fix: memory leak

optimize: use special ChangableChild object

readme.md

@@ -297,7 +297,7 @@ Built-in interpolation modifiers:
 ```nim
 type
   MyComponent = ref object of Uiobj
-    changableChild: CustomProperty[UiRect]
+    changableChild: ChangableChild[UiRect]
 
 registerComponent MyComponent
 
@@ -324,7 +324,7 @@ Changable childs could be used to re-build component tree on any event.
 # ...in makeLaout macro...
 
 var elements = ["first", "second"]
-var elementsObj: CustomProperty[Layout]
+var elementsObj: ChangableChild[Layout]
 
 elementsObj --- Layout():
   orientation = vertical
@@ -355,7 +355,7 @@ elementsObj --- Layout():
 The `<--- ctor: prop[]; event[]; ...` syntax can be used to re-build tree based on property changes
 ```nim
 var elements = ["first", "second"].property
-var elementsObj: CustomProperty[Layout]
+var elementsObj: ChangableChild[Layout]
 
 elementsObj --- Layout():
   <--- Layout(): elements[]

src/sigui/events.nim

@@ -16,9 +16,12 @@ type
   EventBase = object
     connected: seq[EventConnection[int]]  # type of function argument does not matter for this
 
+  FlaggedPointer* = distinct pointer
+    ## pointer, but first bit is used for a flag (pointers are aligned anyway)
+
   Event*[T] = object  # pointer is wrapped to an object to attach custom destructor
     p: ptr EventObj[T]
-    uiobj*: pointer  # most of events is .changed properties, after most of which redraw should happen. If not nil, emit will call redrawUiobj
+    uiobj*: FlaggedPointer  # most of events is .changed properties, after most of which redraw should happen. If not nil, emit will call redrawUiobj
 
   EventObj*[T] = object
     ## only EventHandler can be connected to event
@@ -29,7 +32,10 @@ type
     connected: seq[EventConnection[T]]
 
 
-var redrawUiobj*: proc(uiobj: pointer) {.cdecl.}
+var redrawUiobj*: proc(uiobj: FlaggedPointer) {.cdecl.}
+
+
+proc `==`*(a, b: FlaggedPointer): bool {.borrow.}
 
 
 #* ------------- Event ------------- *#
@@ -38,6 +44,17 @@ proc destroyEvent(s: ptr EventBase) {.raises: [].}
 proc destroyEventHandler(handler: ptr EventHandlerObj) {.raises: [].}
 
 
+proc `=trace`[T](event: var Event[T], env: pointer) =
+  if event.p != nil:
+    for conn in event.p[].connected.mitems:
+      `=trace`(conn, env)
+
+proc `=trace`(eh: var EventHandler, env: pointer) =
+  if eh.p != nil:
+    for event in eh.p[].connected:
+      `=trace`(event[], env)
+
+
 proc `=destroy`[T](s: Event[T]) =
   if s.p != nil:
     destroyEvent(cast[ptr EventBase](s.p))
@@ -64,6 +81,7 @@ proc destroyEvent(s: ptr EventBase) =
         handler[].connected.delete i
       else:
         inc i
+  `=destroy`(s[])
   dealloc s
 
 
@@ -86,6 +104,7 @@ proc destroyEventHandler(handler: ptr EventHandlerObj) =
         s[].connected.delete i
       else:
         inc i
+  `=destroy`(handler[])
   dealloc handler
 
 
@@ -154,7 +173,7 @@ proc emit*[T](s: Event[T], v: T, disableFlags: set[EventConnectionFlag] = {}) =
       if (disableFlags * s.p[].connected[i].flags).len == 0:
         s.p[].connected[i].f(v)
       inc i
-  if s.uiobj != nil:
+  if s.uiobj.pointer != nil:
     redrawUiobj s.uiobj
 
 proc emit*(s: Event[void], disableFlags: set[EventConnectionFlag] = {}) =
@@ -164,7 +183,7 @@ proc emit*(s: Event[void], disableFlags: set[EventConnectionFlag] = {}) =
       if (disableFlags * s.p[].connected[i].flags).len == 0:
         s.p[].connected[i].f()
       inc i
-  if s.uiobj != nil:
+  if s.uiobj.pointer != nil:
     redrawUiobj s.uiobj
 
 

src/sigui/scrollArea.nim

@@ -43,7 +43,7 @@ type
       {ScrollAreaSetting.low..ScrollAreaSetting.high}
     ).property
 
-    verticalScrollbarObj*: CustomProperty[UiObj]
+    verticalScrollbarObj*: ChangableChild[UiObj]
       ## if changed, properties below can be attached by you to new object
     verticalScrollbarOpacity*: Property[float]
       ## has default animation
@@ -53,7 +53,7 @@ type
     verticalScrollBarLastShown*: Property[Time]
     verticalScrollBarHideDelay*: Property[Duration] = initDuration(milliseconds = 1000).property
 
-    horizontalScrollbarObj*: CustomProperty[UiObj]
+    horizontalScrollbarObj*: ChangableChild[UiObj]
       ## if changed, properties below can be attached by you to new object
     horizontalScrollbarOpacity*: Property[float]
       ## has default animation

src/sigui/textArea.nim

@@ -42,9 +42,9 @@ type
 
 
   TextArea* = ref object of Uiobj
-    cursorObj*: CustomProperty[UiObj]
-    selectionObj*: CustomProperty[Uiobj]
-    textObj*: CustomProperty[UiText]
+    cursorObj*: ChangableChild[UiObj]
+    selectionObj*: ChangableChild[Uiobj]
+    textObj*: ChangableChild[UiText]
 
     active*: Property[bool]
     text*: Property[string]