Added support to move Tabs from one UITabWidget to another using the onDrop API.

TODO.md

@@ -1,10 +1,6 @@
 
 # TODO - Short and mid term plans.
 
-## UITabWidget
-
-* Add support to move Tabs from one `UITabWidget` to another using the onDrop API.
-
 ## UIIconTheme and UIIconThemeManager
 
 Implement icon themes separated from the `UITheme` and customizable from a CSS file.

docs/articles/cssspecification.md

@@ -1564,6 +1564,16 @@ Enables/disables manually rearraging the tabs in the tab bar.
 
 ---
 
+### tabbar-allow-drag-and-drop-tabs
+
+Enables/disables the hability to move any tab from a TabWidget to another.
+
+* Applicable to: EE::UI::UITabWidget (TabWidget)
+* Data Type: [boolean](#boolean-data-type)
+* Default value: `false`
+
+---
+
 ### tab-closable
 
 Enables/disables tabs to be closable with the middle mouse button click or by clicking on the close

include/eepp/scene/event.hpp

@@ -52,6 +52,7 @@ class EE_API Event {
 		MsgBoxConfirmClick,
 		MsgBoxCancelClick,
 		OnTabSelected,
+		OnTabAdded,
 		OnTabClosed,
 		OnTabNavigate,
 		OnClose, // Warning: Only some nodes will report this event.

include/eepp/scene/node.hpp

@@ -371,7 +371,7 @@ class EE_API Node : public Transformable {
 
 	bool isChild( Node* child ) const;
 
-	bool inParentTreeOf( Node* Child ) const;
+	bool inParentTreeOf( Node* child ) const;
 
 	void setLoadingState( bool loading );
 

include/eepp/ui/css/propertydefinition.hpp

@@ -190,6 +190,7 @@ enum class PropertyId : Uint32 {
 	BorderBottomRightRadius = String::hash( "border-bottom-right-radius" ),
 	TabBarHideOnSingleTab = String::hash( "tabbar-hide-on-single-tab" ),
 	TabBarAllowRearrange = String::hash( "tabbar-allow-rearrange" ),
+	TabBarAllowDragAndDrop = String::hash( "tabbar-allow-drag-and-drop-tabs" ),
 };
 
 enum class PropertyType : Uint32 {

include/eepp/ui/uitab.hpp

@@ -43,6 +43,8 @@ class EE_API UITab : public UISelectButton {
 	String mText;
 	std::string mOwnedName;
 	UIWidget* mCloseButton;
+	Float mDragTotalDiff;
+	UITabWidget* mTabWidget;
 
 	Uint32 onDrag( const Vector2f& position, const Uint32& flags, const Sizef& dragDiff );
 

include/eepp/ui/uitabwidget.hpp

@@ -141,6 +141,14 @@ class EE_API UITabWidget : public UIWidget {
 
 	void setAllowRearrangeTabs( bool allowRearrangeTabs );
 
+	bool getAllowDragAndDropTabs() const;
+
+	void setAllowDragAndDropTabs( bool allowDragAndDropTabs );
+
+	const Float& getTabVerticalDragResistance() const;
+
+	void setTabVerticalDragResistance( const Float& tabVerticalDragResistance );
+
   protected:
 	friend class UITab;
 
@@ -153,17 +161,25 @@ class EE_API UITabWidget : public UIWidget {
 	TabTryCloseCallback mTabTryCloseCallback;
 	bool mHideTabBarOnSingleTab;
 	bool mAllowRearrangeTabs;
+	bool mAllowDragAndDropTabs;
+	Float mTabVerticalDragResistance;
 
 	void onThemeLoaded();
 
 	UITab* createTab( const String& text, UINode* nodeOwned, Drawable* icon );
 
+	void removeTab( const Uint32& index, bool destroyOwnedNode, bool destroyTab = true );
+
+	void removeTab( UITab* tab, bool destroyOwnedNode, bool destroyTab );
+
 	virtual void onSizeChange();
 
 	virtual void onChildCountChange( Node* child, const bool& removed );
 
 	virtual void onPaddingChange();
 
+	virtual Uint32 onMessage( const NodeMessage* msg );
+
 	void setContainerSize();
 
 	void posTabs();

src/eepp/scene/node.cpp

@@ -773,16 +773,13 @@ bool Node::isChild( Node* child ) const {
 	return false;
 }
 
-bool Node::inParentTreeOf( Node* Child ) const {
-	Node* ParentLoop = Child->mParentNode;
-
-	while ( NULL != ParentLoop ) {
-		if ( ParentLoop == this )
+bool Node::inParentTreeOf( Node* child ) const {
+	Node* node = child->mParentNode;
+	while ( NULL != node ) {
+		if ( node == this )
 			return true;
-
-		ParentLoop = ParentLoop->mParentNode;
+		node = node->mParentNode;
 	}
-
 	return false;
 }
 

src/eepp/scene/nodemessage.cpp

@@ -23,4 +23,8 @@ const Uint32& NodeMessage::getFlags() const {
 NodeDropMessage::NodeDropMessage( Node* node, const Uint32& msg, Node* droppedNode ) :
 	NodeMessage( node, msg ), mDroppedNode( droppedNode ) {}
 
