Show new tab preview to be docked in other Tabs

src/app/ui/main_window.cpp

@@ -298,9 +298,9 @@ void MainWindow::onMouseOverTab(Tabs* tabs, TabView* tabView)
   }
 }
 
-void MainWindow::onFloatingTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos)
+DropViewPreviewResult MainWindow::onFloatingTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos)
 {
-  m_workspace->setDropViewPreview(pos,
+  return m_workspace->setDropViewPreview(pos,
     dynamic_cast<WorkspaceView*>(tabView),
     static_cast<WorkspaceTabs*>(tabs));
 }

src/app/ui/main_window.h

@@ -79,7 +79,7 @@ namespace app {
     void onCloseTab(Tabs* tabs, TabView* tabView) override;
     void onContextMenuTab(Tabs* tabs, TabView* tabView) override;
     void onMouseOverTab(Tabs* tabs, TabView* tabView) override;
-    void onFloatingTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos) override;
+    DropViewPreviewResult onFloatingTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos) override;
     void onDockingTab(Tabs* tabs, TabView* tabView) override;
     DropTabResult onDropTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos) override;
 

src/app/ui/tabs.cpp

@@ -240,15 +240,19 @@ void Tabs::setDropViewPreview(const gfx::Point& pos, TabView* view)
   else
     newIndex = 0;
 
-  if (m_dropNewIndex == newIndex && m_dropNewTab == view)
-    return;
+  bool startAni = (m_dropNewIndex != newIndex || m_dropNewTab != view);
 
   m_dropNewIndex = newIndex;
+  m_dropNewPosX = (pos.x - getBounds().x);
   m_dropNewTab = view;
 
-  resetOldPositions(animationTime());
-  updateTabs();
-  startAnimation(ANI_REORDER_TABS, ANI_REORDER_TABS_TICKS);
+  if (startAni) {
+    resetOldPositions(animationTime());
+    updateTabs();
+    startAnimation(ANI_REORDER_TABS, ANI_REORDER_TABS_TICKS);
+  }
+  else
+    invalidate();
 }
 
 void Tabs::removeDropViewPreview()
@@ -286,19 +290,27 @@ bool Tabs::onProcessMessage(Message* msg)
         // We are drag a tab...
         else {
           TabPtr justDocked(nullptr);
+          bool dockedInThisTabs = true;
 
           // Floating tab (to create a new window)
           if (!getBounds().contains(mousePos) &&
               (ABS(delta.y) > 16*guiscale() ||
                 mousePos.x < getBounds().x-16*guiscale() ||
                 mousePos.x > getBounds().x2()+16*guiscale())) {
-            if (!m_floatingOverlay)
-              createFloatingTab(m_selected);
-
-            m_floatingOverlay->moveOverlay(mousePos - m_dragOffset);
+            DropViewPreviewResult result = DropViewPreviewResult::FLOATING;
 
             if (m_delegate)
-              m_delegate->onFloatingTab(this, m_selected->view, mousePos);
+              result = m_delegate->onFloatingTab(this, m_selected->view, mousePos);
+
+            if (result != DropViewPreviewResult::DROP_IN_TABS) {
+              if (!m_floatingOverlay)
+                createFloatingTab(m_selected);
+              m_floatingOverlay->moveOverlay(mousePos - m_dragOffset);
+              dockedInThisTabs = false;
+            }
+            else {
+              destroyFloatingOverlay();
+            }
           }
           else {
             justDocked = m_floatingTab;
@@ -309,7 +321,7 @@ bool Tabs::onProcessMessage(Message* msg)
           }
 
           // Docked tab
-          if (!m_floatingOverlay) {
+          if (dockedInThisTabs) {
             m_selected->x = m_dragTabX + delta.x;
 
             int i = (mousePos.x - m_border*guiscale() - getBounds().x) / m_selected->width;
@@ -474,6 +486,19 @@ void Tabs::onPaint(PaintEvent& ev)
 
     drawTab(g, box, m_selected.get(), dy, (tab == m_hot), true);
   }
+
+  // New tab from other Tab that want to be dropped here.
+  if (m_dropNewTab) {
+    SkinTheme* theme = static_cast<SkinTheme*>(this->getTheme());
+    Tab newTab(m_dropNewTab);
+    newTab.text = m_dropNewTab->getTabText();
+    newTab.icon = m_dropNewTab->getTabIcon();
+    newTab.width = (!m_list.empty() ? m_list[0]->width:
+                    theme->dimensions.tabsWidth());
+    newTab.x = m_dropNewPosX - newTab.width/2;
+    box = getTabBounds(&newTab);
+    drawTab(g, box, &newTab, 0, true, true);
+  }
 }
 
