我对NSTextView子类有问题。我的视图包含带有自定义属性的属性字符串,因此我必须实现以下粘贴板方法,以确保将自定义属性复制到粘贴板上。
writeSelection(to:type:)
readSelection(from:type:)
override func readSelection(from pboard: NSPasteboard, type: String) -> Bool {
// Manually reads the text on the pasteboard, and write it to textStorage
if type == astroBoardAttributedString {
if let string = pboard.string(forType: astroBoardAttributedString) {
let attrString = NSAttributedString(string: string)
self.textStorage?.replaceCharacters(in: self.rangeForUserTextChange, with: attrString)
return true
}
}
return super.readSelection(from: pboard, type: type)
}
现在的问题是,当我选择文本并将其向上拖动(例如从第5行拖动到第1行下)时,文本会正确插入第1行下,但是系统会尝试从第5行原来的位置删除文本,因为第1行下添加了一行,所以现在包含第4行。
/*
line 1 <-- Drop after this line
line 2
line 3
line 4
line 5 <-- Drag from this line
The expected outcome is
line 1
line 5
line 2
line 3
line 4
The actual resulting outcome is
line 1
line 5
line 2
line 3
line 5
What happens is
line 1
line 5 <-- Line inserted here (correct)
line 2
line 3
line 4 <-- This line is removed instead :(
line 5 <-- This is the line that should be removed.
*/
