Implemented value changing control patterns in IAccessibleEx, allowing for...

Implemented value changing control patterns in IAccessibleEx, allowing for manipulation of basic fields with values

R=nektar@chromium.org,dmazzoni@chromium.org

Bug: 852965
Change-Id: I080188507ac4dd0bd7548bec89a9ec069e581b85
Reviewed-on: https://chromium-review.googlesource.com/1101837
Commit-Queue: Nektarios Paisios <nektar@chromium.org>
Reviewed-by: Nektarios Paisios <nektar@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569648}

ui/accessibility/platform/ax_platform_node_win.cc

@@ -169,6 +169,10 @@ base::LazyInstance<AXPlatformNodeWinSet>::Leaky g_alert_targets =
 base::LazyInstance<base::ObserverList<IAccessible2UsageObserver>>::Leaky
     g_iaccessible2_usage_observer_list = LAZY_INSTANCE_INITIALIZER;
 
+// Sets the multiplier by which large changes to a RangeValueProvider are
+// greater than small changes
+constexpr int kLargeChangeScaleFactor = 10;
+
 }  // namespace
 
 // There is no easy way to decouple |kScreenReader| and |kHTML| accessibility
@@ -1419,6 +1423,108 @@ STDMETHODIMP AXPlatformNodeWin::ScrollIntoView() {
   return E_FAIL;
 }
 
+//
+// IValueProvider implementation.
+//
+
+STDMETHODIMP AXPlatformNodeWin::SetValue(LPCWSTR value) {
+  if (!value)
+    return E_INVALIDARG;
+
+  AXActionData data;
+  data.action = ax::mojom::Action::kSetValue;
+  data.value = base::string16(value);
+  if (delegate_->AccessibilityPerformAction(data))
+    return S_OK;
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_IsReadOnly(BOOL* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  int restriction;
+  if (GetIntAttribute(ax::mojom::IntAttribute::kRestriction, &restriction)) {
+    *result = static_cast<ax::mojom::Restriction>(restriction) ==
+              ax::mojom::Restriction::kReadOnly;
+    return S_OK;
+  }
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_Value(BSTR* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  if (GetStringAttributeAsBstr(ax::mojom::StringAttribute::kValue, result))
+    return S_OK;
+  return E_FAIL;
+}
+
+//
+// IRangeValueProvider implementation.
+//
+
+STDMETHODIMP AXPlatformNodeWin::SetValue(double value) {
+  AXActionData data;
+  data.action = ax::mojom::Action::kSetValue;
+  data.value = base::NumberToString16(value);
+  if (delegate_->AccessibilityPerformAction(data))
+    return S_OK;
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_LargeChange(double* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  float attribute;
+  if (GetFloatAttribute(ax::mojom::FloatAttribute::kStepValueForRange,
+                        &attribute)) {
+    *result = attribute * kLargeChangeScaleFactor;
+    return S_OK;
+  }
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_Maximum(double* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  float attribute;
+  if (GetFloatAttribute(ax::mojom::FloatAttribute::kMaxValueForRange,
+                        &attribute)) {
+    *result = attribute;
+    return S_OK;
+  }
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_Minimum(double* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  float attribute;
+  if (GetFloatAttribute(ax::mojom::FloatAttribute::kMinValueForRange,
+                        &attribute)) {
+    *result = attribute;
+    return S_OK;
+  }
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_SmallChange(double* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  float attribute;
+  if (GetFloatAttribute(ax::mojom::FloatAttribute::kStepValueForRange,
+                        &attribute)) {
+    *result = attribute;
+    return S_OK;
+  }
+  return E_FAIL;
+}
+
+STDMETHODIMP AXPlatformNodeWin::get_Value(double* result) {
+  COM_OBJECT_VALIDATE_1_ARG(result);
+  float attribute;
+  if (GetFloatAttribute(ax::mojom::FloatAttribute::kValueForRange,
+                        &attribute)) {
+    *result = attribute;
+    return S_OK;
+  }
+  return E_FAIL;
+}
+
 // IAccessibleEx methods not implemented.
 STDMETHODIMP AXPlatformNodeWin::GetRuntimeId(SAFEARRAY** runtime_id) {
   WIN_ACCESSIBILITY_API_HISTOGRAM(UMA_API_GET_RUNTIME_ID);
@@ -2569,19 +2675,25 @@ STDMETHODIMP AXPlatformNodeWin::GetPatternProvider(PATTERNID pattern_id,
     case UIA_GridPatternId:
     case UIA_GridItemPatternId:
     case UIA_MultipleViewPatternId:
+      break;
+
     case UIA_RangeValuePatternId:
+      *result = static_cast<IRawElementProviderSimple*>(this);
+      AddRef();
+      break;
+
     case UIA_ScrollPatternId:
-      *result = nullptr;
       break;
+
     case UIA_ScrollItemPatternId:
       *result = static_cast<IRawElementProviderSimple*>(this);
       AddRef();
       break;
+
     case UIA_SynchronizedInputPatternId:
     case UIA_TablePatternId:
     case UIA_TableItemPatternId:
     case UIA_TransformPatternId:
-      *result = nullptr;
       break;
 
