I needed a control which had visual aspects of both an activity indicator as well as an annunciator. Not finding one, I decided to build one to statisfy that need by providing textual, color, and animated feedback to the user.
The control uses Quartz 2D and Core Animation to provide a reasonable level of performance with virtually no CPU overhead required for the animation. The number of segments, segment color, segment thickness, rotation rate, and text can all be customized.
If you find this control of use (or find bugs), I'd love to hear from you! Drop a note to firstname.lastname@example.org with questions, comments, or dissenting opinions.
Adding this control to your XCode project is straightforward:
- Add the F3Swirly.h and F3Swirly.m files to your project
- Add a new blank subview to the nib, sized and positioned to match what the bar gauge should look like.
- In the properties inspector for this subview, change the class to "F3Swirly"
- Add an outlet to represent the control
- Add thresholds to describe the color, number of segments, textual label, etc. as needed. See the demo code for an example of how this is done.
- Update your code to set the value property as appropriate.
- Specifying a negative integer for rotation rate will result in counter-clockwise rotation, while positive integers will result in clockwise rotation.
- Specifying zero for the number of segments will result in only the label being shown.
- Specifying nil for the label for a specific threshold will result in no text being shown.
Copyright (c) 2012 by Brad Benson All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
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