How to resize NSTextView according to its content?

问题

I am trying to set an attributed string within NSTextView. I want to increase its height based on its content, initially it is set to some default value.

So I tried this method:

I set content in NSTextView. When we set some content in NSTextView its size automatically increases. So I increased height of its super view that is NSScrollView to its height, but NSScrollView is not getting completely resized, it is showing scroller on right.

float xCoordinate = 15.0;

[xContentViewScroller setFrame:NSMakeRect(xCoordinate, 0.0, 560.0, 10.0)];

[[xContentView textStorage] setAttributedString:xContents];

float xContentViewScrollerHeight = [xfContentView frame].size.height + 2;

[xContentViewScroller setFrame:NSMakeRect(xCoordinate, 0.0, 560.0, xContentViewScrollerHeight)];

Can anyone suggest me some way or method to resolve this issue. By doing google search I found that in UITextView there is contentSize method which can get size of its content, I tried to find similar method in NSTextView but could not get any success :(

回答1:

Ask the text view for its layout manager and its text container. Then, force the layout manager to perform layout, and then ask the layout manager for the used rectangle for the text container.

回答2:

NSTextView *textView = [[NSTextView alloc] init];
textView.font = [NSFont systemFontOfSize:[NSFont systemFontSize]];
textView.string = @"Lorem ipsum";

[textView.layoutManager ensureLayoutForTextContainer:textView.textContainer];

textView.frame = [textView.layoutManager usedRectForTextContainer:textView.textContainer];

回答3:

Based on @Peter Hosey's answer, here is an extension to NSTextView in Swift 4.2:

extension NSTextView {

    var contentSize: CGSize {
        get {
            guard let layoutManager = layoutManager, let textContainer = textContainer else {
                print("textView no layoutManager or textContainer")
                return .zero
            }

            layoutManager.ensureLayout(for: textContainer)
            return layoutManager.usedRect(for: textContainer).size
        }
    }
}

回答4:

+ (float)heightForString:(NSString *)myString font:(NSFont *)myFont andWidth:(float)myWidth andPadding:(float)padding {
     NSTextStorage *textStorage = [[NSTextStorage alloc] initWithString:myString];
     NSTextContainer *textContainer = [[NSTextContainer alloc] initWithContainerSize:NSMakeSize(myWidth, FLT_MAX)];
     NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];
     [layoutManager addTextContainer:textContainer];
     [textStorage addLayoutManager:layoutManager];
     [textStorage addAttribute:NSFontAttributeName value:myFont
                    range:NSMakeRange(0, textStorage.length)];
     textContainer.lineFragmentPadding = padding;

     (void) [layoutManager glyphRangeForTextContainer:textContainer];
     return [layoutManager usedRectForTextContainer:textContainer].size.height;
}

I did the function using this reference: Documentation

Example:

float width = textView.frame.size.width - 2 * textView.textContainerInset.width;
float proposedHeight = [Utils heightForString:textView.string font:textView.font andWidth:width
                                   andPadding:textView.textContainer.lineFragmentPadding];

来源：https://stackoverflow.com/questions/2654580/how-to-resize-nstextview-according-to-its-content

标签

cocoa

nstextview