I try to do customized tableviewCell with imageView in my chat app.
And I need to do 3x3 grid images in each cell.
I face a problem that the imageView memory problem.
How to solve the cell contain 9 imageviews in each cell to prevent memory increase.
Or any good idea to solve it.
I need to decrease memory.
Thanks.
This is my code:
case .group:
var drawSequence:[Int] = [Int]()
var drawIcons:[String] = [String]()
let string:String = chatroom.users
let tempArr = string.components(separatedBy: ",")
var stringArr = Array<String>()
for a in tempArr {
var b = a.replacingOccurrences(of: "\"", with: "")
b = b.replacingOccurrences(of: "[", with: "")
b = b.replacingOccurrences(of: "]", with: "")
stringArr.append(b)
}
stringArr.forEach({ (id) in
drawIcons.append(id)
})
let g:CGFloat = 1
var x:CGFloat = g
var y:CGFloat = g
var w:CGFloat = (defaultBigIconWidth - g)/3 - g
switch drawIcons.count {
case let count where count >= 9:
drawSequence = [3,3,3]
break
case 8:
drawSequence = [2,3,3]
break
case 7:
drawSequence = [1,3,3]
break
case 6:
drawSequence = [3,3]
y = defaultBigIconWidth/2-w
break
case 5:
drawSequence = [2,3]
y = defaultBigIconWidth/2-w
break
case 4:
w = (defaultBigIconWidth - g)/2 - g
drawSequence = [2,2]
y = defaultBigIconWidth/2-w
break
case 3:
w = (defaultBigIconWidth - g)/2 - g
drawSequence = [1,2]
y = defaultBigIconWidth/2-w
break
case 2:
w = (defaultBigIconWidth - g)/2 - g
drawSequence = [2]
y = (defaultBigIconWidth-w)/2
break
default:
break
}
for row in drawSequence {
switch row {
case 1:
x = (defaultBigIconWidth-w)/2
break
case 2:
x = defaultBigIconWidth/2-w
break
default:
x = g
break
}
for _ in 0..<row {
let id = drawIcons.removeFirst()
let ui:UIImageView = GeneratorAvatarImageView()
ui.frame = CGRect(x: x, y: y, width: w, height: w)
icon.addSubview(ui)
if id == currentUser.id {
user = contacts[currentUser.id]
ImageFromUrl(imageView: ui, url: (user?.avatar)!, type: "user")
}else{
user = contacts[id]
ImageFromUrl(imageView: ui, url: (user?.avatar)!, type: "user")
}
x += w+g
}
y += w+g
}
break
func ImageFromUrl(imageView:UIImageView,url:String,type:String) {
if url.isEmpty {
imageView.image = #imageLiteral(resourceName: "defaultIcon")
print("Url is empty.")
return
}
var documentsDirectoryURL:URL
if type == "user" {
documentsDirectoryURL = try! FileManager().url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true).appendingPathComponent("Image/User/")
let exist = FileManager.default.fileExists(atPath: documentsDirectoryURL.path)
if !exist {
do {
try FileManager.default.createDirectory(atPath: documentsDirectoryURL.path, withIntermediateDirectories: true, attributes: nil)
} catch let error as NSError {
debug(object: error)
}
}
}
// create a name for your image
let fileName = url.md5()
let fileURL = documentsDirectoryURL.appendingPathComponent(fileName)
let urlString = URL(string: url)
if let image = UIImage(contentsOfFile: fileURL.path) {
imageView.image = image
return
}
DispatchQueue.global().async {
let data = try? Data(contentsOf: urlString!) //make sure your image in this url does exist, otherwise unwrap in a if let check / try-catch
if data != nil
{
if let image = UIImage(data: data!)
{
if !FileManager.default.fileExists(atPath: fileURL.path) {
var c = [UInt32](repeating: 0, count: 1)
(data! as NSData).getBytes(&c, length: 1)
switch (c[0]) {
case 0xFF:
print("Download jpg: \(url)")
if let jpegData = UIImageJPEGRepresentation(image, 0.5) {
do {
try jpegData.write(to: fileURL, options: .atomic)
} catch {
debug(object: error)
}
}
case 0x89:
print("Download png: \(url)")
if let pngData = UIImagePNGRepresentation(image) {
do {
try pngData.write(to: fileURL, options: .atomic)
} catch {
debug(object: error)
}
}
case 0x47:
print("Download gif: \(url)")
default:
print("Download unknown: \(c[0])\(url)")
}
} else {
// debug(object:"file already exists")
}
DispatchQueue.main.async {
imageView.image = image
}
}
}
}
}
func GeneratorAvatarImageView() -> UIImageView {
let imageview = UIImageView()
imageview.layer.masksToBounds = true
imageview.layer.cornerRadius = 2
imageview.backgroundColor = UIColor.clear
imageview.contentMode = UIViewContentMode.scaleAspectFill
return imageview
}
