Adds urlspan to support link semantics in Android (#162419)

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fixes https://github.com/flutter/flutter/issues/102535

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engine/src/flutter/shell/platform/android/io/flutter/view/AccessibilityBridge.java

@@ -24,6 +24,7 @@ import android.text.SpannableString;
 import android.text.TextUtils;
 import android.text.style.LocaleSpan;
 import android.text.style.TtsSpan;
+import android.text.style.URLSpan;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.WindowInsets;
@@ -748,7 +749,7 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
       result.addAction(AccessibilityNodeInfo.ACTION_SET_TEXT);
     }
 
-    if (semanticsNode.hasFlag(Flag.IS_BUTTON) || semanticsNode.hasFlag(Flag.IS_LINK)) {
+    if (semanticsNode.hasFlag(Flag.IS_BUTTON)) {
       result.setClassName("android.widget.Button");
     }
     if (semanticsNode.hasFlag(Flag.IS_IMAGE)) {
@@ -2262,6 +2263,7 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
   private enum StringAttributeType {
     SPELLOUT,
     LOCALE,
+    URL
   }
 
   private static class StringAttribute {
@@ -2276,6 +2278,10 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
     String locale;
   }
 
+  private static class UrlStringAttribute extends StringAttribute {
+    String url;
+  }
+
   /**
    * Flutter {@code SemanticsNode} represented in Java/Android.
    *
@@ -2329,6 +2335,9 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
     // API level >= 28; otherwise, this is attached to the end of content description.
     @Nullable private String tooltip;
 
+    // The Url the widget's points to.
+    @Nullable private String linkUrl;
+
     // The id of the sibling node that is before this node in traversal
     // order.
     //
@@ -2540,6 +2549,9 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
       stringIndex = buffer.getInt();
       tooltip = stringIndex == -1 ? null : strings[stringIndex];
 
+      stringIndex = buffer.getInt();
+      linkUrl = stringIndex == -1 ? null : strings[stringIndex];
+
       textDirection = TextDirection.fromInt(buffer.getInt());
 
       left = buffer.getFloat();
@@ -2832,7 +2844,21 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
     }
 
     private CharSequence getLabel() {
-      return createSpannableString(label, labelAttributes);
+      List<StringAttribute> attributes = labelAttributes;
+      if (linkUrl != null && linkUrl.length() > 0) {
+        if (attributes == null) {
+          attributes = new ArrayList<StringAttribute>();
+        } else {
+          attributes = new ArrayList<StringAttribute>(attributes);
+        }
+        UrlStringAttribute uriStringAttribute = new UrlStringAttribute();
+        uriStringAttribute.start = 0;
+        uriStringAttribute.end = label.length();
+        uriStringAttribute.url = linkUrl;
+        uriStringAttribute.type = StringAttributeType.URL;
+        attributes.add(uriStringAttribute);
+      }
+      return createSpannableString(label, attributes);
     }
 
     private CharSequence getHint() {
@@ -2891,6 +2917,13 @@ public class AccessibilityBridge extends AccessibilityNodeProvider {
                 spannableString.setSpan(localeSpan, attribute.start, attribute.end, 0);
                 break;
               }
+            case URL:
+              {
+                UrlStringAttribute uriAttribute = (UrlStringAttribute) attribute;
+                final URLSpan urlSpan = new URLSpan(uriAttribute.url);
+                spannableString.setSpan(urlSpan, attribute.start, attribute.end, 0);
+                break;
+              }
           }
         }
       }

engine/src/flutter/shell/platform/android/platform_view_android_delegate/platform_view_android_delegate.cc

@@ -44,7 +44,7 @@ PlatformViewAndroidDelegate::PlatformViewAndroidDelegate(
 void PlatformViewAndroidDelegate::UpdateSemantics(
     const flutter::SemanticsNodeUpdates& update,
     const flutter::CustomAccessibilityActionUpdates& actions) {
-  constexpr size_t kBytesPerNode = 48 * sizeof(int32_t);
+  constexpr size_t kBytesPerNode = 49 * sizeof(int32_t);
   constexpr size_t kBytesPerChild = sizeof(int32_t);
   constexpr size_t kBytesPerCustomAction = sizeof(int32_t);
   constexpr size_t kBytesPerAction = 4 * sizeof(int32_t);
@@ -165,6 +165,13 @@ void PlatformViewAndroidDelegate::UpdateSemantics(
         strings.push_back(node.tooltip);
       }
 
