Update wxTreeCtrl and its sample to work with wxBitmapBundle

Override OnImagesChanged() to call UpdateImageListIfNecessary() even in
wxGenericTreeCtrl for now, although in the future it would really make
sense to stop using wxImageList in its implementation and just use
wxBitmapBundle directly instead.

wxMSW is the only one which really needs an image list, as it's required
by the native control.

Also update the sample, even though it doesn't look very nice because
its icons are only available in a single size, so we have to always
scale them.

include/wx/generic/treectlg.h

@@ -287,6 +287,9 @@ protected:
     // overridden wxWindow methods
     virtual void DoThaw() wxOVERRIDE;
 
+    virtual void OnImagesChanged() wxOVERRIDE;
+    void UpdateAfterImageListChange();
+
     // misc helpers
     void SendDeleteEvent(wxGenericTreeItem *itemBeingDeleted);
 

include/wx/msw/treectrl.h

@@ -212,6 +212,8 @@ protected:
 
     virtual bool MSWShouldSetDefaultFont() const wxOVERRIDE { return false; }
 
+    virtual void OnImagesChanged() wxOVERRIDE;
+
     // SetImageList helper
     void SetAnyImageList(wxImageList *imageList, int which);
 

include/wx/qt/treectrl.h

@@ -135,10 +135,14 @@ protected:
 
     virtual wxTreeItemId DoTreeHitTest(const wxPoint& point, int& flags) const wxOVERRIDE;
 
+    virtual void OnImagesChanged() wxOVERRIDE;
+
 private:
     void SendDeleteEvent(const wxTreeItemId &item);
     wxTreeItemId GetNext(const wxTreeItemId &item) const;
 
+    void DoUpdateIconsSize(wxImageList *imageList);
+
     wxQTreeWidget *m_qtTreeWidget;
     wxDECLARE_DYNAMIC_CLASS(wxTreeCtrl);
 };

samples/treectrl/treetest.cpp

@@ -688,7 +688,7 @@ void MyFrame::OnSetImageSize(wxCommandEvent& WXUNUSED(event))
     if ( size == -1 )
         return;
 
-    m_treeCtrl->CreateImageList(size);
+    m_treeCtrl->CreateImages(size);
     wxGetApp().SetShowImages(true);
 }
 
@@ -696,12 +696,12 @@ void MyFrame::OnToggleImages(wxCommandEvent& WXUNUSED(event))
 {
     if ( wxGetApp().ShowImages() )
     {
-        m_treeCtrl->CreateImageList(-1);
+        m_treeCtrl->CreateImages(-1);
         wxGetApp().SetShowImages(false);
     }
     else
     {
-        m_treeCtrl->CreateImageList(0);
+        m_treeCtrl->CreateImages(0);
         wxGetApp().SetShowImages(true);
     }
 }
@@ -730,7 +730,7 @@ void MyFrame::OnToggleAlternateImages(wxCommandEvent& WXUNUSED(event))
     bool alternateImages = m_treeCtrl->AlternateImages();
 
     m_treeCtrl->SetAlternateImages(!alternateImages);
-    m_treeCtrl->CreateImageList(0);
+    m_treeCtrl->CreateImages(0);
 }
 
 void MyFrame::OnToggleAlternateStates(wxCommandEvent& WXUNUSED(event))
@@ -955,14 +955,14 @@ MyTreeCtrl::MyTreeCtrl(wxWindow *parent, const wxWindowID id,
 {
     m_reverseSort = false;
 
-    CreateImageList();
+    CreateImages(16);
     CreateStateImageList();
 
     // Add some items to the tree
     AddTestItemsToTree(NUM_CHILDREN_PER_LEVEL, NUM_LEVELS);
 }
 
-void MyTreeCtrl::CreateImageList(int size)
+void MyTreeCtrl::CreateImages(int size)
 {
     if ( size == -1 )
     {
@@ -974,8 +974,7 @@ void MyTreeCtrl::CreateImageList(int size)
     else
         m_imageSize = size;
 