     // TODO(suproteem): Add checks for control role.
@@ -2589,7 +2701,13 @@ STDMETHODIMP AXPlatformNodeWin::GetPatternProvider(PATTERNID pattern_id,
     case UIA_SelectionItemPatternId:
     case UIA_SelectionPatternId:
     case UIA_TogglePatternId:
+      break;
+
     case UIA_ValuePatternId:
+      *result = static_cast<IRawElementProviderSimple*>(this);
+      AddRef();
+      break;
+
     case UIA_WindowPatternId:
 
     // Overlap with MSAA, not supported.
@@ -2609,7 +2727,6 @@ STDMETHODIMP AXPlatformNodeWin::GetPatternProvider(PATTERNID pattern_id,
     case UIA_TextPattern2Id:
     case UIA_TransformPattern2Id:
     case UIA_VirtualizedItemPatternId:
-      *result = nullptr;
       break;
   }
   return S_OK;

ui/accessibility/platform/ax_platform_node_win.h

@@ -241,9 +241,11 @@ class AX_EXPORT __declspec(uuid("26f5641a-246d-457b-a96d-07f3fae6acf2"))
                         public IAccessibleTable,
                         public IAccessibleTable2,
                         public IAccessibleTableCell,
+                        public IRangeValueProvider,
                         public IRawElementProviderSimple,
                         public IScrollItemProvider,
                         public IServiceProvider,
+                        public IValueProvider,
                         public AXPlatformNodeBase {
  public:
   BEGIN_COM_MAP(AXPlatformNodeWin)
@@ -257,8 +259,10 @@ class AX_EXPORT __declspec(uuid("26f5641a-246d-457b-a96d-07f3fae6acf2"))
     COM_INTERFACE_ENTRY(IAccessibleTable)
     COM_INTERFACE_ENTRY(IAccessibleTable2)
     COM_INTERFACE_ENTRY(IAccessibleTableCell)
+    COM_INTERFACE_ENTRY(IRangeValueProvider)
     COM_INTERFACE_ENTRY(IRawElementProviderSimple)
     COM_INTERFACE_ENTRY(IScrollItemProvider)
+    COM_INTERFACE_ENTRY(IValueProvider)
     COM_INTERFACE_ENTRY(IServiceProvider)
   END_COM_MAP()
 
@@ -426,6 +430,32 @@ class AX_EXPORT __declspec(uuid("26f5641a-246d-457b-a96d-07f3fae6acf2"))
 
   STDMETHODIMP ScrollIntoView() override;
 
+  //
+  // IValueProvider methods.
+  //
+
+  STDMETHODIMP SetValue(LPCWSTR val) override;
+
+  STDMETHODIMP get_IsReadOnly(BOOL* result) override;
+
+  STDMETHODIMP get_Value(BSTR* result) override;
+
+  //
+  // IRangeValueProvider methods.
+  //
+
+  STDMETHODIMP SetValue(double val) override;
+
+  STDMETHODIMP get_LargeChange(double* result) override;
+
+  STDMETHODIMP get_Maximum(double* result) override;
+
+  STDMETHODIMP get_Minimum(double* result) override;
+
+  STDMETHODIMP get_SmallChange(double* result) override;
+
+  STDMETHODIMP get_Value(double* result) override;
+
   // IAccessibleEx methods not implemented.
   STDMETHODIMP GetRuntimeId(SAFEARRAY** runtime_id) override;
 

ui/base/win/accessibility_misc_utils.cc

@@ -36,24 +36,6 @@ bool UIATextProvider::CreateTextProvider(const string16& value,
   return false;
 }
 
-STDMETHODIMP UIATextProvider::get_IsReadOnly(BOOL* read_only) {
-  *read_only = !editable_;
-  return S_OK;
-}
-
-//
-// IValueProvider methods.
-//
-
-STDMETHODIMP UIATextProvider::SetValue(const wchar_t* val) {
-  return E_NOTIMPL;
-}
-
-STDMETHODIMP UIATextProvider::get_Value(BSTR* value) {
-  *value = SysAllocString(value_.c_str());
-  return S_OK;
-}
-
 //
 // ITextProvider methods.
 //

ui/base/win/accessibility_misc_utils.h

@@ -18,12 +18,10 @@ namespace win {
   // UIA Text provider implementation for edit controls.
 class UI_BASE_EXPORT UIATextProvider
     : public CComObjectRootEx<CComMultiThreadModel>,
-      public IValueProvider,
       public ITextProvider {
  public:
   BEGIN_COM_MAP(UIATextProvider)
     COM_INTERFACE_ENTRY2(IUnknown, ITextProvider)
-    COM_INTERFACE_ENTRY(IValueProvider)
     COM_INTERFACE_ENTRY(ITextProvider)
   END_COM_MAP()
 
@@ -42,18 +40,6 @@ class UI_BASE_EXPORT UIATextProvider
 
   void set_value(const string16& value) { value_ = value; }
 
-  //
-  // IValueProvider methods.
-  //
-  STDMETHOD(get_IsReadOnly)(BOOL* read_only) override;
-
-  //
-  // IValueProvider methods.
-  //
-  STDMETHOD(SetValue)(const wchar_t* val) override;
-
-  STDMETHOD(get_Value)(BSTR* value) override;
-
   //
   // ITextProvider methods.
   //