+      if (node.linkUrl.empty()) {
+        buffer_int32[position++] = -1;
+      } else {
+        buffer_int32[position++] = strings.size();
+        strings.push_back(node.linkUrl);
+      }
+
       buffer_int32[position++] = node.textDirection;
       buffer_float32[position++] = node.rect.left();
       buffer_float32[position++] = node.rect.top();

engine/src/flutter/shell/platform/android/platform_view_android_delegate/platform_view_android_delegate_unittests.cc

@@ -23,7 +23,7 @@ TEST(PlatformViewShell, UpdateSemanticsDoesFlutterViewUpdateSemantics) {
   node0.tooltip = "tooltip";
   update.insert(std::make_pair(0, node0));
 
-  std::vector<uint8_t> expected_buffer(192);
+  std::vector<uint8_t> expected_buffer(196);
   std::vector<std::vector<uint8_t>> expected_string_attribute_args(0);
   size_t position = 0;
   int32_t* buffer_int32 = reinterpret_cast<int32_t*>(&expected_buffer[0]);
@@ -57,6 +57,71 @@ TEST(PlatformViewShell, UpdateSemanticsDoesFlutterViewUpdateSemantics) {
   buffer_int32[position++] = -1;  // node0.hintAttributes
   buffer_int32[position++] = expected_strings.size();  // node0.tooltip
   expected_strings.push_back(node0.tooltip);
+  buffer_int32[position++] = -1;  // node0.linkUrl
+  buffer_int32[position++] = node0.textDirection;
+  buffer_float32[position++] = node0.rect.left();
+  buffer_float32[position++] = node0.rect.top();
+  buffer_float32[position++] = node0.rect.right();
+  buffer_float32[position++] = node0.rect.bottom();
+  node0.transform.getColMajor(&buffer_float32[position]);
+  position += 16;
+  buffer_int32[position++] = 0;  // node0.childrenInTraversalOrder.size();
+  buffer_int32[position++] = 0;  // node0.customAccessibilityActions.size();
+  EXPECT_CALL(*jni_mock,
+              FlutterViewUpdateSemantics(expected_buffer, expected_strings,
+                                         expected_string_attribute_args));
+  // Creates empty custom actions.
+  flutter::CustomAccessibilityActionUpdates actions;
+  delegate->UpdateSemantics(update, actions);
+}
+
+TEST(PlatformViewShell, UpdateSemanticsDoesUpdatelinkUrl) {
+  auto jni_mock = std::make_shared<JNIMock>();
+  auto delegate = std::make_unique<PlatformViewAndroidDelegate>(jni_mock);
+
+  flutter::SemanticsNodeUpdates update;
+  flutter::SemanticsNode node0;
+  node0.id = 0;
+  node0.identifier = "identifier";
+  node0.label = "label";
+  node0.linkUrl = "url";
+  update.insert(std::make_pair(0, node0));
+
+  std::vector<uint8_t> expected_buffer(196);
+  std::vector<std::vector<uint8_t>> expected_string_attribute_args(0);
+  size_t position = 0;
+  int32_t* buffer_int32 = reinterpret_cast<int32_t*>(&expected_buffer[0]);
+  float* buffer_float32 = reinterpret_cast<float*>(&expected_buffer[0]);
+  std::vector<std::string> expected_strings;
+  buffer_int32[position++] = node0.id;
+  buffer_int32[position++] = node0.flags;
+  buffer_int32[position++] = node0.actions;
+  buffer_int32[position++] = node0.maxValueLength;
+  buffer_int32[position++] = node0.currentValueLength;
+  buffer_int32[position++] = node0.textSelectionBase;
+  buffer_int32[position++] = node0.textSelectionExtent;
+  buffer_int32[position++] = node0.platformViewId;
+  buffer_int32[position++] = node0.scrollChildren;
+  buffer_int32[position++] = node0.scrollIndex;
+  buffer_float32[position++] = static_cast<float>(node0.scrollPosition);
+  buffer_float32[position++] = static_cast<float>(node0.scrollExtentMax);
+  buffer_float32[position++] = static_cast<float>(node0.scrollExtentMin);
+  buffer_int32[position++] = expected_strings.size();  // node0.identifier
+  expected_strings.push_back(node0.identifier);
+  buffer_int32[position++] = expected_strings.size();  // node0.label
+  expected_strings.push_back(node0.label);
+  buffer_int32[position++] = -1;  // node0.labelAttributes
+  buffer_int32[position++] = -1;  // node0.value
+  buffer_int32[position++] = -1;  // node0.valueAttributes
+  buffer_int32[position++] = -1;  // node0.increasedValue
+  buffer_int32[position++] = -1;  // node0.increasedValueAttributes
+  buffer_int32[position++] = -1;  // node0.decreasedValue
+  buffer_int32[position++] = -1;  // node0.decreasedValueAttributes
+  buffer_int32[position++] = -1;  // node0.hint
+  buffer_int32[position++] = -1;  // node0.hintAttributes
+  buffer_int32[position++] = -1;  // node0.tooltip
+  buffer_int32[position++] = expected_strings.size();  // node0.tooltip
+  expected_strings.push_back(node0.linkUrl);
   buffer_int32[position++] = node0.textDirection;
   buffer_float32[position++] = node0.rect.left();
   buffer_float32[position++] = node0.rect.top();
@@ -100,7 +165,7 @@ TEST(PlatformViewShell,
   node0.hintAttributes.push_back(locale_attribute);
   update.insert(std::make_pair(0, node0));
 