-    // Make an image list containing small icons
-    wxImageList *images = new wxImageList(size, size, true);
+    const wxSize iconSize(size, size);
 
     // should correspond to TreeCtrlIcon_xxx enum
     wxIcon icons[5];
@@ -990,8 +989,6 @@ void MyTreeCtrl::CreateImageList(int size)
     }
     else
     {
-        wxSize iconSize(size, size);
-
         icons[TreeCtrlIcon_File] =
         icons[TreeCtrlIcon_FileSelected] = wxArtProvider::GetIcon(wxART_NORMAL_FILE, wxART_LIST, iconSize);
         icons[TreeCtrlIcon_Folder] =
@@ -999,20 +996,50 @@ void MyTreeCtrl::CreateImageList(int size)
         icons[TreeCtrlIcon_FolderOpened] = wxArtProvider::GetIcon(wxART_FOLDER, wxART_LIST, iconSize);
     }
 
+    // Make a vector of bundles corresponding to the icons. We use a custom
+    // bundle implementation here as we always scale the icons, even at 100%
+    // DPI, to ensure they are of the desired size.
+    wxVector<wxBitmapBundle> images;
+
+    class FixedSizeImpl : public wxBitmapBundleImpl
+    {
+    public:
+        FixedSizeImpl(const wxSize& sizeDef, const wxIcon& icon)
+            : m_sizeDef(sizeDef),
+              m_icon(icon)
+        {
+        }
+
+        wxSize GetDefaultSize() const wxOVERRIDE
+        {
+            return m_sizeDef;
+        }
+
+        wxSize GetPreferredSizeAtScale(double scale) const wxOVERRIDE
+        {
+            return m_sizeDef*scale;
+        }
+
+        wxBitmap GetBitmap(const wxSize& size) wxOVERRIDE
+        {
+            wxBitmap bmp(m_icon);
+            if ( size != bmp.GetSize() )
+                wxBitmap::Rescale(bmp, size);
+
+            return bmp;
+        }
+
+    private:
+        const wxSize m_sizeDef;
+        const wxIcon m_icon;
+    };
+
     for ( size_t i = 0; i < WXSIZEOF(icons); i++ )
     {
-        int sizeOrig = icons[0].GetWidth();
-        if ( size == sizeOrig )
-        {
-            images->Add(icons[i]);
-        }
-        else
-        {
-            images->Add(wxBitmap(wxBitmap(icons[i]).ConvertToImage().Rescale(size, size)));
-        }
+        images.push_back(wxBitmapBundle::FromImpl(new FixedSizeImpl(iconSize, icons[i])));
     }
 
-    AssignImageList(images);
+    SetImages(images);
 }
 
 void MyTreeCtrl::CreateStateImageList(bool del)

samples/treectrl/treetest.h

@@ -107,7 +107,12 @@ public:
     void GetItemsRecursively(const wxTreeItemId& idParent,
                              wxTreeItemIdValue cookie = 0);
 
-    void CreateImageList(int size = 16);
+    // This function behaves differently depending on the value of size:
+    //  - If it's -1, it turns off the use of images entirely.
+    //  - If it's 0, it reuses the last used size.
+    //  - If it's strictly positive, it creates icons in this size.
+    void CreateImages(int size);
+
     void CreateButtonsImageList(int size = 11);
     void CreateStateImageList(bool del = false);
 

src/common/treebase.cpp

@@ -172,6 +172,7 @@ wxTreeCtrlBase::wxTreeCtrlBase()
     m_quickBestSize = true;
 
