如何使 UITextView 能够接收粘贴的图像

Question

我需要支持将图像粘贴到 UITextView。将图像复制到剪贴板后，“Paste”选项似乎不会弹出。当剪贴板上有文本时它会执行。

这是在自定义 UITextView 中覆盖 paste 选项的方法。但我需要有关如何获得显示开始选项的帮助...

// This gets called when user presses menu "Paste" option
- (void)paste:(id)sender{

    UIImage *image = [UIPasteboard generalPasteboard].image;

    if (image) {
        NSTextAttachment *textAttachment = [[NSTextAttachment alloc] init];
        textAttachment.image = image;
        NSAttributedString *imageString = [NSAttributedString attributedStringWithAttachment:textAttachment];
        self.attributedText = imageString;
    } else {
        // Call the normal paste action
        [super paste:sender];
    }
}

我遇到了一些相关问题，但它们对像我这样没有经验的开发人员没有帮助： How to get UIMenuController work for a custom view?,

Answer 1

我回答了我自己的问题。您所要做的就是通过覆盖此 UITextView 方法让 UITextView 说 "I can receive pasted images"：

- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
    if (action == @selector(paste:) && [UIPasteboard generalPasteboard].image)
        return YES;
    else
        return [super canPerformAction:action withSender:sender];
}

不客气。

Answer 2

谢谢@Matt，你的回答对我有帮助。只是扩展您的答案，这可能会对某些人有所帮助，

子类化 UITextview，当粘贴板中有图像时长按显示粘贴选项。

class MyTextView:UITextView {
    var onPasteImage:(()->Void)?
    override func awakeFromNib() {
        super.awakeFromNib()
    }
    override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
        if action == #selector(paste(_:)) && UIPasteboard.general.image != nil {
            return true
        }else{
            return super.canPerformAction(action, withSender: sender)
        }
    }
    
    override func paste(_ sender: Any?) {
        super.paste(sender)
        if UIPasteboard.general.image != nil {
            onPasteImage?()
        }
    }
}

并等待 onPasteImage 在文本视图中点击粘贴时调用闭包，

inputFieldForReply.textView.onPasteImage = { [weak self] in
    if let image = UIPasteboard.general.image {
        // Process pasted image
    }
}

如何使 UITextView 能够接收粘贴的图像

How to enable UITextView to receive pasted images

ios

objective-c

cocoa-touch

uitextview

uimenucontroller