Drop Shadow behind ui.view()
How would I only draw the visible part of the shadow?
Anyone? When @JonB says
you could only draw the visible part of the shadow (two thin rectangles) rather than the whole thing
How do I accomplish this?
Webmaster4o, I am not really sure. But if you make 2 rects only the width you want to draw in ( path seems to be accumulative) Also there is a path.line_to. Sorry, only guessing and trying to give some ideas. I tried to do it in code, but I am not good enough at the moment
Ok, thanks, I'll try.
Ok, I found a solution! Here's my class:
class shadowview(ui.View): '''A class for a ui.View that has a shadow behind it. This is accomplished by: 1. Draw the background 2. Redraw with a shadow, but set clipping so only the edge of the shadow shows. This prevents the part of the shadow that's under the background from showing. ''' def draw(self): '1' #Setup path of window shape path = ui.Path.rect(0, 0, self.width-10, self.height-10) #Draw background ui.set_color((0.95,0.95,0.95,0.5)) path.fill() '2' #Setup mask by creating image from PIL import ImageDraw i = Image.new('RGBA',(520,290), (255,255,255,0)) draw = ImageDraw.Draw(i) draw.rectangle((self.width-10, 0, self.width, self.height),fill=(0,0,0,255)) draw.rectangle((0, self.height-10, self.width, self.height),fill=(0,0,0,255)) #Convert to UI, apply the mask, and draw shadow! i = pil_to_ui(i) i.clip_to_mask() ui.set_color((1,1,1,1)) ui.set_shadow("black",-2,-2,10) path.fill()
It fixes the problem of opacity by drawing the shadow rectangle with clipping set so only the shadow is drawn.
Before, I got something like this when I tried to draw with a transparent background:
This was because you could see the shadow behind the view.
Now, I have something like this:
Because only part of the shadow is drawn.
blmacbeth last edited by blmacbeth
I have been playing around with
objc_utilagain and came up with this piece of code you might find applicable to your code above:
# coding: utf-8 from objc_util import * import ui UIColor = ObjCClass('UIColor') view = ui.View(frame=(0,0,500,500)) box = ui.View(frame=(0,0,100,100)) view.background_color = 'white' box.background_color = 'red' box.center = view.center view.add_subview(box) box_pntr = ObjCInstance(box) ## Note: this allows for shadows to be drawn box_pntr.layer().setMasksToBounds_(False) box_pntr.layer().setCornerRadius_(6) ## Note: CGColor is needed in order for this to work box_pntr.layer().setBorderColor_(UIColor.cyanColor().CGColor()) box_pntr.layer().setBorderWidth_(3) box_pntr.layer().setShadowRadius_(10) box_pntr.layer().setShadowOffset_(CGSize(0,0)) box_pntr.layer().setShadowOpacity_(1.0) view.present('sheet')
Hope you find this useful.
@blmacbeth , thanks for sharing. Even though I wasn't the one asking for it, I have saved it for use later 😜
@blmacbeth, I am just playing around with ui.TableView.datat_source at the moment. But I just remembered your code for shadowing a view. I wanted to try it. I did, I cut it up just to return a ui.View. But the full script below (nothing complete about the script, still working on it. Just excited and wanted to share) . But It looks nice.
But it would be so much more useful if you created a custom class based on ui.View, and tweak the settings etc... This could be a very cool class to submit to the pythonistia_tools repo.
But thanks again. I don't play with objc stuff for now... Still trying to learn python.