+Node* NodeDropMessage::getDroppedNode() const {
+	return mDroppedNode;
+}
+
 }} // namespace EE::Scene

src/eepp/ui/css/stylesheetspecification.cpp

@@ -362,6 +362,7 @@ void StyleSheetSpecification::registerDefaultProperties() {
 
 	registerProperty( "tabbar-hide-on-single-tab", "false" );
 	registerProperty( "tabbar-allow-rearrange", "false" );
+	registerProperty( "tabbar-allow-drag-and-drop-tabs", "false" );
 
 	// Shorthands
 	registerShorthand( "margin", {"margin-top", "margin-right", "margin-bottom", "margin-left"},

src/eepp/ui/uinode.cpp

@@ -442,11 +442,7 @@ Uint32 UINode::onCalculateDrag( const Vector2f& position, const Uint32& flags )
 
 			if ( onDrag( pos, flags, dragDiff ) ) {
 				setPixelsPosition( mPosition - dragDiff );
-
 				mDragPoint = pos;
-
-				onPositionChange();
-
 				eventDispatcher->setNodeDragging( this );
 			}
 		}
@@ -1137,9 +1133,9 @@ void UINode::setDragging( const bool& dragging ) {
 		mEnabled = false;
 		Node* found = getUISceneNode()->overFind( getEventDispatcher()->getMousePosf() );
 		if ( found && found->isUINode() ) {
-			found->asType<UINode>()->onDrop( this );
 			NodeDropMessage msg( found, NodeMessage::Drop, this );
 			found->messagePost( &msg );
+			found->asType<UINode>()->onDrop( this );
 		}
 		mEnabled = enabled;
 	}

src/eepp/ui/uitab.cpp

@@ -9,7 +9,8 @@ UITab* UITab::New() {
 	return eeNew( UITab, () );
 }
 
-UITab::UITab() : UISelectButton( "tab" ), mOwnedWidget( NULL ) {
+UITab::UITab() :
+	UISelectButton( "tab" ), mOwnedWidget( NULL ), mDragTotalDiff( 0.f ), mTabWidget( NULL ) {
 	mTextBox->setElementTag( mTag + "::text" );
 	mIcon->setElementTag( mTag + "::icon" );
 	auto cb = [&]( const Event* ) { onSizeChange(); };
@@ -37,12 +38,13 @@ UITabWidget* UITab::getTabWidget() {
 	if ( NULL != getParent() && NULL != getParent()->getParent() &&
 		 getParent()->getParent()->isType( UI_TYPE_TABWIDGET ) ) {
 		return getParent()->getParent()->asType<UITabWidget>();
+	} else if ( mTabWidget ) {
+		return mTabWidget;
 	}
-
 	return NULL;
 }
 
-Uint32 UITab::onDrag( const Vector2f&, const Uint32&, const Sizef& dragDiff ) {
+Uint32 UITab::onDrag( const Vector2f& pos, const Uint32&, const Sizef& dragDiff ) {
 	UITabWidget* tabW = getTabWidget();
 	if ( !tabW )
 		return 0;
@@ -65,11 +67,27 @@ Uint32 UITab::onDrag( const Vector2f&, const Uint32&, const Sizef& dragDiff ) {
 			}
 		}
 	}
+	if ( tabW->getAllowDragAndDropTabs() && !( mFlags & UI_DRAG_VERTICAL ) ) {
+		mDragTotalDiff += ( Float )( mDragPoint.y - pos.y );
+		if ( eeabs( mDragTotalDiff ) >= tabW->getTabVerticalDragResistance() ) {
+			setFlags( UI_DRAG_VERTICAL );
+			setPixelsPosition( mPosition.x, mPosition.y - mDragTotalDiff );
+			mDragPoint = pos;
+			mTabWidget = getTabWidget();
+			Vector2f posDiff( pos );
+			worldToNode( posDiff );
+			setParent( getUISceneNode()->getRoot() );
+			setPixelsPosition( pos - posDiff );
+		}
+	}
 	return 1;
 }
 
 Uint32 UITab::onDragStart( const Vector2i& position, const Uint32& flags ) {
 	UITabWidget* tabW = getTabWidget();
+	mTabWidget = NULL;
+	mDragTotalDiff = 0;
+	unsetFlags( UI_DRAG_VERTICAL );
 	if ( tabW ) {
 		for ( size_t i = 0; i < tabW->getTabCount(); i++ ) {
 			UITab* tab = tabW->getTab( i );
@@ -83,6 +101,10 @@ Uint32 UITab::onDragStart( const Vector2i& position, const Uint32& flags ) {
 