 void Tabs::onResize(ResizeEvent& ev)
@@ -830,10 +855,7 @@ void Tabs::createFloatingTab(TabPtr& tab)
 
 void Tabs::destroyFloatingTab()
 {
-  if (m_floatingOverlay) {
-    OverlayManager::instance()->removeOverlay(m_floatingOverlay.get());
-    m_floatingOverlay.reset();
-  }
+  destroyFloatingOverlay();
 
   if (m_floatingTab) {
     TabPtr tab(m_floatingTab);
@@ -848,4 +870,12 @@ void Tabs::destroyFloatingTab()
   }
 }
 
+void Tabs::destroyFloatingOverlay()
+{
+  if (m_floatingOverlay) {
+    OverlayManager::instance()->removeOverlay(m_floatingOverlay.get());
+    m_floatingOverlay.reset();
+  }
+}
+
 } // namespace app

src/app/ui/tabs.h

@@ -49,6 +49,12 @@ namespace app {
     DOCKED_IN_OTHER_PLACE,
   };
 
+  enum class DropViewPreviewResult {
+    DROP_IN_PANEL,
+    DROP_IN_TABS,
+    FLOATING,
+  };
+
   // Interface used to control notifications from the Tabs widget.
   class TabsDelegate {
   public:
@@ -71,9 +77,13 @@ namespace app {
     // mouse just leave all tabs)
     virtual void onMouseOverTab(Tabs* tabs, TabView* tabView) = 0;
 
-    // Called when the user is dragging a tab outside the Tabs bar.
-    virtual void onFloatingTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos) = 0;
+    // Called when the user is dragging a tab outside the Tabs
+    // bar.
+    virtual DropViewPreviewResult onFloatingTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos) = 0;
+
+    // Called when the user is dragging a tab inside the Tabs bar.
     virtual void onDockingTab(Tabs* tabs, TabView* tabView) = 0;
+
     virtual DropTabResult onDropTab(Tabs* tabs, TabView* tabView, const gfx::Point& pos) = 0;
   };
 
@@ -154,6 +164,7 @@ namespace app {
     gfx::Rect getTabBounds(Tab* tab);
     void createFloatingTab(TabPtr& tab);
     void destroyFloatingTab();
+    void destroyFloatingOverlay();
 
     int m_border;
     TabsList m_list;
@@ -185,6 +196,7 @@ namespace app {
     // Drop new tabs
     TabView* m_dropNewTab;
     int m_dropNewIndex;
+    int m_dropNewPosX;
   };
 
 } // namespace app

src/app/ui/workspace.cpp

@@ -130,7 +130,7 @@ void Workspace::onResize(ui::ResizeEvent& ev)
     child->setBounds(rc);
 }
 
-void Workspace::setDropViewPreview(const gfx::Point& pos,
+DropViewPreviewResult Workspace::setDropViewPreview(const gfx::Point& pos,
   WorkspaceView* view, WorkspaceTabs* tabs)
 {
   TabView* tabView = dynamic_cast<TabView*>(view);
@@ -155,6 +155,13 @@ void Workspace::setDropViewPreview(const gfx::Point& pos,
     m_dropPreviewPanel->setDropViewPreview(pos, view);
   if (m_dropPreviewTabs)
     m_dropPreviewTabs->setDropViewPreview(pos, tabView);
+
+  if (panel)
+    return DropViewPreviewResult::DROP_IN_PANEL;
+  else if (newTabs)
+    return DropViewPreviewResult::DROP_IN_TABS;
+  else
+    return DropViewPreviewResult::FLOATING;
 }
 
 void Workspace::removeDropViewPreview()

src/app/ui/workspace.h

@@ -9,6 +9,7 @@
 #define APP_UI_WORKSPACE_H_INCLUDED
 #pragma once
 
+#include "app/ui/tabs.h"
 #include "app/ui/workspace_panel.h"
 #include "base/signal.h"
 #include "ui/widget.h"
@@ -43,8 +44,9 @@ namespace app {
     void selectNextTab();
     void selectPreviousTab();
 
-    // Drop views into workspace
-    void setDropViewPreview(const gfx::Point& pos,
+    // Set the preview of what could happen if we drop the given
+    // "view" at the "pos"?
+    DropViewPreviewResult setDropViewPreview(const gfx::Point& pos,
       WorkspaceView* view, WorkspaceTabs* tabs);
     void removeDropViewPreview();