In my App I have a full-screen UIScrollView where the content is a UIImageView containing a map image which is about 2000px square (i.e. larger than the UIScrollView).
Currently, I plot a path across the map and animate a "beacon" image along it using a CAKeyFrameAnimation, which works great.
What I would like to be able to do is to make the UIScrollView content move with the animation in such a way as to keep the beacon image in the centre of the screen (giving the user the impression of tracking along the path).
Any suggestions on how I might achieve this?
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In ViewController I have a big ImageView whose image is captured with a ImagePicker. I want the user to be allowed to zoom in/out the image and then pan it but always inside the ImageView dimensions which must not enlarge, move or dwindle. I have seen I could add a ScrollView to ImageView but I can't figure out how to do that.
Moreover: is it possible to zoom in/out more than one ImageView at a time? I mean I have some smaller imageViews floating upon a bigger imageView. Is it possible to zoom everything all together?
There are plenty of excellent scrollview demo's around.
These will show you where and how to add override functions to implement what you need...
If you have different UIImage Views you can set the zoom programmatically to match the image being "zoomed" ... try experimenting with [UIImage].zoomScale. and the image offset. Its going to get complicated if they are different sizes as you will have to take account of scale when mirroring offset and zoom changes.
I have to show in zoom of a selected area of image continuously. Means if you are changing position simultaneously zoom also to be change. I don't know how to implement this.
UIScrollView has a great method - zoomToRect:animated: - that allows you to zoom on a specific rect. If you have a UIImageView sitting on a UIScrollView then you can zoom around the image view using this one simple method.
I have a UIViewController that implements a UIScrollView with the UIScrollViewDelegate. Attached to it is an UIImageView for which the user must crop the photo via zooming it and panning to fill the entire length of the screen. After the user has finished cropping and they hit done, the original UIImage gets sent to the next UIViewController.
I'm wondering, is there anyway, using the original image, to display it in a UIScrollView and allow the user to zoom and pan it so ONLY the cropped area gets shown? IE none of the image that was outside of the cropped area gets shown in zooming and panning? Is there a way to do this without explicitly cropping the image?
This might head you in the right direction: Displaying part of an image
Not to sure if this will work with the way you are displaying it. But if it does it could be a simple solution. You can also read through UIScrollviews and maybe use panGestureRecognizer and pinchGestureRecognizer to limit the area they can zoom and pan.
Set the content size of the UIScrollView to the rect of the cropped area.
I want to change my view size using user touch input.
What I know and will be trying is using TouchesMoved method and then finding the nearest vertex of the view to the touch, make the view increase in that direction using animation.
But there are few problems I have before I start.
1) The camera app has same functionality in cropping photo. There is a grid displaying actual crop area. I don't know how to display that grid. I don't have any knowledge of opengl. I would like to have that as a indication of user is in edit mode?
2) The camera app crop functionality is also of changing the size using user touch input but it only changes view size, if the touch is near the four vertices of the view. From what I know there is a method to check if the touch is in a specific rect CGRectContainsPoint but how do I filter it to bounds of the view?
Edit
I tried yinkou answer, downloaded from Git.
Now the real question is in the git Xcode project. There is a view which has image as a contentView and if user drag that view, the image also changes shape based on view resizing.
I am doing this in a camera app. I attached AVCaptureVideoPreviewLayer as a contentView. Now my view is resizing but the AVCaptureVideoPreviewLayer stays the same size. Am I doing something wrong or is it that AVCaptureVideoPreviewLayer won't increase?
And happily, there's a control out there:
https://github.com/spoletto/SPUserResizableView
In one of my apps I am trying to combine two UIImageViews into a single UIImage. Bottom one is from the camera and the top one is something like a badge. The user can drag, rotate and scale the one at the top.
My question is, how can i save these two UIImageViews into a single UIImage at the end of all drag, rotate and scale operations?
Edit: I want to keep the original size of the bottom image.
This post : Saving UIView contents in iOS 4 with real size of the images inside (i.e. scale contentes up for save) shows how you can get a UIImage from any UIView.
Basically, you can adapt its solution, using a UIView container for your 2 UIImageViews.