#---------------------------------------------------------------------- # Name: wx.lib.resizewidget # Purpose: Adds a resize handle to any widget, with support for # notifying parents when layout needs done. # # Author: Robin Dunn # # Created: 12-June-2008 # Copyright: (c) 2008 by Total Control Software # Licence: wxWindows license #---------------------------------------------------------------------- """ Reparents a given widget into a specialized panel that provides a resize handle for the widget. When the user drags the resize handle the widget is resized accordingly, and an event is sent to notify parents that they should recalculate their layout. """ import wx import wx.lib.newevent #----------------------------------------------------------------------------- # dimensions used for the handle RW_THICKNESS = 4 RW_LENGTH = 12 # default colors for the handle RW_PEN = 'black' RW_FILL = '#A0A0A0' RW_FILL2 = '#E0E0E0' # An event and event binder that will notify the containers that they should # redo the layout in whatever way makes sense for their particular content. _RWLayoutNeededEvent, EVT_RW_LAYOUT_NEEDED = wx.lib.newevent.NewCommandEvent() # TODO: Add a style flag that indicates that the ResizeWidget should # try to adjust the layout itself by looking up the sizer and # containment hierachy. Maybe also a style that says that it is okay # to adjust the size of top-level windows too. #----------------------------------------------------------------------------- class ResizeWidget(wx.Panel): def __init__(self, *args, **kw): wx.Panel.__init__(self, *args, **kw) self._init() self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown) self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp) self.Bind(wx.EVT_MOTION, self.OnMouseMove) self.Bind(wx.EVT_LEAVE_WINDOW, self.OnMouseLeave) self.Bind(wx.EVT_SIZE, self.OnSize) self.Bind(wx.EVT_PAINT, self.OnPaint) def _init(self): self._managedChild = None self._bestSize = wx.Size(100, 25) self.InvalidateBestSize() self._resizeCursor = False self._dragPos = None self._resizeEnabled = True self._reparenting = False self.SetDimensions() self.SetColors() def SetDimensions(self, thickness=RW_THICKNESS, length=RW_LENGTH): self.RW_THICKNESS = thickness self.RW_LENGTH = length def SetColors(self, pen=RW_PEN, fill=RW_FILL, fill2=RW_FILL2): self.RW_PEN = pen self.RW_FILL = fill self.RW_FILL2 = fill2 def SetManagedChild(self, child): self._reparenting = True child.Reparent(self) # This calls AddChild, so do the rest of the init there self._reparenting = False self.AdjustToChild() def GetManagedChild(self): return self._managedChild ManagedChild = property(GetManagedChild, SetManagedChild) def AdjustToChild(self): self.AdjustToSize(self._managedChild.GetEffectiveMinSize()) def AdjustToSize(self, size): size = wx.Size(*size) self._bestSize = size + (self.RW_THICKNESS, self.RW_THICKNESS) self.InvalidateBestSize() self.SetSize(self._bestSize) def EnableResize(self, enable=True): self._resizeEnabled = enable self.Refresh(False) def IsResizeEnabled(self): return self._resizeEnabled #=== Event handler methods === def OnLeftDown(self, evt): if self._hitTest(evt.GetPosition()) and self._resizeEnabled: self.CaptureMouse() self._dragPos = evt.GetPosition() def OnLeftUp(self, evt): if self.HasCapture(): self.ReleaseMouse() self._dragPos = None def OnMouseMove(self, evt): # set or reset the drag cursor pos = evt.GetPosition() if self._hitTest(pos) and self._resizeEnabled: if not self._resizeCursor: self.SetCursor(wx.Cursor(wx.CURSOR_SIZENWSE)) self._resizeCursor = True else: if self._resizeCursor: