Merge pull request #8487 from unknownbrackets/ui-tweaks

Retain focus in UI on resize, disable scroll to top

ext/native/ui/ui_screen.cpp

@@ -23,7 +23,7 @@ void UIScreen::DoRecreateViews() {
 		UI::PersistMap persisted;
 		bool persisting = root_ != nullptr;
 		if (persisting) {
-			root_->PersistData(UI::PERSIST_SAVE, persisted);
+			root_->PersistData(UI::PERSIST_SAVE, "root", persisted);
 		}
 
 		delete root_;
@@ -34,8 +34,16 @@ void UIScreen::DoRecreateViews() {
 		}
 		recreateViews_ = false;
 
-		if (persisting) {
-			root_->PersistData(UI::PERSIST_RESTORE, persisted);
+		if (persisting && root_ != nullptr) {
+			root_->PersistData(UI::PERSIST_RESTORE, "root", persisted);
+
+			// Update layout and refocus so things scroll into view.
+			// This is for resizing down, when focused on something now offscreen.
+			UI::LayoutViewHierarchy(*screenManager()->getUIContext(), root_);
+			UI::View *focused = UI::GetFocusedView();
+			if (focused) {
+				root_->SubviewFocused(focused);
+			}
 		}
 	}
 }

ext/native/ui/view.cpp

@@ -164,6 +164,28 @@ std::string View::Describe() const {
 }
 
 
+void View::PersistData(PersistStatus status, std::string anonId, PersistMap &storage) {
+	// Remember if this view was a focused view.
+	std::string tag = Tag();
+	if (tag.empty()) {
+		tag = anonId;
+	}
+
+	const std::string focusedKey = "ViewFocused::" + tag;
+	switch (status) {
+	case UI::PERSIST_SAVE:
+		if (HasFocus()) {
+			storage[focusedKey].resize(1);
+		}
+		break;
+	case UI::PERSIST_RESTORE:
+		if (storage.find(focusedKey) != storage.end()) {
+			SetFocus();
+		}
+		break;
+	}
+}
+
 Point View::GetFocusPosition(FocusDirection dir) {
 	// The +2/-2 is some extra fudge factor to cover for views sitting right next to each other.
 	// Distance zero yields strange results otherwise.

ext/native/ui/view.h

@@ -346,7 +346,7 @@ public:
 	virtual std::string Describe() const;
 
 	virtual void FocusChanged(int focusFlags) {}
-	virtual void PersistData(PersistStatus status, PersistMap &storage) {}
+	virtual void PersistData(PersistStatus status, std::string anonId, PersistMap &storage);
 
 	void Move(Bounds bounds) {
 		bounds_ = bounds;
@@ -388,7 +388,7 @@ public:
 	void SetEnabledPtr(bool *enabled) { enabledPtr_ = enabled; enabledMeansDisabled_ = false; }
 	void SetDisabledPtr(bool *disabled) { enabledPtr_ = disabled; enabledMeansDisabled_ = true;  }
 
-	void SetVisibility(Visibility visibility) { visibility_ = visibility; }
+	virtual void SetVisibility(Visibility visibility) { visibility_ = visibility; }
 	Visibility GetVisibility() const { return visibility_; }
 
 	const std::string &Tag() const { return tag_; }

ext/native/ui/viewgroup.cpp

@@ -3,6 +3,7 @@
 #include "base/functional.h"
 #include "base/logging.h"
 #include "base/mutex.h"
+#include "base/stringutil.h"
 #include "base/timeutil.h"
 #include "input/keycodes.h"
 #include "ui/ui_context.h"
@@ -75,10 +76,17 @@ void ViewGroup::Clear() {
 	views_.clear();
 }
 
-void ViewGroup::PersistData(PersistStatus status, PersistMap &storage) {
+void ViewGroup::PersistData(PersistStatus status, std::string anonId, PersistMap &storage) {
 	lock_guard guard(modifyLock_);
+
+	std::string tag = Tag();
+	if (tag.empty()) {
+		tag = anonId;
+	}
+
+	ITOA stringify;
 	for (size_t i = 0; i < views_.size(); i++) {
-		views_[i]->PersistData(status, storage);
+		views_[i]->PersistData(status, tag + "/" + stringify.p((int)i), storage);
 	}
 }
 
