Improve accessibility code for countries list.

Telegram/SourceFiles/boxes/language_box.cpp

@@ -7,56 +7,55 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #include "boxes/language_box.h"
 
-#include "data/data_peer_values.h"
-#include "lang/lang_keys.h"
-#include "base/screen_reader_state.h"
-#include "ui/accessible/ui_accessible_item.h"
-#include "ui/boxes/choose_language_box.h"
-#include "ui/widgets/checkbox.h"
-#include "ui/widgets/buttons.h"
-#include "ui/widgets/labels.h"
-#include "ui/widgets/multi_select.h"
-#include "ui/widgets/scroll_area.h"
-#include "ui/widgets/dropdown_menu.h"
-#include "ui/widgets/box_content_divider.h"
-#include "ui/text/text_entity.h"
-#include "ui/wrap/vertical_layout.h"
-#include "ui/wrap/slide_wrap.h"
-#include "ui/effects/ripple_animation.h"
-#include "ui/toast/toast.h"
-#include "ui/text/text_options.h"
-#include "ui/painter.h"
-#include "ui/vertical_list.h"
-#include "ui/ui_utility.h"
-#include "storage/localstorage.h"
+#include "base/platform/base_platform_info.h"
 #include "boxes/abstract_box.h"
 #include "boxes/premium_preview_box.h"
 #include "boxes/translate_box.h"
-#include "ui/boxes/confirm_box.h"
-#include "main/main_session.h"
-#include "mainwidget.h"
-#include "mainwindow.h"
 #include "core/application.h"
-#include "base/platform/base_platform_info.h"
-#include "lang/lang_instance.h"
+#include "data/data_peer_values.h"
 #include "lang/lang_cloud_manager.h"
+#include "lang/lang_instance.h"
+#include "lang/lang_keys.h"
+#include "main/main_session.h"
 #include "platform/platform_translate_provider.h"
 #include "settings/settings_common.h"
 #include "spellcheck/spellcheck_types.h"
+#include "storage/localstorage.h"
+#include "ui/accessible/ui_accessible_item.h"
+#include "ui/boxes/choose_language_box.h"
+#include "ui/boxes/confirm_box.h"
+#include "ui/effects/ripple_animation.h"
+#include "ui/text/text_entity.h"
+#include "ui/text/text_options.h"
+#include "ui/toast/toast.h"
+#include "ui/widgets/box_content_divider.h"
+#include "ui/widgets/buttons.h"
+#include "ui/widgets/checkbox.h"
+#include "ui/widgets/dropdown_menu.h"
+#include "ui/widgets/labels.h"
+#include "ui/widgets/multi_select.h"
+#include "ui/widgets/scroll_area.h"
+#include "ui/wrap/slide_wrap.h"
+#include "ui/wrap/vertical_layout.h"
+#include "ui/painter.h"
+#include "ui/screen_reader_mode.h"
+#include "ui/ui_utility.h"
+#include "ui/vertical_list.h"
 #include "window/window_controller.h"
 #include "window/window_session_controller.h"
-#include "styles/style_layers.h"
+#include "mainwidget.h"
+#include "mainwindow.h"
+
 #include "styles/style_boxes.h"
-#include "styles/style_info.h"
-#include "styles/style_passport.h"
 #include "styles/style_chat_helpers.h"
+#include "styles/style_info.h"
+#include "styles/style_layers.h"
 #include "styles/style_menu_icons.h"
+#include "styles/style_passport.h"
 #include "styles/style_settings.h"
 
-#include <unordered_map>
-
-#include <QtGui/QGuiApplication>
 #include <QtGui/QClipboard>
+#include <QtGui/QGuiApplication>
 
 namespace {
 
@@ -89,80 +88,17 @@ public:
 
 	static int DefaultRowHeight();
 
