import wx import images #---------------------------------------------------------------------- class DragShape: def __init__(self, bmp): self.bmp = bmp self.pos = (0,0) self.shown = True self.text = None self.fullscreen = False def HitTest(self, pt): rect = self.GetRect() return rect.InsideXY(pt.x, pt.y) def GetRect(self): return wx.Rect(self.pos[0], self.pos[1], self.bmp.GetWidth(), self.bmp.GetHeight()) def Draw(self, dc, op = wx.COPY): if self.bmp.Ok(): memDC = wx.MemoryDC() memDC.SelectObject(self.bmp) dc.Blit(self.pos[0], self.pos[1], self.bmp.GetWidth(), self.bmp.GetHeight(), memDC, 0, 0, op, True) return True else: return False #---------------------------------------------------------------------- class DragCanvas(wx.ScrolledWindow): def __init__(self, parent, ID): wx.ScrolledWindow.__init__(self, parent, ID) self.shapes = [] self.dragImage = None self.dragShape = None self.hiliteShape = None self.SetCursor(wx.StockCursor(wx.CURSOR_ARROW)) self.bg_bmp = images.getBackgroundBitmap() self.SetBackgroundStyle(wx.BG_STYLE_CUSTOM) # Make a shape from an image and mask. This one will demo # dragging outside the window bmp = images.getTestStarBitmap() #bmp = wx.Bitmap('bitmaps/toucan.png') shape = DragShape(bmp) shape.pos = (5, 5) shape.fullscreen = True self.shapes.append(shape) # Make a shape from some text text = "Some Text" bg_colour = wx.Colour(57, 115, 57) # matches the bg image font = wx.Font(15, wx.ROMAN, wx.NORMAL, wx.BOLD) textExtent = self.GetFullTextExtent(text, font) # create a bitmap the same size as our text bmp = wx.EmptyBitmap(textExtent[0], textExtent[1]) # 'draw' the text onto the bitmap dc = wx.MemoryDC() dc.SelectObject(bmp) dc.SetBackground(wx.Brush(bg_colour, wx.SOLID)) dc.Clear() dc.SetTextForeground(wx.RED) dc.SetFont(font) dc.DrawText(text, 0, 0) dc.SelectObject(wx.NullBitmap) mask = wx.Mask(bmp, bg_colour) bmp.SetMask(mask) shape = DragShape(bmp) shape.pos = (5, 100) shape.text = "Some dragging text" self.shapes.append(shape) bmp = images.getTheKidBitmap() shape = DragShape(bmp) shape.pos = (200, 5) self.shapes.append(shape) self.Bind(wx.EVT_ERASE_BACKGROUND, self.OnEraseBackground) self.Bind(wx.EVT_PAINT, self.OnPaint) self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown) self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp) self.Bind(wx.EVT_MOTION, self.OnMotion) self.Bind(wx.EVT_LEAVE_WINDOW, self.OnLeaveWindow) # We're not doing anything here, but you might have reason to. # for example, if you were dragging something, you might elect to # 'drop it' when the cursor left the window. def OnLeaveWindow(self, evt): pass # tile the background bitmap def TileBackground(self, dc): sz = self.GetClientSize() w = self.bg_bmp.GetWidth() h = self.bg_bmp.GetHeight() x = 0 while x < sz.width: y = 0 while y < sz.height: dc.DrawBitmap(self.bg_bmp, x, y) y = y + h x = x + w # Go through our list of shapes and draw them in whatever place they are. def DrawShapes(self, dc): for shape in self.shapes: if shape.shown: shape.Draw(dc) # This is actually a sophisticated 'hit test', but in this # case we're also determining which shape, if any, was 'hit'. def FindShape(self, pt): for shape in self.shapes: if shape.HitTest(pt): return shape return None # Remove a shape from the display def EraseShape(self, shape, dc): r = shape.GetRect() dc.SetClippingRect(r) self.TileBackground(dc) self.DrawShapes(dc) dc.DestroyClippingRegion() # Clears the background, then redraws it. If the DC is passed, then # we only do so in the area so designated. Otherwise, it's the whole thing. def OnEraseBackground(self, evt): dc = evt.GetDC() if not dc: dc = wx.ClientDC(self) rect = self.GetUpdateRegion().GetBox() dc.SetClippingRect(rect) self.TileBackground(dc) # Fired whenever a paint event occurs def OnPaint(self, evt): dc = wx.PaintDC(self) self.PrepareDC(dc) self.DrawShapes(dc) # Left mouse button is down. def OnLeftDown(self, evt): # Did the mouse go down on one of our shapes? shape = self.FindShape(evt.GetPosition()) # If a shape was 'hit', then set that as the shape we're going to # drag around. Get our start position. Dragging has not yet started. # That will happen once the mouse moves, OR the mouse is released. if shape: self.dragShape = shape self.dragStartPos = evt.GetPosition() # Left mouse button up. def OnLeftUp(self, evt): if not self.dragImage or not self.dragShape: