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60 lines
1.7 KiB
Lua
60 lines
1.7 KiB
Lua
--[[--
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AlphaContainer will paint its content (a single widget) at the specified opacity level (0..1)
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Example:
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local alpha
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alpha = AlphaContainer:new{
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alpha = 0.7,
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FrameContainer:new{
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background = Blitbuffer.COLOR_WHITE,
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bordersize = Size.border.default,
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margin = 0,
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padding = Size.padding.default
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}
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}
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--]]
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local Blitbuffer = require("ffi/blitbuffer")
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local WidgetContainer = require("ui/widget/container/widgetcontainer")
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local AlphaContainer = WidgetContainer:new{
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alpha = 1,
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-- we cache a blitbuffer object for re-use here:
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private_bb = nil,
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}
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function AlphaContainer:paintTo(bb, x, y)
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local contentSize = self[1]:getSize()
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if not self.private_bb
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or self.private_bb:getWidth() ~= contentSize.w
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or self.private_bb:getHeight() ~= contentSize.h
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then
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if self.private_bb then
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self.private_bb:free() -- free the one we're going to replace
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end
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-- create a private blitbuffer for our child widget to paint to
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self.private_bb = Blitbuffer.new(contentSize.w, contentSize.h, bb:getType())
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-- fill it with our usual background color
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self.private_bb:fill(Blitbuffer.COLOR_WHITE)
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end
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-- now, compose our child widget's content on our private blitbuffer canvas
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self[1]:paintTo(self.private_bb, 0, 0)
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-- and finally blit the private blitbuffer to the target blitbuffer at the requested opacity level
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bb:addblitFrom(self.private_bb, x, y, 0, 0, contentSize.w, contentSize.h, self.alpha)
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end
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function AlphaContainer:onCloseWidget()
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if self.private_bb then
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self.private_bb:free()
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self.private_bb = nil
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end
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end
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return AlphaContainer
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