-	QAccessible::Role accessibilityRole() override {
-		return QAccessible::List;
-	}
-
-	QAccessible::Role accessibilityChildRole() const override {
-		return QAccessible::RadioButton;
-	}
-
-	QAccessible::State accessibilityChildState(int index) const override {
-		QAccessible::State state;
-		if (base::ScreenReaderState::Instance()->active()) {
-			state.focusable = true;
-		}
-		state.checkable = true;
-		state.checked = (index == chosenIndex());
-		if (index == selected()) {
-			state.active = true;
-			if (hasFocus()) {
-				state.focused = true;
-			}
-		}
-		return state;
-	}
-
-	int accessibilityChildCount() const override {
-		return count();
-	}
-
-	QString accessibilityChildName(int index) const override {
-		if (index < 0 || index >= count()) {
-			return {};
-		}
-		const auto &row = rowByIndex(index);
-		// Announce native name followed by English name.
-		return row.data.nativeName + u", "_q + row.data.name;
-	}
-
-	QRect accessibilityChildRect(int index) const override {
-		if (index < 0 || index >= count()) {
-			return QRect();
-		}
-		const auto &row = rowByIndex(index);
-		return QRect(0, row.top, width(), row.height);
-	}
-
-	int accessibilityChildColumnCount(int row) const override {
-		return 2;
-	}
-
-	QAccessible::Role accessibilityChildSubItemRole() const override {
-		return QAccessible::Cell;
-	}
-
-	QString accessibilityChildSubItemName(int row, int column) const override {
-		if (column == 0) {
-			return tr::lng_sr_languages_column_native(tr::now);
-		} else if (column == 1) {
-			return tr::lng_sr_languages_column_name(tr::now);
-		}
-		return {};
-	}
-
-	QString accessibilityChildSubItemValue(int row, int column) const override {
-		if (row < 0 || row >= count()) {
-			return {};
-		}
-		const auto &data = rowByIndex(row).data;
-		if (column == 0) {
-			return data.nativeName;
-		} else if (column == 1) {
-			return data.name;
-		}
-		return {};
-	}
+	QAccessible::Role accessibilityRole() override;
+	Qt::FocusPolicy accessibilityFocusPolicy() override;
+	QAccessible::Role accessibilityChildRole() const override;
+	QAccessible::State accessibilityChildState(int index) const override;
+	int accessibilityChildCount() const override;
+	QString accessibilityChildName(int index) const override;
+	QRect accessibilityChildRect(int index) const override;
+	int accessibilityChildColumnCount(int row) const override;
+	QAccessible::Role accessibilityChildSubItemRole() const override;
+	QString accessibilityChildSubItemName(int row, int column) const override;
+	QString accessibilityChildSubItemValue(int row, int column) const override;
 
 protected:
 	int resizeGetHeight(int newWidth) override;
@@ -237,6 +173,13 @@ private:
 	void repaintChecked(not_null<const Row*> row);
 	void activateByIndex(int index);
 
+	enum class Announce {
+		No,
+		OnChange,
+		Always,
+	};
+	void setSelected(int index, Announce announce);
+
 	void showMenu(int index);
 	void setForceRippled(not_null<Row*> row, bool rippled);
 	bool canShare(not_null<const Row*> row) const;
@@ -266,6 +209,26 @@ private:
 
 };
 
+[[nodiscard]] bool ForwardListNavigation(
+		not_null<QKeyEvent*> e,
+		not_null<Rows*> rows,
+		int pageHeight) {
+	const auto key = e->key();
+	if (key == Qt::Key_Down) {
+		rows->selectSkip(1);
+	} else if (key == Qt::Key_Up) {
+		rows->selectSkip(-1);
+	} else if (key == Qt::Key_PageDown || key == Qt::Key_PageUp) {
+		const auto perPage = std::max(
+			pageHeight / Rows::DefaultRowHeight(),
+			1);
+		rows->selectSkip((key == Qt::Key_PageDown) ? perPage : -perPage);
+	} else {
+		return false;
+	}
+	return true;
+}
+
 class Content : public Ui::RpWidget {
 public:
 	Content(
@@ -373,53 +336,34 @@ Rows::Rows(
 	update();
 
 	setAccessibleName(tr::lng_languages(tr::now));
-
-	base::ScreenReaderState::Instance()->activeValue(
-	) | rpl::on_next([=](bool active) {
-		setFocusPolicy(active ? Qt::TabFocus : Qt::NoFocus);
-	}, lifetime());
 }
 