# coding: utf-8 import ui from objc_util import * def shadow_box(parent): # using chopped up code from @blmacbeth UIColor = ObjCClass('UIColor') f = ui.Rect(*parent.bounds).inset(10,10) box = ui.View(frame=f) box.background_color = 'white' box_pntr = ObjCInstance(box) ## Note: this allows for shadows to be drawn box_pntr.layer().setMasksToBounds_(False) box_pntr.layer().setCornerRadius_(6) ## Note: CGColor is needed in order for this to work box_pntr.layer().setBorderColor_(UIColor.grayColor().CGColor()) box_pntr.layer().setBorderWidth_(.5) box_pntr.layer().setShadowRadius_(10) box_pntr.layer().setShadowOffset_(CGSize(0,0)) box_pntr.layer().setShadowOpacity_(1.0) return box class AbstractDataSource(object): def __init__(self, tbl, items, **kwargs): # assign positional args tbl.data_source = self tbl.data_source.items = items self.sections = None self.can_move = False self.can_delete = False self.can_edit = False self.make_cell_func = None self.cell_type = '' self.sec_title = None for k,v in kwargs.iteritems(): if hasattr(self, k): setattr(self, k, v) def tableview_number_of_rows(self, tv, sec): # Return the number of rows in the section return len(tbl.data_source.items) def tableview_cell_for_row(self, tv, sec, row): # Create and return a cell for the given section/row if self.make_cell_func: return self.make_cell_func(tv, sec, row) cell = ui.TableViewCell(self.cell_type) cell.text_label.text = 'Foo Bar' return cell def tableview_title_for_header(self, tv, sec): # Return a title for the given section. # If this is not implemented, no section headers will be shown. if self.sec_title: return self.sec_title elif not self.sections: return None else: return 'Some Section' def tableview_can_delete(self, tv, sec, row): # Return True if the user should be able to delete the given row. return True def tableview_can_move(self, tv, sec, row): # Return True if a reordering control should be shown for the given row (in editing mode). return True def tableview_delete(self, tv, sec, row): # Called when the user confirms deletion of the given row. pass def tableview_move_row(self, tv, from_sec, from_row, to_sec, to_row): # Called when the user moves a row with the reordering control (in editing mode). pass class MyListDataSource(AbstractDataSource): def __init__(self, tbl, items, **kwargs): AbstractDataSource.__init__(self, tbl, items , **kwargs) # we do this instead of overriding, to get extended functionality.. self.make_cell_func = self.make_cell def make_cell(self, tv, sec, row): cell = ui.TableViewCell(self.cell_type) cell.text_label.text = 'make_cell - row' + str(row) return cell if __name__ == '__main__': f = (0,0,500, 500) v = ui.View(frame = f, bg_color = 'white') tbl = ui.TableView() box = shadow_box(v) v.add_subview(box) ds = MyListDataSource(tbl, range(20), sec_title = 'ian 👿') box.add_subview(tbl) v.present('sheet') r = ui.Rect(*tbl.superview.bounds).inset(10,10) tbl.frame = r```
Ask and he shall receive. It's not perfect, yet. There are some clipping problems I can't figure out.
# coding: utf-8 from objc_util import * import ui UIColor = ObjCClass('UIColor') def Color(red=0, green=0, blue=0, alpha=1): return UIColor.colorWithRed_green_blue_alpha_(red, green, blue, alpha) class ShadowView (ui.View): def __init__(self, *args, **kwargs): super(ShadowView, self).__init__() self.pntr = ObjCInstance(self) self.pntr.layer().setMasksToBounds_(False) ## Go ahead and do this. @property def corner_radius(self): return self.pntr.layer().cornerRadius() @corner_radius.setter def corner_radius(self, val): self.pntr.layer().setCornerRadius_(val) @property def border_color(self): return self.pntr.layer().borderColor() @border_color.setter def border_color(self, color): self.pntr.layer().setBorderColor_(Color(*color).CGColor()) @property def border_width(self): return self.pntr.layer().borderWidth() @border_width.setter def border_width(self, val): self.pntr.layer().setBorderWidth_(val) @property def opacity(self): return self.pntr.layer().opacity() @opacity.setter def opacity(self, val): self.pntr.layer().setOpacity_(value) @property def hidden(swlf): return self.pntr.layer().hidden() @hidden.setter def hidden(self, val): self.pntr.layer().setHidden_(val) @property def masks_to_bounds(self): return self.pntr.layer().masksToBounds() @masks_to_bounds.setter def masks_to_bounds(self, val): self.pntr.layer().setMasksToBounds_(val) @property def mask(self): return self.pntr.layer().mask() @mask.setter def mask(self, new_mask): self.pntr.layer().setMask_(new_mask) @property def double_sided(self): return self.pntr.layer().doubleSided() @double_sided.setter def double_sided(self, val): self.pntr.layer().setDoubleSided_(val) @property def shadow_opacity(self): return self.pntr.layer().shadowOpacity() @shadow_opacity.setter def shadow_opacity(self, val): self.pntr.layer().setShadowOpacity_(val) @property def shadow_radius(self): return self.pntr.layer().shadowRadius() @shadow_radius.setter def shadow_radius(self, val): self.pntr.layer().setShadowRadius_(val) @property def