macOS Rich Text Editor

The macOS Rich Text Editor library allows for rich text editing via a native NSTextView. You will need to implement much of the UI yourself (buttons, handling selection changes via the delegate protocol, etc.). The RTE just handles the bold/italic/bulleted lists/etc. formatting for you. The sample should give you some guidance on how this could be accomplished.

To use this library, you only need eight files:

- RichTextEditor.h/m
- NSFont+RichTextEditor.h/m
- NSAttributedString+RichTextEditor.h/m
- WZProtocolInterceptor.h/m

You can copy these files directly into your project, or you can choose to build and use the .framework output. Remember to open the .xcworkspace file when exploring this project.

This library is based upon Deadpikle's iOS Rich Text Editor, which was edited from the original iOS rich text editor by aryaxt.

Features:

• Bold
• Italic
• Underline
• Font
• Font size
• Text background color
• Text foreground color
• Text alignment
• Paragraph indent/outdent
• Bulleted lists

Compatibility

The rich text editor is compatible with macOS 10.10+. It might work on older versions, but this has not been tested.

Keyboard Shortcuts

Shortcut	Action
⌘ + B	Toggle bold
⌘ + I	Toggle italic
⌘ + U	Toggle underline
⌘ + ⇧ + >	Increase font size
⌘ + ⇧ + <	Decrease font size
⌘ + ⇧ + L	Toggle bulleted list
⌘ + ⇧ + N	If in bulleted list, leave bulleted list
⌘ + ⇧ + T	Decrease indent
⌘ + T	Increase indent

By default, all keyboard shortcuts are enabled. If you want to selectively enable some keyboard shortcuts, implement the RichTextEditorDataSource method - (RichTextEditorShortcut)enabledKeyboardShortcuts. If you want to do this, don't forget to set the rteDataSource!

Scaling Text [TODO: move to Wiki]

If you want to scale text, you can use code similar to the following (based on http://stackoverflow.com/a/14113905/3938401):

// http://stackoverflow.com/a/14113905/3938401
@interface ...
@property CGFloat scaleFactor;
@end

@implementation ...

-(void)viewDidLoad {
    self.scaleFactor = 1.0f;
    ...
}

- (void)setScaleFactor:(CGFloat)newScaleFactor adjustPopup:(BOOL)flag {
    CGFloat oldScaleFactor = self.scaleFactor;
    if (self.scaleFactor != newScaleFactor) {
        NSSize curDocFrameSize, newDocBoundsSize;
        NSView *clipView = [self.notesTextView superview];
        self.scaleFactor = newScaleFactor;
        // Get the frame. The frame must stay the same.
        curDocFrameSize = [clipView frame].size;
        // The new bounds will be frame divided by scale factor
        newDocBoundsSize.width = curDocFrameSize.width / self.scaleFactor;
        newDocBoundsSize.height = curDocFrameSize.height / self.scaleFactor;
    }
    self.scaleFactor = newScaleFactor;
    [self scaleChanged:oldScaleFactor newScale:newScaleFactor];
}

- (void)scaleChanged:(CGFloat)oldScale newScale:(CGFloat)newScale {
    CGFloat scaler = newScale / oldScale;
    [self.notesTextView scaleUnitSquareToSize:NSMakeSize(scaler, scaler)];
    // For some reason, even after ensuring the layout and displaying, the wrapping doesn't update until text is messed
    // with. This workaround "fixes" that. Since we need it anyway, I removed the ensureLayoutForTextContainer:
    // (from the SO post) and the documentation-implied [self.notesTextView display] calls.
    [[self.notesTextView textStorage] appendAttributedString:[[NSAttributedString alloc] initWithString:@""]];
}

@end

Credits

Original Rich Text Editor code by aryaxt at the iOS Rich Text Editor repo. WZProtocolInterceptor is from this SO post.