 void Rows::focusInEvent(QFocusEvent *e) {
-	// Select first item or chosen item when focus enters.
 	if (selected() < 0 && count() > 0) {
 		const auto chosen = chosenIndex();
-		setSelected(chosen >= 0 ? chosen : 0);
+		setSelected(chosen >= 0 ? chosen : 0, Announce::No);
 	}
-
 	RpWidget::focusInEvent(e);
-
-	if (base::ScreenReaderState::Instance()->active()) {
-		const auto index = selected();
-		if (index >= 0) {
-			InvokeQueued(this, [=] {
-				if (selected() != index || !hasFocus()) {
-					return;
-				}
+	const auto index = selected();
+	if (index >= 0) {
+		InvokeQueued(this, [=] {
+			if (selected() == index && hasFocus()) {
 				accessibilityChildFocused(index);
-			});
-		}
+			}
+		});
 	}
 }
 
 void Rows::keyPressEvent(QKeyEvent *e) {
+	const auto pageHeight = window() ? window()->height() : height();
+	if (ForwardListNavigation(e, this, pageHeight)) {
+		return;
+	}
 	const auto key = e->key();
-	if (key == Qt::Key_Down) {
-		selectSkip(1);
-	} else if (key == Qt::Key_Up) {
-		selectSkip(-1);
-	} else if (key == Qt::Key_PageDown || key == Qt::Key_PageUp) {
-		const auto visibleHeight = visibleRegion().boundingRect().height();
-		const auto rowsPerPage = std::max(visibleHeight / DefaultRowHeight(), 1);
-		selectSkip(key == Qt::Key_PageDown ? rowsPerPage : -rowsPerPage);
-	} else if (key == Qt::Key_Home) {
-		if (count() > 0) {
-			setSelected(0);
-		}
-	} else if (key == Qt::Key_End) {
-		if (count() > 0) {
-			setSelected(count() - 1);
-		}
+	if (key == Qt::Key_Home && count() > 0) {
+		setSelected(0, Announce::Always);
+	} else if (key == Qt::Key_End && count() > 0) {
+		setSelected(count() - 1, Announce::Always);
 	} else if (!e->isAutoRepeat()
 		&& (key == Qt::Key_Space
 			|| key == Qt::Key_Return
@@ -697,10 +641,8 @@ void Rows::setForceRippled(not_null<Row*> row, bool rippled) {
 void Rows::activateByIndex(int index) {
 	_chosen = rowByIndex(index).data.id;
 	_activations.fire_copy(rowByIndex(index).data);
-	if (base::ScreenReaderState::Instance()->active()) {
-		accessibilityChildStateChanged(index, { .checked = true });
-		accessibilityChildNameChanged(index);
-	}
+	accessibilityChildStateChanged(index, { .checked = true });
+	accessibilityChildNameChanged(index);
 }
 
 void Rows::leaveEventHook(QEvent *e) {
@@ -795,21 +737,20 @@ void Rows::activateSelected() {
 void Rows::selectSkip(int dir) {
 	const auto limit = count();
 	auto now = selected();
-	// If no keyboard selection, start from the checked item.
 	if (now < 0) {
 		now = chosenIndex();
 	}
 	if (now >= 0) {
 		const auto changed = now + dir;
 		if (changed < 0) {
-			setSelected(0);
+			setSelected(0, Announce::Always);
 		} else if (changed >= limit) {
-			setSelected(limit - 1);
+			setSelected(limit - 1, Announce::Always);
 		} else {
-			setSelected(changed);
+			setSelected(changed, Announce::Always);
 		}
 	} else if (dir > 0) {
-		setSelected(0);
+		setSelected(0, Announce::Always);
 	}
 }
 