@@ -812,12 +820,12 @@ bool ScrollView::SubviewFocused(View *view) {
 	return true;
 }
 
-void ScrollView::PersistData(PersistStatus status, PersistMap &storage) {
-	ViewGroup::PersistData(status, storage);
+void ScrollView::PersistData(PersistStatus status, std::string anonId, PersistMap &storage) {
+	ViewGroup::PersistData(status, anonId, storage);
 
-	const std::string &tag = Tag();
+	std::string tag = Tag();
 	if (tag.empty()) {
-		return;
+		tag = anonId;
 	}
 
 	PersistBuffer &buffer = storage["ScrollView::" + tag];
@@ -843,6 +851,16 @@ void ScrollView::PersistData(PersistStatus status, PersistMap &storage) {
 	}
 }
 
+void ScrollView::SetVisibility(Visibility visibility) {
+	ViewGroup::SetVisibility(visibility);
+
+	if (visibility == V_GONE) {
+		// Since this is no longer shown, forget the scroll position.
+		// For example, this happens when switching tabs.
+		ScrollTo(0.0f);
+	}
+}
+
 void ScrollView::ScrollTo(float newScrollPos) {
 	scrollTarget_ = newScrollPos;
 	scrollToTarget_ = true;
@@ -1084,12 +1102,12 @@ EventReturn TabHolder::OnTabClick(EventParams &e) {
 	return EVENT_DONE;
 }
 
-void TabHolder::PersistData(PersistStatus status, PersistMap &storage) {
-	ViewGroup::PersistData(status, storage);
+void TabHolder::PersistData(PersistStatus status, std::string anonId, PersistMap &storage) {
+	ViewGroup::PersistData(status, anonId, storage);
 
-	const std::string &tag = Tag();
+	std::string tag = Tag();
 	if (tag.empty()) {
-		return;
+		tag = anonId;
 	}
 
 	PersistBuffer &buffer = storage["TabHolder::" + tag];

ext/native/ui/viewgroup.h

@@ -64,7 +64,7 @@ public:
 	virtual void SetBG(const Drawable &bg) { bg_ = bg; }
 
 	virtual void Clear();
-	void PersistData(PersistStatus status, PersistMap &storage) override;
+	void PersistData(PersistStatus status, std::string anonId, PersistMap &storage) override;
 	View *GetViewByIndex(int index) { return views_[index]; }
 	int GetNumSubviews() const { return (int)views_.size(); }
 	void SetHasDropShadow(bool has) { hasDropShadow_ = has; }
@@ -228,7 +228,7 @@ public:
 		scrollToTarget_(false),
 		inertia_(0),
 		lastViewSize_(0.0f),
-		scrollToTopOnSizeChange_(true) {}
+		scrollToTopOnSizeChange_(false) {}
 
 	void Measure(const UIContext &dc, MeasureSpec horiz, MeasureSpec vert) override;
 	void Layout() override;
@@ -246,8 +246,8 @@ public:
 
 	// Override so that we can scroll to the active one after moving the focus.
 	bool SubviewFocused(View *view) override;
-
-	void PersistData(PersistStatus status, PersistMap &storage) override;
+	void PersistData(PersistStatus status, std::string anonId, PersistMap &storage) override;
+	void SetVisibility(Visibility visibility) override;
 
 	// Quick hack to prevent scrolling to top in some lists
 	void SetScrollToTop(bool t) { scrollToTopOnSizeChange_ = t; }
@@ -316,16 +316,18 @@ public:
 	}
 
 	void SetCurrentTab(int tab) {
-		tabs_[currentTab_]->SetVisibility(V_GONE);
-		currentTab_ = tab;
-		tabs_[currentTab_]->SetVisibility(V_VISIBLE);
+		if (tab != currentTab_) {
+			tabs_[currentTab_]->SetVisibility(V_GONE);
+			currentTab_ = tab;
+			tabs_[currentTab_]->SetVisibility(V_VISIBLE);
+		}
 		tabStrip_->SetSelection(tab);
 	}
 
 	int GetCurrentTab() const { return currentTab_; }
 	std::string Describe() const override { return "TabHolder: " + View::Describe(); }
 
-	void PersistData(PersistStatus status, PersistMap &storage) override;
+	void PersistData(PersistStatus status, std::string anonId, PersistMap &storage) override;
 
 private:
 	EventReturn OnTabClick(EventParams &e);