Drag multiple images separately in swift-CodePudding

I have just started coding and this is my first project, and I want to drag couple images set on the screen separately and leave them where they are dragged. However currently I could manage dragging images separately but comes back in their original position... what should I change if I want to leave each images where they are dragged.

HStack {
    ForEach(stickers) { sticker in
        Image(sticker.name)
            .resizable()
            .frame(width: self.screenWidth*0.2, height: self.screenWidth*0.2)
            .offset(x: self.selectedSticker == sticker ? self.dragOffset.width : 0,
                    y: self.selectedSticker == sticker ? self.dragOffset.height : 0)
            .gesture(
                DragGesture()
                    .updating(self.$dragOffset, body: { (value, state, transaction) in
                        if nil == self.selectedSticker {
                            self.selectedSticker = sticker
                        }
                        state = value.translation
                        
                    }).onEnded { _ in self.selectedSticker = nil }
            )
    }
}

CodePudding user response：

It seems that once the sticker is no longer the selected.sticker, its offset returns to zero. You'd need to set a variable that saves the images' locations after they are updated.

You could perhaps add another variable, offset, to Sticker:

struct Sticker: ... {
    var offset = CGSize.zero
    ...
}

And then store the offset value for each sticker in sticker.offset in .onEnded:

HStack {
    ForEach(stickers) { sticker in
        Image(sticker.name)
            .resizable()
            .frame(width: self.screenWidth*0.2, height: self.screenWidth*0.2)
            .offset(x: self.selectedSticker == sticker ? self.dragOffset.width : sticker.offset.width,
                    y: self.selectedSticker == sticker ? self.dragOffset.height : sticker.offset.height)
            .gesture(
                DragGesture()
                    .updating(self.$dragOffset, body: { (value, state, transaction) in
                        if nil == self.selectedSticker {
                            self.selectedSticker = sticker
                        }
                        state = value.translation
                    })
                    .onEnded { _ in
                        sticker.offset = dragOffset
                        self.selectedSticker = nil
                    }
            )
    }
}