xcode Swift：如何更改 NSImage 图像源？
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Swift: How to change NSImage image source?
提问by udondan
I'm a newbee with XCode and Swift. Trying to simply set an image in my view in an OS X application. The image should be loaded from the web, but I think that doesn't matter.
我是 XCode 和 Swift 的新手。试图在 OS X 应用程序中简单地在我的视图中设置图像。图像应该从网络加载，但我认为这无关紧要。
I created a new Cocoa App, have a list view which works. In the XIB for the list row I have placed an "Image View" element and with this I can display a static image in each row.
我创建了一个新的 Cocoa App，有一个有效的列表视图。在列表行的 XIB 中，我放置了一个“图像视图”元素，这样我就可以在每一行中显示一个静态图像。
Now I want to change the image URL when the row loads. I dragged the line from the image to my controller class, which added the @IBOutletto the code.
现在我想在行加载时更改图像 URL。我将图像中的线条拖到我的控制器类中，该类将 加到@IBOutlet代码中。
This is my code of the controller class:
这是我的控制器类代码：
import Cocoa
class ListRowViewController: NSViewController {
@IBOutlet weak var rowImage: NSImageView!
override var nibName: String? {
return "ListRowViewController"
}
override func loadView() {
super.loadView()
var url = NSURL(fileURLWithPath: "http://example.com/some-image.png")
var image = NSImage(byReferencingURL: url!)
self.rowImage.image(image)
}
}
Now the very funnyfrustrating error message from the last statement (self.rowImage.image(image)) is
现在来自最后一条语句 ( )的非常有趣的令人沮丧的错误消息self.rowImage.image(image)是
Cannot convert the expression's type 'NSImage' to type 'NSImage?'.
无法将表达式的类型“NSImage”转换为“NSImage?”类型。
OK. What does that mean and how do I fix it? Is that somehow related to optionals? I experimented with ?'s and !'s but just can't figure out what XCode expects from me.
好的。这是什么意思，我该如何解决？这在某种程度上与选项有关吗？我尝试了?'s 和!'s 但就是无法弄清楚 XCode 对我的期望。
采纳答案by rintaro
imageof NSImageViewis a property, you can just assign to it.
imageofNSImageView是一个属性，你可以分配给它。
self.rowImage.image = image
And, your URL is wrong NSURL(fileURLWithPath:)is for local files. Use NSURL(string:)instead.
而且，您的 URL 是错误的NSURL(fileURLWithPath:)，用于本地文件。使用NSURL(string:)来代替。
var url = NSURL(string: "http://example.com/some-image.png")
