In my iPhone app, I require to recognize the gesture or motion made by the user on the view without touching it.
I want the hand free gestures to be recognized and perform a function on view.
I need that the image should move with the gesture detection.
What needs to be done?
How do I recognize it?
Any directions or tutorials will be really appreciated.
You might want to have a look at OpenCV. There is a good example on how to use OpenCV to recognize a hand here: http://www.andol.info/hci/1661.htm
Related
I got an app that allows users to add content to a canvas. I would like to be able to offer the user an ability to move, rotate, resize, reflect this content. Currently I'm doing this with gestures, but would like to know if there is some sort of open-source widget that draws a box around the view and adds 4 buttons to do these functions:
rotate 90 degrees
rotate freely
resize
delete
Can anyone think of an open source framework that I can add to my project to create controls like the ones displayed?
I can probably build this by hand, but debugging gesture recognizers and view rotation is not the most fun thing, so I'm looking for something more polished.
Thank you!
Here's a link to an open source control on cocoa controls that looks like something you could use: TDResizerView.
"TDResizerView is used to resize and rotate an imageview with single finger"
Sounds like a good place to start from, even if you need to modify it.
I've never used this particular control though, so take my word for what it's worth.
edit: Also keep in mind that on iOS, users generally expect gestures. Forcing them to use the handles instead of pinching or rotating may be bad for your user experience, depending on why you want the handles instead.
I am beginner for interactions on iphone. I have 3 buttons, one on the left, and the 2 other ones on the right. I would like to push the left button with finger and display a line real time stretching with my finger moving on screen that goes to the other button I am going to go to on the right - and then I reach the button on the right and release my finger the line stays on screen.
Where should I start in the manual to understand how to do something like this?
- please don't say page 1 ;-)
thanks for all the pointers so I can learn and write the code myself
Cheers,
geebee
Wow, uh, you're jumping right into the deep end.
First, the answer to your question is ... check out the Sample Code at developer.apple.com. By playing with those sample projects, and running them in the debugger, and reading that code, you can learn a whole lot about what you're trying to do.
Using those samples as your tutorial, refer to specific information in the reference docs also available at developer.apple.com. There are specific docs on the classes you'll be using (e.g. UIButton Class Reference), and there are high level guides that talk about different areas, like the Event Handling Guide for iOS, and Drawing and Printing Guide for iOS.
Here are some of the issues you're going to face, and some of the areas that you should read up on:
UIButtons are going to respond to your touch and won't allow any other view to receive that touch without some special handling in your code.
Check out samples that deal with UITouch events, Quartz 2D drawing, creating custom controls
Try doing this without any buttons first, that's fairly simple. Just figure out how to detect a TouchDownInside event, track the finger movement across the screen, and detect a TouchUpInside event, all in a normal UIView. (There may be a sample for this.)
I am trying to find a way to make some way for users to adjust their images for my app. I tried default "Move and Scale" but it doesn't seem to support rotation.
what I want to do is making users to move, scale, and rotate the picture to fit in the overlay/silhouette. What should I do?
Have a look at the UIGestureRecognizer class available in iOS4. This can be used to detect certain gestures like rotation, panning & pinching. Once the gesture has been detected it's up to you to add the correct transform to the picture for instance.
The gesture recognizers really are the way to go, no more touchesBegan/Ended madness. But they come at a cost, as they are iOS4 only.
Link: UIGestureRecognizer Class Reference
Refer to this code by Erica Sadun - https://github.com/erica/iphone-3.0-cookbook-/tree/master/C08-Gestures/14-Resize%20And%20Rotate/
I am trying to design another app and am struggling to think of the best way to do it. I'm after some advice please!
If you imaging a bicycle wheel in the middle of the ipad (and iPhone)... I want the user to be able to click on the tyre and spin it to the left or right. Depending on the speed of the swish will drive the speed of the wheel rotation.
It should rotate around the centre of the wheel and not move any other direction.
Do I need to use some graphics code, or simply listen for the touch, check the area they touched, then rotate the image around it's centre left or right?
Really I'm after some pointers around the methods to use - I'm not being lazy and asking for code, but if anyone knows of tutorials - that would help immensely!!
Thanks for any info.
Your best bet is to use one of the UIGestureRecognizer subclasses, probably UIPanGestureRecognizer as it includes velocity.
Apple's SimpleGestureRecognizers project will help you get started.
I need to implement 'graphing paper' in an iPhone app. The user should be presented with a grid. They user can touch individual squares to turn them on, or if they're already on, off.The user can pinch to zoom and scroll around the paper as well..
So far I'm thinking Quartz 2D + UIScrollView is the way to do this but these are both areas of iPhone development that I'm unfamiliar with. Does this seem like a reasonable strategy?
Yes, this would be the way to go. You could also create a UIView and give it a background color based off an image (+[UIColor colorWithPatternImage:]), but, myself, I'd go with option (a).