如何使用Swift正確地在照片上放置圖像視圖

Question

目前，我可以在頂部保存帶有圖像的照片，但是頂部圖像不在預覽屏幕上顯示的座標上視圖。

fileprivate func mergeUIViews() -> UIImage? 
{ 
    let bottomImage = photo 
    let topImage = uiViewInstance.image 

    let bottomImageHeight = bottomImage.size.height 
    let bottomImageWidth = bottomImage.size.width 

    let topImageHeight = uiViewInstance.frame.height 
    let topImageWidth = uiViewInstance.frame.width 
    let topImageOrigin = uiViewInstance.frame.origin 

    let bottomImageSize = CGSize(width: bottomImageWidth, height: bottomImageHeight) 
    let topImageSize = CGSize(width: topImageWidth, height: topImageHeight) 

    // Merge images 

    UIGraphicsBeginImageContextWithOptions(bottomImageSize, false, 0.0) 

    bottomImage.draw(in: CGRect(origin: CGPoint.zero, size: bottomImageSize)) 
    topImage .draw(in: CGRect(origin: topImageOrigin, size: topImageSize)) // Where I believe the problem exists 
    let newImage = UIGraphicsGetImageFromCurrentImageContext() 

    UIGraphicsEndImageContext() 

    return newImage 
} 

Answer 1

什麼工作，而不是使用實際拍攝照片的大小，則照片尺寸設置爲視圖控制器尺寸的視圖。這導致整個屏幕的期望輸出顯示合併的照片和重疊圖像的原點的適當點。

fileprivate func mergeUIViews() -> UIImage? 
{ 
    let bottomImage = photo 
    let topImage = uiViewInstance.image 

    let bottomImageSize = self.view.frame.size 

    let topImageHeight = uiViewInstance.frame.height 
    let topImageWidth = uiViewInstance.frame.width 
    let topImageOrigin = uiViewInstance.frame.origin 
    let topImageSize = uiViewInstance.frame.size 

    // Merge images 

    UIGraphicsBeginImageContextWithOptions(bottomImageSize, false, 0.0) 

    bottomImage.draw(in: CGRect(origin: CGPoint.zero, size: bottomImageSize)) 
    topImage .draw(in: CGRect(origin: topImageOrigin, size: topImageSize)) // Where I believe the problem exists 
    let newImage = UIGraphicsGetImageFromCurrentImageContext() 

    UIGraphicsEndImageContext() 

    return newImage 
}