IconView: Use an internal cache to speed up item text formatting.

[GB.GUI.BASE]
* OPT: IconView: Use an internal cache to speed up item text formatting.

comp/src/gb.gui.base/.project

@@ -1,6 +1,6 @@
 # Gambas Project File 3.0
 Title=Common controls and classes for GUI components
-Startup=FLabel
+Startup=FTestIconView
 Icon=.hidden/window.png
 Version=3.16.90
 VersionFile=1
@@ -8,7 +8,7 @@ Component=gb.image
 Component=gb.gui
 Component=gb.settings
 Arguments=[["-style=oxygen"],["-style=qtcurve"]]
-Environment="GB_JIT_DEBUG=1\nGB_GUI=gb.gtk3\nLIBOVERLAY_SCROLLBAR=0\n GTK_DEBUG=interactive"
+Environment="GB_JIT_DEBUG=1\nGB_GUI=gb.qt5\nLIBOVERLAY_SCROLLBAR=0\n GTK_DEBUG=interactive"
 TabSize=2
 Translate=1
 Language=en

comp/src/gb.gui.base/.src/IconView/IconView.class

@@ -107,6 +107,8 @@ Private $fFindTime As Float
 Private $iLock As Integer
 Private $hArrangeTimer As Timer
 
+Private $cTrimTextCache As New Collection
+
 Public Sub _new()
   
   $hView = New ScrollArea(Me) As "ScrollArea"
@@ -534,6 +536,8 @@ Public Sub ScrollArea_Arrange()
   Dim W, H As Integer
   Dim nRow As Integer
   Dim DS As Integer
+  Dim iOldGridHeight As Integer
+  Dim iOldGridWidth As Integer
   
   If $iLock Then Return
   
@@ -550,6 +554,9 @@ Public Sub ScrollArea_Arrange()
   
   ExitRename
   
+  iOldGridHeight = $iGridHeight
+  iOldGridWidth = $iGridWidth
+  
   If $bHorizontal Then
     
     $iGridHeight = Max(DS, $iIconSize) + DS * 2
@@ -594,6 +601,8 @@ Public Sub ScrollArea_Arrange()
 
   Endif
   
+  If iOldGridWidth <> $iGridWidth Or If iOldGridHeight <> $iGridHeight Then $cTrimTextCache.Clear
+  
 End
 
 Public Sub ScrollArea_Resize()
@@ -1620,6 +1629,8 @@ Public Sub ScrollArea_Font()
 
   Dim hItem As _IconView_Item
   
+  $cTrimTextCache.Clear
+  
   For Each hItem In $aItems
     hItem._Invalidate
   Next
@@ -1628,6 +1639,12 @@ Public Sub ScrollArea_Font()
 
 End
 
+Public Sub _GetTrimTextCache() As Collection
+  
+  Return $cTrimTextCache
+  
+End
+
 Private Function Keys_Read() As String[]
 
   Dim aKeys As New String[]

comp/src/gb.gui.base/.src/IconView/_IconView_Item.class

@@ -357,7 +357,7 @@ Public Sub _Draw(hRect As Rect, hClip As Rect, hIconView As IconView, bHorizonta
       HT = hRect.H + DS \ 2
 
       If H > HT Then 
-        sText = Paint.TrimRichText(sText, W, HT)
+        sText = MyTrimRichText(sText, W, HT)
         $bEllipsized = True
       Else
         $bEllipsized = False
@@ -413,7 +413,7 @@ Public Sub _Draw(hRect As Rect, hClip As Rect, hIconView As IconView, bHorizonta
       HT = hRect.H - (Y - hRect.Y)
 
       If H > HT Then 
-        sText = Paint.TrimRichText(sText, hRect.W, HT)
+        sText = MyTrimRichText(sText, hRect.W, HT)
         $bEllipsized = True
       Else
         $bEllipsized = False
@@ -794,3 +794,26 @@ Private Sub Tag_Write(Value As Variant)
   $vTag = Value
 
 End
+
+Private Sub MyTrimRichText(RichText As String, W As Float, Optional H As Float) As String
+
+  Dim sResult As String
+  Dim cCache As Collection
+  
+  cCache = GetIconView()._GetTrimTextCache()
+  sResult = cCache[RichText]
+  If Not sResult Then
+    sResult = Paint.TrimRichText(RichText, W, H)
+    cCache[RichText] = sResult
+    If cCache.Count > 256 Then 
+      For Each cCache
+        cCache.Remove(cCache.Key)
+        Break
+      Next
+    Endif
+  Endif
+  
+  Return sResult
+  
+End
+

comp/src/gb.gui.base/.src/Paint.class

@@ -167,7 +167,7 @@ Static Public Sub TrimRichText(RichText As String, W As Float, Optional H As Flo
     If bMarkup Then Continue
     sPrevLeft = sLeft
     sLeft = HtmlLeft(RichText, I)
-    If Paint.Font.RichTextHeight(sLeft, W) > H Then Break
+    If Paint.Font.RichTextHeight(AddThreeDots(sLeft), W) > H Then Break
   Next
   
   If I = 1 Then Return

comp/src/gb.gui.base/.src/Test/FTestIconView.form

@@ -25,5 +25,6 @@
     Sorted = True
     Editable = True
     GridSize = 24
+    IconLines = 3
   }
 }