self.dragImage = None self.dragShape = None return # Hide the image, end dragging, and nuke out the drag image. self.dragImage.Hide() self.dragImage.EndDrag() self.dragImage = None if self.hiliteShape: self.RefreshRect(self.hiliteShape.GetRect()) self.hiliteShape = None # reposition and draw the shape # Note by jmg 11/28/03 # Here's the original: # # self.dragShape.pos = self.dragShape.pos + evt.GetPosition() - self.dragStartPos # # So if there are any problems associated with this, use that as # a starting place in your investigation. I've tried to simulate the # wx.Point __add__ method here -- it won't work for tuples as we # have now from the various methods # # There must be a better way to do this :-) # self.dragShape.pos = ( self.dragShape.pos[0] + evt.GetPosition()[0] - self.dragStartPos[0], self.dragShape.pos[1] + evt.GetPosition()[1] - self.dragStartPos[1] ) self.dragShape.shown = True self.RefreshRect(self.dragShape.GetRect()) self.dragShape = None # The mouse is moving def OnMotion(self, evt): # Ignore mouse movement if we're not dragging. if not self.dragShape or not evt.Dragging() or not evt.LeftIsDown(): return # if we have a shape, but haven't started dragging yet if self.dragShape and not self.dragImage: # only start the drag after having moved a couple pixels tolerance = 2 pt = evt.GetPosition() dx = abs(pt.x - self.dragStartPos.x) dy = abs(pt.y - self.dragStartPos.y) if dx <= tolerance and dy <= tolerance: return # erase the shape since it will be drawn independently now dc = wx.ClientDC(self) self.dragShape.shown = False self.EraseShape(self.dragShape, dc) if self.dragShape.text: self.dragImage = wx.DragString(self.dragShape.text, wx.StockCursor(wx.CURSOR_HAND)) else: self.dragImage = wx.DragImage(self.dragShape.bmp, wx.StockCursor(wx.CURSOR_HAND)) hotspot = self.dragStartPos - self.dragShape.pos self.dragImage.BeginDrag(hotspot, self, self.dragShape.fullscreen) self.dragImage.Move(pt) self.dragImage.Show() # if we have shape and image then move it, posibly highlighting another shape. elif self.dragShape and self.dragImage: onShape = self.FindShape(evt.GetPosition()) unhiliteOld = False hiliteNew = False # figure out what to hilite and what to unhilite if self.hiliteShape: if onShape is None or self.hiliteShape is not onShape: unhiliteOld = True if onShape and onShape is not self.hiliteShape and onShape.shown: hiliteNew = True # if needed, hide the drag image so we can update the window if unhiliteOld or hiliteNew: self.dragImage.Hide() if unhiliteOld: dc = wx.ClientDC(self) self.hiliteShape.Draw(dc) self.hiliteShape = None if hiliteNew: dc = wx.ClientDC(self) self.hiliteShape = onShape self.hiliteShape.Draw(dc, wx.INVERT) # now move it and show it again if needed self.dragImage.Move(evt.GetPosition()) if unhiliteOld or hiliteNew: self.dragImage.Show() #---------------------------------------------------------------------- def runTest(frame, nb, log): win = wx.Panel(nb, -1) canvas = DragCanvas(win, -1) def onSize(evt, panel=win, canvas=canvas): canvas.SetSize(panel.GetSize()) win.Bind(wx.EVT_SIZE, onSize) return win #---------------------------------------------------------------------- overview = """\ DragImage is used when you wish to drag an object on the screen, and a simple cursor is not enough. On Windows, the WIN32 API is used to do achieve smooth dragging. On other platforms, GenericDragImage is used. Applications may also prefer to use GenericDragImage on Windows, too. wxPython note: wxPython uses GenericDragImage on all platforms, but uses the DragImage name. To use this class, when you wish to start dragging an image, create a DragImage object and store it somewhere you can access it as the drag progresses. Call BeginDrag to start, and EndDrag to stop the drag. To move the image, initially call Show and then Move. If you wish to update the screen contents during the drag (for example, highlight an item as in the example), first call Hide, update the screen, call Move, and then call Show. You can drag within one window, or you can use full-screen dragging either across the whole screen, or just restricted to one area of the screen to save resources. If you want the user to drag between two windows, then you will need to use full-screen dragging. """ if __name__ == '__main__': import sys,os import run run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])