iphone - how to overlap image on another images while dragging it in iOS? -

I have created a Jigasav game. In it, I split the image into 3x3 matrix and displayed on screen (ie [Self.view addSubView: imageview] like I've added all 9 image tiles). Now when I pull an image tile in another image tile, it sometimes goes down on the image or sometimes below the image to solve the image (like the first image to look like the default behavior of iOS Is displayed below all the images and the last uploaded image appears at the top, drag the user into the image attached images) Now I feel that when I drag any image tile, it is the top of the remaining images And should be visible. Appears on top of the previous image similar to the previous image.

< Whenever an image is touched to drag it, you can call it bringSubviewToFront

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