shadow_offset(self): return self.pntr.layer().shadowOffset() @shadow_offset.setter def shadow_offset(self, offset): ## offset should be a tuple, but I'll take a CGSize if isinstance(offset, CGSize): self.pntr.layer().setShadowOffset_(offset) elif isinstance(offset, tuple): self.pntr.layer().setShadowOffset_(CGSize(*offset)) else: raise TypeError("Cannot use type %s. Use CGSize or tuple" % type(offset)) @property def shadow_color(self): return self.pntr.layer().shadowColor() @shadow_color.setter def shadow_color(self, color): if isinstance(color, UIColor.CGColor()): self.pntr.layer().setShadowColor_(color) elif isinstance(color, tuple) and len(color) == 4: self.pntr.layer().setShadowColor_(Color(*color).CGColor()) else: raise ValueError('Cannot use type %s. Use UIColor or tuple' % type(color)) @property def shadow_path(self): return self.pntr.layer().shadowPath() @shadow_path.setter def shadow_path(self, path): self.pntr.layer().setShadowPath_(path) @property def style(self): return self.pntr.layer().style() @style.setter def style(self, style): self.pntr.layer().setStyle_(style) if __name__ == '__main__': view = ui.View(frame=(0,0,500,500)) box = ShadowView(frame=(0,0,100,100)) view.background_color = 'white' box.background_color = 'red' box.center = view.center view.add_subview(box) box.masks_to_bounds = False box.corner_radius = 6. box.border_color = (0,1,0) box.border_width = 6 box.shadow_radius = 10 box.shadow_offset = (0,0) box.shadow_opacity = 1 view.present('sheet')
I tested most of it, but there may still be some funny-ness.
@blmacbeth , ok thanks. I will try it. Maybe I am wrong, but doesn't your call to super need to be like
super(ShadowView, self).init(self, *args, **kwargs)
If not, then I would love to know why not.
dgelessus last edited by
@Phuket2 Since you've already passed
selfas an argument to
super, you already get (bound) methods instead of normal functions, so you don't need to pass
selfas the first parameter to
__init__. Though you are right, the
**kwargsdo need to be passed (if you want
ui.Viewto interpret them, which I assume is the case). For
ui.Viewthe docs say that you don't need to call
super().__init__()at all, perhaps everything important is already handled by
@Phuket2 Ha! You caught me. That may be a problem… it should look like:
super(ShadowView, self).__init__(*args, **kwargs)
I must have been in a zone to miss that. There is no need to repeat
super(ShadowView, self)returns an instance of the superclass, which will pass
@dgelessus , thanks. I tend not to call super anymore. I normally call the class init method. I think I did that because I was doing multiple inheritance and was having a hard time following what was going on 😭, to this day I still don't know the most correct way.
I am pretty sure I have checked this theory of not having to pass on params to ui.View, I know it's in the docs. As far as I can see it does not work. Maybe if you have no init. Not sure that should cancel new, but maybe it's been written to work that way. So many combinations, I get confused 😱
@blmacbeth , lol. I understand. I thought you had some special trick up your sleeve 😝
@Phuket2 I wish I have a cool trick up my sleeve! But to comment on your response about not calling
super: it is best practice to call
superwhen subclassing. This is because it allows you to refactor your code with less changes made afterwards.
For example: let's say I someday make a kick-ass version of
ui.Viewlook like children's toys. So, you want to incorporate the new view classes into your old code. The way you have, you would need to change every instance of
ui.View.__init__(...). By calling
superyou no longer have to do all that tedious work. It makes life slightly easier.
I'm not saying that what your doing is wrong; I have plenty of classes that do the same thing. But o have started using
superbecause of the refactoring issue.
Now, this could all be a load of bullshit I am feeding you, so go look it up yourself and let me know if I'm correct! 😛
@blmacbeth , hmmm, I am a little on the drunk side now 🎉😎 almost 11:30pm here now. So maybe I should wait until tomorrow to look it up 😱
But I started getting a problem when inheriting from multiple classes. Gets confusing about which base class is being called ( it did for me anyway). That's when I started using the implicit calls to base class's init methods instead. But I see your point though. I haven't managed to write anything significant enough in Python were it's been a problem to refactor 😭
Still trying though
JonB last edited by
re needing to call View.init, see
If you do not implement your own init, you do not need to call super init.
If you have an init, you do need to call the View.init
dgelessus last edited by
From what I've heard, you need to use
super()for some aspects of multiple inheritance to work properly. I know almost nothing about the details of multiple inheritance on Python though, so I can't tell you why exactly that is and what would break otherwise. Mostly because multiple inheritance is not needed very often.