Android color picker - updating color array
I'm trying to create a color picker for Android that looks like a minimalist开发者_运维知识库ic version of Gimp's. So, it has a hue slider and a rectangle with saturation/value variants of a color chosen in hue slider.
Question: what is the best way to create the rectangle?
Right now, I'm creating an 200x200 array of pixels, but it takes ~5sec to create and display rectangle with that array. And I need colors in rectangle to change whenever I change the value in hue slider...
Rectangle is bitmap, btw. Can I use color matrices on that and how? Any examples?
Thanks in advance!
You can create the rectangle with saturation/value variants that change according to the selected hue, by drawing the rectangle with LinearGradients.
You can incorporate the code here: http://code.google.com/p/android-color-picker/ into your application. Seems that this is what you want.
OpenIntents has a very nice color picker you can use. It can be installed as an independent app and launched with Intents.
- Code: http://code.google.com/p/openintents/source/browse/#svn/trunk/ColorPicker
- Screenshots/download: http://www.openintents.org/en/colorpicker
- Intent specification: http://www.openintents.org/en/node/670
One possibility is to pre-create the rectangles on your developer PC for each slider position, embed them as resources, and then swap in the right one when the slider changes. This may make for a portly application, but it will be nice and quick.
I have not dealt with the 2D graphics API much, so I don't know if there are other possibilities (e.g., color matrices).
Can this be applied to an image color picker as well?
Use case:
- Select a particular pixel on an image.
- The pixel selected generates a color on a rectangle shape.
- Perhaps generating color codes for the pixel selected?
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