-  std::vector<uint8_t> expected_buffer(224);
+  std::vector<uint8_t> expected_buffer(228);
   std::vector<std::vector<uint8_t>> expected_string_attribute_args;
   size_t position = 0;
   int32_t* buffer_int32 = reinterpret_cast<int32_t*>(&expected_buffer[0]);
@@ -145,6 +210,7 @@ TEST(PlatformViewShell,
   expected_string_attribute_args.push_back(
       {locale_attribute->locale.begin(), locale_attribute->locale.end()});
   buffer_int32[position++] = -1;  // node0.tooltip
+  buffer_int32[position++] = -1;  // node0.linkUrl
   buffer_int32[position++] = node0.textDirection;
   buffer_float32[position++] = node0.rect.left();
   buffer_float32[position++] = node0.rect.top();

engine/src/flutter/shell/platform/android/test/io/flutter/view/AccessibilityBridgeTest.java

@@ -37,6 +37,7 @@ import android.text.SpannableString;
 import android.text.SpannedString;
 import android.text.style.LocaleSpan;
 import android.text.style.TtsSpan;
+import android.text.style.URLSpan;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewParent;
@@ -193,6 +194,26 @@ public class AccessibilityBridgeTest {
     assertEquals(nodeInfo.getText(), null);
   }
 
+  @Test
+  public void itCreatesURLSpanForlinkURL() {
+    AccessibilityBridge accessibilityBridge = setUpBridge();
+
+    TestSemanticsNode testSemanticsNode = new TestSemanticsNode();
+    testSemanticsNode.label = "Hello";
+    testSemanticsNode.linkUrl = "https://flutter.dev";
+    testSemanticsNode.addFlag(AccessibilityBridge.Flag.IS_LINK);
+    TestSemanticsUpdate testSemanticsUpdate = testSemanticsNode.toUpdate();
+
+    testSemanticsUpdate.sendUpdateToBridge(accessibilityBridge);
+    AccessibilityNodeInfo nodeInfo = accessibilityBridge.createAccessibilityNodeInfo(0);
+    SpannableString actual = (SpannableString) nodeInfo.getContentDescription();
+    assertEquals(actual.toString(), "Hello");
+    Object[] objectSpans = actual.getSpans(0, actual.length(), Object.class);
+    assertEquals(objectSpans.length, 1);
+    URLSpan span = (URLSpan) objectSpans[0];
+    assertEquals(span.getURL(), "https://flutter.dev");
+  }
+
   @Test
   public void itUnfocusesPlatformViewWhenPlatformViewGoesAway() {
     AccessibilityViewEmbedder mockViewEmbedder = mock(AccessibilityViewEmbedder.class);
@@ -2311,6 +2332,7 @@ public class AccessibilityBridgeTest {
     String hint = null;
     List<TestStringAttribute> hintAttributes;
     String tooltip = null;
+    String linkUrl = null;
     int textDirection = 0;
     float left = 0.0f;
     float top = 0.0f;
@@ -2374,6 +2396,12 @@ public class AccessibilityBridgeTest {
         strings.add(tooltip);
         bytes.putInt(strings.size() - 1);
       }
+      if (linkUrl == null) {
+        bytes.putInt(-1);
+      } else {
+        strings.add(linkUrl);
+        bytes.putInt(strings.size() - 1);
+      }
       bytes.putInt(textDirection);
       bytes.putFloat(left);
       bytes.putFloat(top);