vcl: support for Windows ITaskbarList3 interface

And a demo implementation for these features as a taskbar window
will become red once LO is displaying any error message.

Change-Id: Ifc04026c699059da2e457de2c69e7363e756109c
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/166740
Tested-by: Jenkins
Reviewed-by: Thorsten Behrens <thorsten.behrens@allotropia.de>

include/vcl/vclenum.hxx

@@ -196,6 +196,20 @@ enum class VclPackType
     LAST = End
 };
 
+enum class VclTaskBarStates {
+    // Default, no specifics
+    Normal,
+    // Display some progress defined by SetTaskBarProgress
+    Progress,
+    // Something going on, but no exact progress scale
+    ProgressUnknown,
+    // Process on pause
+    Paused,
+    // Some error did happen
+    Error
+};
+
+
 // Return Values from Dialog::Execute
 //!!! in case of changes adjust /basic/source/runtime/methods.cxx msgbox
 

include/vcl/window.hxx

@@ -1122,6 +1122,9 @@ public:
     /// Use OS specific way to bring user attention to current window
     virtual void FlashWindow() const;
 
+    virtual void SetTaskBarProgress(int nCurrentProgress);
+    virtual void SetTaskBarState(VclTaskBarStates eTaskBarState);
+
     /** @name Accessibility
      */
     ///@{

vcl/inc/salframe.hxx

@@ -316,6 +316,9 @@ public:
     // in nOffset, nChars.
     static Selection        CalcDeleteSurroundingSelection(std::u16string_view rSurroundingText,
                                                            sal_Int32 nCursorIndex, int nOffset, int nChars);
+
+    virtual void  SetTaskBarProgress(int /*nCurrentProgress*/) {}
+    virtual void  SetTaskBarState(VclTaskBarStates /*eTaskBarState*/) {}
 };
 
 #ifdef _WIN32

vcl/inc/win/salframe.h

@@ -29,10 +29,12 @@
 #include <svsys.h>
 
 class WinSalGraphics;
+struct ITaskbarList3;
 
 class WinSalFrame final: public SalFrame
 {
     vcl::WindowState m_eState;
+    ITaskbarList3* m_pTaskbarList3;
 
 public:
     HWND                    mhWnd;                  // Window handle
@@ -146,6 +148,9 @@ public:
     constexpr vcl::WindowState state() const { return m_eState; }
     void UpdateFrameState();
     constexpr bool isFullScreen() const { return bool(m_eState & vcl::WindowState::FullScreen); }
+
+    virtual void  SetTaskBarProgress(int nCurrentProgress) override;
+    virtual void  SetTaskBarState(VclTaskBarStates eTaskBarState) override;
 };
 
 void ImplSalGetWorkArea( HWND hWnd, RECT *pRect, const RECT *pParentRect );

vcl/source/window/layout.cxx

@@ -2563,6 +2563,7 @@ MessageDialog::MessageDialog(vcl::Window* pParent,
             break;
         case VclMessageType::Error:
             SetText(GetStandardErrorBoxText());
+            SetTaskBarState(VclTaskBarStates::Error);
             break;
         case VclMessageType::Other:
             SetText(Application::GetDisplayName());
@@ -2572,6 +2573,8 @@ MessageDialog::MessageDialog(vcl::Window* pParent,
 
 void MessageDialog::dispose()
 {
+    SetTaskBarState(VclTaskBarStates::Normal);
+
     disposeOwnedButtons();
     m_pPrimaryMessage.disposeAndClear();
     m_pSecondaryMessage.disposeAndClear();

vcl/source/window/window3.cxx

@@ -224,6 +224,22 @@ void Window::FlashWindow() const
         pMyParent->mpWindowImpl->mpFrame->FlashWindow();
 }
 
+void Window::SetTaskBarProgress(int nCurrentProgress)
+{
+    vcl::Window* pMyParent = ImplGetTopmostFrameWindow();
+
+    if (pMyParent && pMyParent->mpWindowImpl)
+        pMyParent->mpWindowImpl->mpFrame->SetTaskBarProgress(nCurrentProgress);
+}
+
+void Window::SetTaskBarState(VclTaskBarStates eTaskBarState)
+{
+    vcl::Window* pMyParent = ImplGetTopmostFrameWindow();
+
+    if (pMyParent && pMyParent->mpWindowImpl)
+        pMyParent->mpWindowImpl->mpFrame->SetTaskBarState(eTaskBarState);
+}
+
 } /* namespace vcl */
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

vcl/win/window/salframe.cxx

@@ -903,6 +903,7 @@ WinSalFrame::WinSalFrame()
     mpNextClipRect      = nullptr;
     mnDisplay           = 0;
     mbPropertiesStored  = false;
+    m_pTaskbarList3     = nullptr;
 
     // get data, when making 1st frame
     if ( !pSalData->mpFirstFrame )
@@ -985,6 +986,11 @@ WinSalFrame::~WinSalFrame()
         mpLocalGraphics = nullptr;
     }
 
+    if ( m_pTaskbarList3 )
+    {
+        m_pTaskbarList3->Release();
+    }
+
     if ( mhWnd )
     {
         // reset mouse leave data
@@ -3159,6 +3165,53 @@ bool WinSalFrame::GetUseReducedAnimation() const
     return !bEnableAnimation;
 }
 
+void WinSalFrame::SetTaskBarProgress(int nCurrentProgress)
+{
+    if (!m_pTaskbarList3)
+    {
+        HRESULT hr = CoCreateInstance(CLSID_TaskbarList, NULL, CLSCTX_INPROC_SERVER, IID_ITaskbarList3, (void **)&m_pTaskbarList3);
+        if (!SUCCEEDED(hr) || !m_pTaskbarList3)
+            return;
+    }
+
+    m_pTaskbarList3->SetProgressValue(mhWnd, nCurrentProgress, 100);
+}
+
+void WinSalFrame::SetTaskBarState(VclTaskBarStates eTaskBarState)
+{
+    if (!m_pTaskbarList3)
+    {
+        HRESULT hr = CoCreateInstance(CLSID_TaskbarList, NULL, CLSCTX_INPROC_SERVER, IID_ITaskbarList3, (void **)&m_pTaskbarList3);
+        if (!SUCCEEDED(hr) || !m_pTaskbarList3)
+            return;
+    }
+
+    TBPFLAG nFlag;
+    switch (eTaskBarState)
+    {
+        case VclTaskBarStates::Progress:
+            nFlag = TBPF_NORMAL;
+            break;
+        case VclTaskBarStates::ProgressUnknown:
+            nFlag = TBPF_INDETERMINATE;
+            break;
+        case VclTaskBarStates::Paused:
+            nFlag = TBPF_PAUSED;
+            SetTaskBarProgress(100);
+            break;
+        case VclTaskBarStates::Error:
+            nFlag = TBPF_ERROR;
+            SetTaskBarProgress(100);
+            break;
+        case VclTaskBarStates::Normal:
+        default:
+            nFlag = TBPF_NOPROGRESS;
+            break;
+    }
+
+    m_pTaskbarList3->SetProgressState(mhWnd, nFlag);
+}
+
 static bool ImplHandleMouseMsg( HWND hWnd, UINT nMsg,
                                 WPARAM wParam, LPARAM lParam )
 {