RMShapedImageView - Swift
Swift version of the UIImageView
subclass that ignores touches on transparent pixels, based on OBShapedButton by Ole Begemann.
RMShapedImageView
does it magic by overriding pointInside:withEvent:
. This method is called to determine if a touch is inside the view. In our case, we only want to return true
if the corresponding pixels are not transparent (alpha > 0
).
Usage
- Open the XCode Project.
- Drag in RMShapedImageView.framework into your project.
- Replace your
UIImageView
withRMShapedImageView
either in code or Interface Builder (by setting the Class of yourUIImageView
toRMShapedImageView
). Note: If done in IB, be sure to set the Module field as well toRMShapedImageView
. - Profit!
Configuration
Touches are inexact things and querying the alpha value of a single pixel might be too strict, even more so if the image is scaled down. Furthermore, if the image has shadows you might also want to ignore touches on them. RMShapedImageView
has two configuration options to work around these problems:
shapedTransparentMaxAlpha
: maximum alpha value that will be considered transparent. 0 by default.shapedPixelTolerance
: number of pixels around the point that will be examined. If at least one of them has alpha bigger thanshapedTransparentMaxAlpha
pointInside:withEvent:
will returntrue
. 0 by default.
License
Copyright 2013 Robot Media SL
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.