@@ -823,27 +764,35 @@ void Rows::changeChosen(const QString &chosen) {
 	for (const auto &row : _rows) {
 		row.check->setChecked(row.data.id == chosen, anim::type::normal);
 	}
-	if (base::ScreenReaderState::Instance()->active()) {
-		const auto newIndex = chosenIndex();
-		if (newIndex != oldIndex && newIndex >= 0) {
-			accessibilityChildStateChanged(newIndex, { .checked = true });
-			accessibilityChildNameChanged(newIndex);
-		}
+	const auto newIndex = chosenIndex();
+	if (newIndex != oldIndex && newIndex >= 0) {
+		accessibilityChildStateChanged(newIndex, { .checked = true });
+		accessibilityChildNameChanged(newIndex);
 	}
 }
 
 void Rows::setSelected(int selected) {
+	setSelected(selected, Announce::OnChange);
+}
+
+void Rows::setSelected(int selected, Announce announce) {
 	_mouseSelection = false;
 	const auto limit = count();
-	if (selected >= 0 && selected < limit) {
-		updateSelected(RowSelection{ selected });
+	const auto clamped = (selected >= 0 && selected < limit)
+		? selected
+		: -1;
+	const auto changed = (indexFromSelection(_selected) != clamped)
+		|| (clamped < 0 && !v::is_null(_selected));
+	if (clamped >= 0) {
+		updateSelected(RowSelection{ clamped });
 	} else {
 		updateSelected({});
 	}
-	if (selected >= 0 && selected < limit
-		&& base::ScreenReaderState::Instance()->active()) {
-		accessibilityChildNameChanged(selected);
-		accessibilityChildFocused(selected);
+	const auto shouldAnnounce = (announce == Announce::Always)
+		|| (announce == Announce::OnChange && changed);
+	if (shouldAnnounce && clamped >= 0) {
+		accessibilityChildNameChanged(clamped);
+		accessibilityChildFocused(clamped);
 	}
 }
 
@@ -1064,6 +1013,84 @@ void Rows::paintEvent(QPaintEvent *e) {
 	}
 }
 
+QAccessible::Role Rows::accessibilityRole() {
+	return QAccessible::List;
+}
+
+Qt::FocusPolicy Rows::accessibilityFocusPolicy() {
+	return Qt::TabFocus;
+}
+
+QAccessible::Role Rows::accessibilityChildRole() const {
+	return QAccessible::RadioButton;
+}
+
+QAccessible::State Rows::accessibilityChildState(int index) const {
+	QAccessible::State state;
+	if (Ui::ScreenReaderModeActive()) {
+		state.focusable = true;
+	}
+	state.checkable = true;
+	state.checked = (index == chosenIndex());
+	if (index == selected()) {
+		state.active = true;
+		if (hasFocus()) {
+			state.focused = true;
+		}
+	}
+	return state;
+}
+
+int Rows::accessibilityChildCount() const {
+	return count();
+}
+
+QString Rows::accessibilityChildName(int index) const {
+	if (index < 0 || index >= count()) {
+		return {};
+	}
+	const auto &row = rowByIndex(index);
+	return row.data.nativeName + u", "_q + row.data.name;
+}
+
+QRect Rows::accessibilityChildRect(int index) const {
+	if (index < 0 || index >= count()) {
+		return {};
+	}
+	const auto &row = rowByIndex(index);
+	return QRect(0, row.top, width(), row.height);
+}
+
+int Rows::accessibilityChildColumnCount(int row) const {
+	return 2;
+}
+
+QAccessible::Role Rows::accessibilityChildSubItemRole() const {
+	return QAccessible::Cell;
+}
+
+QString Rows::accessibilityChildSubItemName(int row, int column) const {
+	if (column == 0) {
+		return tr::lng_sr_languages_column_native(tr::now);
+	} else if (column == 1) {
+		return tr::lng_sr_languages_column_name(tr::now);
+	}
+	return {};
+}
+
+QString Rows::accessibilityChildSubItemValue(int row, int column) const {
+	if (row < 0 || row >= count()) {
+		return {};
+	}
+	const auto &data = rowByIndex(row).data;
+	if (column == 0) {
+		return data.nativeName;
+	} else if (column == 1) {
+		return data.name;
+	}
+	return {};
+}
+
 Content::Content(
 	QWidget *parent,
 	const Languages &recent,