 Uint32 UITab::onDragStop( const Vector2i& position, const Uint32& flags ) {
 	UITabWidget* tabW = getTabWidget();
+	if ( mTabWidget ) {
+		setParent( tabW->getTabBar() );
+		mTabWidget = NULL;
+	}
 	if ( tabW ) {
 		for ( size_t i = 0; i < tabW->getTabCount(); i++ ) {
 			UITab* tab = tabW->getTab( i );
@@ -303,7 +325,7 @@ void UITab::updateTab() {
 		} else {
 			UIPushButton::setText( mText );
 		}
-		setDragEnabled( tTabW->getAllowRearrangeTabs() );
+		setDragEnabled( tTabW->getAllowRearrangeTabs() || tTabW->getAllowDragAndDropTabs() );
 		onAutoSize();
 	}
 }

src/eepp/ui/uitabwidget.cpp

@@ -20,7 +20,9 @@ UITabWidget::UITabWidget() :
 	mTabSelected( NULL ),
 	mTabSelectedIndex( eeINDEX_NOT_FOUND ),
 	mHideTabBarOnSingleTab( false ),
-	mAllowRearrangeTabs( false ) {
+	mAllowRearrangeTabs( false ),
+	mAllowDragAndDropTabs( false ),
+	mTabVerticalDragResistance( PixelDensity::dpToPx( 64 ) ) {
 	setHorizontalAlign( UI_HALIGN_CENTER );
 
 	mTabBar = UIWidget::NewWithTag( "tabwidget::tabbar" );
@@ -218,6 +220,9 @@ bool UITabWidget::applyProperty( const StyleSheetProperty& attribute ) {
 		case PropertyId::TabBarAllowRearrange:
 			setAllowRearrangeTabs( attribute.asBool() );
 			break;
+		case PropertyId::TabBarAllowDragAndDrop:
+			setAllowDragAndDropTabs( attribute.asBool() );
+			break;
 		default:
 			return UIWidget::applyProperty( attribute );
 	}
@@ -424,6 +429,9 @@ UITabWidget* UITabWidget::add( UITab* tab ) {
 		orderTabs();
 	}
 
+	TabEvent tabEvent( this, tab, getTabIndex( tab ), Event::OnTabAdded );
+	sendEvent( &tabEvent );
+
 	return this;
 }
 
@@ -459,13 +467,19 @@ Uint32 UITabWidget::getTabCount() const {
 }
 
 void UITabWidget::removeTab( const Uint32& index, bool destroyOwnedNode ) {
+	removeTab( index, destroyOwnedNode, true );
+}
+
+void UITabWidget::removeTab( const Uint32& index, bool destroyOwnedNode, bool destroyTab ) {
 	eeASSERT( index < mTabs.size() );
 
 	UITab* tab = mTabs[index];
 
-	tab->close();
-	tab->setVisible( false );
-	tab->setEnabled( false );
+	if ( destroyTab ) {
+		tab->close();
+		tab->setVisible( false );
+		tab->setEnabled( false );
+	}
 	if ( destroyOwnedNode ) {
 		tab->getOwnedWidget()->close();
 		tab->getOwnedWidget()->setVisible( false );
@@ -499,7 +513,11 @@ void UITabWidget::removeTab( const Uint32& index, bool destroyOwnedNode ) {
 }
 
 void UITabWidget::removeTab( UITab* tab, bool destroyOwnedNode ) {
-	removeTab( getTabIndex( tab ), destroyOwnedNode );
+	removeTab( getTabIndex( tab ), destroyOwnedNode, true );
+}
+
+void UITabWidget::removeTab( UITab* tab, bool destroyOwnedNode, bool destroyTab ) {
+	removeTab( getTabIndex( tab ), destroyOwnedNode, destroyTab );
 }
 
 void UITabWidget::removeAllTabs( bool destroyOwnedNode ) {
@@ -628,6 +646,22 @@ void UITabWidget::setAllowRearrangeTabs( bool allowRearrangeTabs ) {
 	}
 }
 
