我正在开发OS X应用程序,我似乎无法让拖放工作。我用Google搜索了很多,但是关于这个主题的大多数帖子都至少有几年的历史,而且没有一个帖子告诉我在思想中缺少的链接。
无论如何,这是我正在努力做的事情。我的桌面上有一个图像,我希望能够将其拖放到我的自定义NSView中。自定义视图是名为CircularImageView的自定义NSView的子对象,并且是图层备份的,并且仅在屏幕上显示圆形图像。
以下是代码:
import Cocoa
import MCTools
@objc public protocol DragAndDropCircularImageViewDelegate {
func imageDumped(sender: AnyObject!)
}
@IBDesignable @objc public class DragAndDropCircularImageView: CircularImageView {
// This class provides the Drag And Drop Feature to the CircularImageView Class.
// MARK: New in this class
var highlight: Bool = false
public var delegate: DragAndDropCircularImageViewDelegate?
private func registerForDraggedImages() {
self.registerForDraggedTypes(NSImage.imageTypes())
}
// MARK: CircularImageView Stuff
public override var image: NSImage? {
didSet {
if let newImage = image {
delegate?.imageDumped(self)
}
}
}
public required init?(coder: NSCoder) {
super.init(coder: coder)
self.registerForDraggedImages()
}
public override init(frame frameRect: NSRect) {
super.init(frame: frameRect)
self.registerForDraggedImages()
}
public override func updateLayer() {
super.updateLayer()
if highlight == true {
}
}
// MARK: NS Dragging Destination Protocol
public override func draggingEntered(sender: NSDraggingInfo) -> NSDragOperation {
// When a drag enters our drop zone.
if NSImage.canInitWithPasteboard(sender.draggingPasteboard()) {
if ((sender.draggingSourceOperationMask().rawValue & NSDragOperation.Copy.rawValue) > 0) {
highlight = true
self.needsLayout = true
sender.enumerateDraggingItemsWithOptions(.Concurrent, forView: self, classes: [NSPasteboardItem.self], searchOptions: [NSPasteboardURLReadingContentsConformToTypesKey: self], usingBlock: { (draggingItem, idx, stop) -> Void in
return
})
}
return NSDragOperation.Copy
}
return NSDragOperation.None
}
public override func draggingExited(sender: NSDraggingInfo?) {
// When drag exits our drop zone remove highlight of the drop zone.
println("\(self)draggingExited")
highlight = false
self.needsLayout = true
}
public override func prepareForDragOperation(sender: NSDraggingInfo) -> Bool {
// Update view for hovering drop.
println("\(self)prepareForDragOperation")
highlight = false
self.needsLayout = true
// Can we accept the drop?
return NSImage.canInitWithPasteboard(sender.draggingPasteboard())
}
public override func performDragOperation(sender: NSDraggingInfo) -> Bool {
// Handle the drop data.
println("\(self)performDragOperation \(sender)")
if NSImage.canInitWithPasteboard(sender.draggingPasteboard()) {
self.image = NSImage(pasteboard: sender.draggingPasteboard())
}
return true
}
// MARK: Interface Builder Stuff
}
我看过一些我应该使用的帖子:
self.registerForDraggedTypes([NSFilenamesPboardType])
而不是:
self.registerForDraggedTypes(NSImage.imageTypes())
但是这似乎不适用于我的情况,当我使用NSFileNamesPboardType时,即使在调用任何NSDraggingDestination协议消息之前,我也会收到以下调试消息:
2015-05-07 11:07:19.583 CircularImageViewTest[44809:14389647] -[CircularView.DragAndDropCircularImageView copyWithZone:]: unrecognized selector sent to instance 0x608000166d80
(lldb) p 0x608000166d80
(Int) $R0 = 106102873550208
我不明白这是如何运作的。在某个地方框架尝试copyWithZone一个整数?任何人都可以向我解释这个吗?
任何帮助将不胜感激。提前谢谢。
答案 0 :(得分:0)
好的,下面的代码可行。这一切都是由draggingEntered中的sender.enumerateDraggingItemsWithOptions引起的。 Apple框架调用时出现问题。
import Cocoa
import MCTools
@objc public protocol DragAndDropCircularImageViewDelegate {
func imageDumped(sender: AnyObject!)
}
@IBDesignable @objc public class DragAndDropCircularImageView: CircularImageView {
// This class provides the Drag And Drop Feature to the CircularImageView Class.
// MARK: New in this class
var highlight: Bool = false
public weak var delegate: DragAndDropCircularImageViewDelegate?
private func registerForDraggedImages() {
// self.registerForDraggedTypes(NSImage.imageTypes())
self.registerForDraggedTypes([NSFilenamesPboardType])
}
// MARK: CircularImageView Stuff
public override var image: NSImage? {
didSet {
if let newImage = image {
delegate?.imageDumped(self)
}
}
}
public required init?(coder: NSCoder) {
super.init(coder: coder)
self.registerForDraggedImages()
}
public override init(frame frameRect: NSRect) {
super.init(frame: frameRect)
self.registerForDraggedImages()
}
public override func updateLayer() {
super.updateLayer()
if highlight == true {
}
}
// MARK: NS Dragging Destination Protocol
public override func draggingEntered(sender: NSDraggingInfo) -> NSDragOperation {
// When a drag enters our drop zone.
if NSImage.canInitWithPasteboard(sender.draggingPasteboard()) {
if ((sender.draggingSourceOperationMask().rawValue & NSDragOperation.Copy.rawValue) > 0) {
highlight = true
self.needsLayout = true
}
return NSDragOperation.Copy
}
return NSDragOperation.None
}
public override func draggingExited(sender: NSDraggingInfo?) {
// When drag exits our drop zone remove highlight of the drop zone.
println("\(self)draggingExited")
highlight = false
self.needsLayout = true
}
public override func prepareForDragOperation(sender: NSDraggingInfo) -> Bool {
// Update view for hovering drop.
println("\(self)prepareForDragOperation")
highlight = false
self.needsLayout = true
// Can we accept the drop?
return NSImage.canInitWithPasteboard(sender.draggingPasteboard())
}
public override func performDragOperation(sender: NSDraggingInfo) -> Bool {
// Handle the drop data.
println("\(self)performDragOperation \(sender)")
if NSImage.canInitWithPasteboard(sender.draggingPasteboard()) {
self.image = NSImage(pasteboard: sender.draggingPasteboard())
self.delegate!.imageDumped(self)
}
return true
}
// MARK: Interface Builder Stuff
}