self.SetCursor(wx.Cursor(wx.CURSOR_ARROW)) self._resizeCursor = False # determine if a new size is needed if evt.Dragging() and self._dragPos is not None: delta = self._dragPos - pos newSize = self.GetSize() - delta.Get() self._adjustNewSize(newSize) if newSize != self.GetSize(): self.SetSize(newSize) self._dragPos = pos self._bestSize = newSize self.InvalidateBestSize() self._sendEvent() def _sendEvent(self): event = _RWLayoutNeededEvent(self.GetId()) event.SetEventObject(self) self.GetEventHandler().ProcessEvent(event) def _adjustNewSize(self, newSize): if newSize.width < self.RW_LENGTH: newSize.width = self.RW_LENGTH if newSize.height < self.RW_LENGTH: newSize.height = self.RW_LENGTH if self._managedChild: minsize = self._managedChild.GetMinSize() if minsize.width != -1 and newSize.width - self.RW_THICKNESS < minsize.width: newSize.width = minsize.width + self.RW_THICKNESS if minsize.height != -1 and newSize.height - self.RW_THICKNESS < minsize.height: newSize.height = minsize.height + self.RW_THICKNESS maxsize = self._managedChild.GetMaxSize() if maxsize.width != -1 and newSize.width - self.RW_THICKNESS > maxsize.width: newSize.width = maxsize.width + self.RW_THICKNESS if maxsize.height != -1 and newSize.height - self.RW_THICKNESS > maxsize.height: newSize.height = maxsize.height + self.RW_THICKNESS def OnMouseLeave(self, evt): if self._resizeCursor: self.SetCursor(wx.Cursor(wx.CURSOR_ARROW)) self._resizeCursor = False def OnSize(self, evt): if not self._managedChild: return sz = self.GetSize() cr = wx.Rect((0, 0), sz - (self.RW_THICKNESS, self.RW_THICKNESS)) self._managedChild.SetRect(cr) r1 = wx.Rect(0, cr.height, sz.width, self.RW_THICKNESS) r2 = wx.Rect(cr.width, 0, self.RW_THICKNESS, sz.height) self.RefreshRect(r1) self.RefreshRect(r2) def OnPaint(self, evt): # draw the resize handle dc = wx.PaintDC(self) w, h = self.GetSize() points = [ (w - 1, h - self.RW_LENGTH), (w - self.RW_THICKNESS, h - self.RW_LENGTH), (w - self.RW_THICKNESS, h - self.RW_THICKNESS), (w - self.RW_LENGTH, h - self.RW_THICKNESS), (w - self.RW_LENGTH, h - 1), (w - 1, h - 1), (w - 1, h - self.RW_LENGTH), ] dc.SetPen(wx.Pen(self.RW_PEN, 1)) if self._resizeEnabled: fill = self.RW_FILL else: fill = self.RW_FILL2 dc.SetBrush(wx.Brush(fill)) dc.DrawPolygon(points) def _hitTest(self, pos): # is the position in the area to be used for the resize handle? w, h = self.GetSize() if ( w - self.RW_THICKNESS <= pos.x <= w and h - self.RW_LENGTH <= pos.y <= h ): return True if ( w - self.RW_LENGTH <= pos.x <= w and h - self.RW_THICKNESS <= pos.y <= h ): return True return False #=== Overriden virtuals from the base class === def AddChild(self, child): assert self._managedChild is None, "Already managing a child widget, can only do one" self._managedChild = child wx.Panel.AddChild(self, child) # This little hack is needed because if this AddChild was called when # the widget was first created, then the OOR values will get reset # after this function call, and so the Python proxy object saved in # the window may be different than the child object we have now, so we # need to reset which proxy object we're using. Look for it by ID. def _doAfterAddChild(self, id): if not self: return child = self.FindWindowById(id) self._managedChild = child self.AdjustToChild() self._sendEvent() if self._reparenting: _doAfterAddChild(self, child.GetId()) else: wx.CallAfter(_doAfterAddChild, self, child.GetId()) def RemoveChild(self, child): self._init() wx.Panel.RemoveChild(self, child) def DoGetBestSize(self): return self._bestSize #-----------------------------------------------------------------------------