+bool UITabWidget::getAllowDragAndDropTabs() const {
+	return mAllowDragAndDropTabs;
+}
+
+void UITabWidget::setAllowDragAndDropTabs( bool allowDragAndDropTabs ) {
+	mAllowDragAndDropTabs = allowDragAndDropTabs;
+}
+
+const Float& UITabWidget::getTabVerticalDragResistance() const {
+	return mTabVerticalDragResistance;
+}
+
+void UITabWidget::setTabVerticalDragResistance( const Float& tabVerticalDragResistance ) {
+	mTabVerticalDragResistance = tabVerticalDragResistance;
+}
+
 void UITabWidget::refreshOwnedWidget( UITab* tab ) {
 	if ( NULL != tab && NULL != tab->getOwnedWidget() ) {
 		tab->getOwnedWidget()->setParent( mNodeContainer );
@@ -695,17 +729,24 @@ void UITabWidget::onSizeChange() {
 void UITabWidget::onChildCountChange( Node* child, const bool& removed ) {
 	if ( !removed && child != mTabBar && child != mNodeContainer ) {
 		if ( child->isType( UI_TYPE_TAB ) ) {
-			UITab* Tab = static_cast<UITab*>( child );
+			// This must be a tab that was dragging.
+			if ( std::find( mTabs.begin(), mTabs.end(), child->asType<UITab>() ) != mTabs.end() )
+				return;
 
-			Tab->setParent( mTabBar );
+			UITab* tab = static_cast<UITab*>( child );
 
-			mTabs.push_back( Tab );
+			tab->setParent( mTabBar );
+
+			mTabs.push_back( tab );
 
 			if ( NULL == mTabSelected ) {
-				setTabSelected( Tab );
+				setTabSelected( tab );
 			} else {
 				orderTabs();
 			}
+
+			TabEvent tabEvent( this, tab, getTabIndex( tab ), Event::OnTabAdded );
+			sendEvent( &tabEvent );
 		} else {
 			child->setParent( mNodeContainer );
 			child->setVisible( false );
@@ -722,6 +763,21 @@ void UITabWidget::onPaddingChange() {
 	UIWidget::onPaddingChange();
 }
 
+Uint32 UITabWidget::onMessage( const NodeMessage* msg ) {
+	if ( msg->getMsg() == NodeMessage::Drop && mAllowDragAndDropTabs ) {
+		const NodeDropMessage* dropMsg = static_cast<const NodeDropMessage*>( msg );
+		if ( dropMsg->getDroppedNode()->isType( UI_TYPE_TAB ) ) {
+			UITab* tab = dropMsg->getDroppedNode()->asType<UITab>();
+			if ( tab->getTabWidget() != this ) {
+				tab->getTabWidget()->removeTab( tab, false, false );
+				add( tab );
+				return 1;
+			}
+		}
+	}
+	return 0;
+}
+
 void UITabWidget::applyThemeToTabs() {
 	if ( mStyleConfig.TabsEdgesDiffSkins ) {
 		for ( Uint32 i = 0; i < mTabs.size(); i++ ) {

src/tools/codeeditor/codeeditor.cpp

@@ -451,6 +451,7 @@ UITabWidget* App::createEditorWithTabWidget( Node* parent ) {
 	tabWidget->setTabsClosable( true );
 	tabWidget->setHideTabBarOnSingleTab( true );
 	tabWidget->setAllowRearrangeTabs( true );
+	tabWidget->setAllowDragAndDropTabs( true );
 	tabWidget->addEventListener( Event::OnTabSelected, [&]( const Event* event ) {
 		UITabWidget* tabWidget = event->getNode()->asType<UITabWidget>();
 		mCurEditor = tabWidget->getTabSelected()->getOwnedWidget()->asType<UICodeEditor>();
@@ -463,6 +464,16 @@ UITabWidget* App::createEditorWithTabWidget( Node* parent ) {
 	tabWidget->addEventListener( Event::OnTabClosed, [&]( const Event* event ) {
 		onTabClosed( static_cast<const TabEvent*>( event ) );
 	} );
+	tabWidget->addEventListener( Event::OnTabAdded, [&]( const Event* event ) {
+		UITabWidget* tabWidget = event->getNode()->asType<UITabWidget>();
+		if ( tabWidget->getTabCount() == 2 && tabWidget->getTab( 0 )
+												  ->getOwnedWidget()
+												  ->asType<UICodeEditor>()
+												  ->getDocument()
+												  .isEmpty() ) {
+			tabWidget->removeTab( (Uint32)0 );
+		}
+	} );
 	createCodeEditorInTabWidget( tabWidget );
 	mTabWidgets.push_back( tabWidget );
 	return tabWidget;
@@ -508,13 +519,6 @@ void App::openFileDialog() {
 		UITab* addedTab = d.first;
 		loadFileFromPath( event->getNode()->asType<UIFileDialog>()->getFullPath(), d.second );
 		tabWidget->setTabSelected( addedTab );
-		UITab* firstTab = tabWidget->getTab( 0 );
-		if ( addedTab != firstTab ) {
-			UICodeEditor* editor = (UICodeEditor*)firstTab->getOwnedWidget();
-			if ( editor->getDocument().isEmpty() ) {
-				tabWidget->removeTab( firstTab );
-			}
-		}
 	} );
 	dialog->addEventListener( Event::OnWindowClose, [&]( const Event* ) {
 		if ( mCurEditor && !SceneManager::instance()->isShootingDown() )