     Bind(wxEVT_CHAR_HOOK, &wxTreeCtrlBase::OnCharHook, this);
+    Bind(wxEVT_DPI_CHANGED, &wxTreeCtrlBase::WXHandleDPIChanged, this);
 }
 
 wxTreeCtrlBase::~wxTreeCtrlBase()

src/generic/treectlg.cpp

@@ -2424,9 +2424,18 @@ void wxGenericTreeCtrl::CalculateLineHeight()
         m_lineHeight += m_lineHeight/10;   // otherwise 10% extra spacing
 }
 
-void wxGenericTreeCtrl::SetImageList(wxImageList *imageList)
+void wxGenericTreeCtrl::OnImagesChanged()
+{
+    if ( HasImages() )
+    {
+        UpdateImageListIfNecessary(this);
+
+        UpdateAfterImageListChange();
+    }
+}
+
+void wxGenericTreeCtrl::UpdateAfterImageListChange()
 {
-    wxWithImages::SetImageList(imageList);
     m_dirty = true;
 
     if (m_anchor)
@@ -2434,33 +2443,26 @@ void wxGenericTreeCtrl::SetImageList(wxImageList *imageList)
 
     // Don't do any drawing if we're setting the list to NULL,
     // since we may be in the process of deleting the tree control.
-    if (imageList)
+    if (GetImageList())
         CalculateLineHeight();
 }
 
+void wxGenericTreeCtrl::SetImageList(wxImageList *imageList)
+{
+    wxWithImages::SetImageList(imageList);
+    UpdateAfterImageListChange();
+}
+
 void wxGenericTreeCtrl::SetStateImageList(wxImageList *imageList)
 {
     m_imagesState.SetImageList(imageList);
-    m_dirty = true;
-
-    if (m_anchor)
-        m_anchor->RecursiveResetSize();
-
-    // Don't do any drawing if we're setting the list to NULL,
-    // since we may be in the process of deleting the tree control.
-    if (imageList)
-        CalculateLineHeight();
+    UpdateAfterImageListChange();
 }
 
 void wxGenericTreeCtrl::SetButtonsImageList(wxImageList *imageList)
 {
     m_imagesButtons.SetImageList(imageList);
-    m_dirty = true;
-
-    if (m_anchor)
-        m_anchor->RecursiveResetSize();
-
-    CalculateLineHeight();
+    UpdateAfterImageListChange();
 }
 
 void wxGenericTreeCtrl::AssignButtonsImageList(wxImageList *imageList)

src/msw/treectrl.cpp

@@ -931,6 +931,24 @@ void wxTreeCtrl::SetStateImageList(wxImageList *imageList)
     SetAnyImageList(imageList, TVSIL_STATE);
 }
 
+void wxTreeCtrl::OnImagesChanged()
+{
+    wxImageList* imageList;
+
+    if ( HasImages() )
+    {
+        UpdateImageListIfNecessary(this);
+
+        imageList = GetImageList();
+    }
+    else
+    {
+        imageList = NULL;
+    }
+
+    SetAnyImageList(imageList, TVSIL_NORMAL);
+}
+
 size_t wxTreeCtrl::GetChildrenCount(const wxTreeItemId& item,
                                     bool recursively) const
 {

src/qt/treectrl.cpp

@@ -613,12 +613,27 @@ void wxTreeCtrl::SetImageList(wxImageList *imageList)
 {
     wxWithImages::SetImageList(imageList);
 
+    DoUpdateIconsSize(imageList);
+}
+
+void wxTreeCtrl::DoUpdateIconsSize(wxImageList *imageList)
+{
     int width, height;
     imageList->GetSize(0, width, height);
     m_qtTreeWidget->ResizeIcons(QSize(width, height));
     m_qtTreeWidget->update();
 }
 
+void wxTreeCtrl::OnImagesChanged()
+{
+    if ( HasImages() )
+    {
+        UpdateImageListIfNecessary(this);
+
+        DoUpdateIconsSize(GetImageList());
+    }
+}
+
 void wxTreeCtrl::SetStateImageList(wxImageList *imageList)
 {
     m_imagesState.SetImageList(imageList);