From d3e8eb429201b2966b384a95bae6bc7f42f55cf7 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Fri, 20 Sep 2019 10:35:47 +0300
Subject: [PATCH] Add LayerManager for any RpWidget.

---
 gyp/sources.txt             |  2 +
 ui/layers/layer_manager.cpp | 85 +++++++++++++++++++++++++++++++++++++
 ui/layers/layer_manager.h   | 41 ++++++++++++++++++
 3 files changed, 128 insertions(+)
 create mode 100644 ui/layers/layer_manager.cpp
 create mode 100644 ui/layers/layer_manager.h

diff --git a/gyp/sources.txt b/gyp/sources.txt
index 9183f28..eeaedcc 100644
--- a/gyp/sources.txt
+++ b/gyp/sources.txt
@@ -22,6 +22,8 @@
 <(src_loc)/ui/layers/box_layer_widget.h
 <(src_loc)/ui/layers/generic_box.cpp
 <(src_loc)/ui/layers/generic_box.h
+<(src_loc)/ui/layers/layer_manager.cpp
+<(src_loc)/ui/layers/layer_manager.h
 <(src_loc)/ui/layers/layer_widget.cpp
 <(src_loc)/ui/layers/layer_widget.h
 <(src_loc)/ui/platform/ui_platform_utility.h
diff --git a/ui/layers/layer_manager.cpp b/ui/layers/layer_manager.cpp
new file mode 100644
index 0000000..d44e89e
--- /dev/null
+++ b/ui/layers/layer_manager.cpp
@@ -0,0 +1,85 @@
+// This file is part of Desktop App Toolkit,
+// a set of libraries for developing nice desktop applications.
+//
+// For license and copyright information please follow this link:
+// https://github.com/desktop-app/legal/blob/master/LEGAL
+//
+#include "ui/layers/layer_manager.h"
+
+namespace Ui {
+
+LayerManager::LayerManager(not_null<RpWidget*> widget) : _widget(widget) {
+}
+
+void LayerManager::setHideByBackgroundClick(bool hide) {
+	_hideByBackgroundClick = hide;
+	if (_layer) {
+		_layer->setHideByBackgroundClick(hide);
+	}
+}
+
+void LayerManager::showBox(
+		object_ptr<BoxContent> box,
+		LayerOptions options,
+		anim::type animated) {
+	ensureLayerCreated();
+	_layer->showBox(std::move(box), options, animated);
+}
+
+void LayerManager::hideAll(anim::type animated) {
+	if (animated == anim::type::instant) {
+		destroyLayer();
+	} else if (_layer) {
+		_layer->hideAll(animated);
+	}
+}
+
+void LayerManager::raise() {
+	if (_layer) {
+		_layer->raise();
+	}
+}
+
+bool LayerManager::setFocus() {
+	if (!_layer) {
+		return false;
+	}
+	_layer->setInnerFocus();
+	return true;
+}
+
+void LayerManager::ensureLayerCreated() {
+	if (_layer) {
+		return;
+	}
+	_layer.emplace(_widget);
+	_layer->setHideByBackgroundClick(_hideByBackgroundClick);
+
+	_layer->hideFinishEvents(
+	) | rpl::filter([=] {
+		return _layer != nullptr; // Last hide finish is sent from destructor.
+	}) | rpl::start_with_next([=] {
+		destroyLayer();
+	}, _layer->lifetime());
+
+	_layer->move(0, 0);
+	_widget->sizeValue(
+	) | rpl::start_with_next([=](QSize size) {
+		_layer->resize(size);
+	}, _layer->lifetime());
+}
+
+void LayerManager::destroyLayer() {
+	if (!_layer) {
+		return;
+	}
+
+	auto layer = base::take(_layer);
+	const auto resetFocus = Ui::InFocusChain(layer);
+	if (resetFocus) {
+		_widget->setFocus();
+	}
+	layer = nullptr;
+}
+
+} // namespace Ui
diff --git a/ui/layers/layer_manager.h b/ui/layers/layer_manager.h
new file mode 100644
index 0000000..1f0d31e
--- /dev/null
+++ b/ui/layers/layer_manager.h
@@ -0,0 +1,41 @@
+// This file is part of Desktop App Toolkit,
+// a set of libraries for developing nice desktop applications.
+//
+// For license and copyright information please follow this link:
+// https://github.com/desktop-app/legal/blob/master/LEGAL
+//
+#pragma once
+
+#include "ui/layers/layer_widget.h"
+
+#include <QtCore/QMargins>
+
+namespace Ui {
+
+class BoxContent;
+class RpWidget;
+
+class LayerManager final {
+public:
+	explicit LayerManager(not_null<RpWidget*> widget);
+
+	void setHideByBackgroundClick(bool hide);
+	void showBox(
+		object_ptr<BoxContent> box,
+		LayerOptions options = LayerOption::KeepOther,
+		anim::type animated = anim::type::normal);
+	void hideAll(anim::type animated = anim::type::normal);
+	void raise();
+	bool setFocus();
+
+private:
+	void ensureLayerCreated();
+	void destroyLayer();
+
+	const not_null<RpWidget*> _widget;
+	base::unique_qptr<LayerStackWidget> _layer;
+	bool _hideByBackgroundClick = false;
+
+};
+
+} // namespace Ui