textPaint, textToDrawCollapsed);
@@ -1061,7 +1083,7 @@ private StaticLayout createStaticLayout(int maxLines, float availableWidth, bool
       Alignment textAlignment = maxLines == 1 ? ALIGN_NORMAL : getMultilineTextLayoutAlignment();
       textLayout =
           StaticLayoutBuilderCompat.obtain(text, textPaint, (int) availableWidth)
-              .setEllipsize(TruncateAt.END)
+              .setEllipsize(titleTextEllipsize)
               .setIsRtl(isRtl)
               .setAlignment(textAlignment)
               .setIncludePad(false)