问题
I'm trying to customize the disclosure arrow appearance in my view-based NSOutlineView. I saw that it's recommended to use
- (void)outlineView:(NSOutlineView *)outlineView willDisplayOutlineCell:(id)cell forTableColumn:(NSTableColumn *)tableColumn item:(id)item
delegate method to achieve it. The problem is that this method is not called for some reason. I have 2 custom cell views - one for item and second for header item. May be this method is not called for view-based outline views? May be something became broken in Lion?
Please shed some light.
回答1:
This answer is written with OS X 10.7 in mind, for newer versions of OS X/macOS, refer to WetFish's answer
That method does not get called because it is only relevant for cell based outline views.
In a view based outline view, the disclosure triangle is a regular button in the row view of expandable rows. I don't know where it gets added, but it does, and NSView
's didAddSubview:
method handles exactly that situation of a view being added somewhere else.
Hence, subclass NSTableRowView
, and override didAddSubview:
, like this:
-(void)didAddSubview:(NSView *)subview
{
// As noted in the comments, don't forget to call super:
[super didAddSubview:subview];
if ( [subview isKindOfClass:[NSButton class]] ) {
// This is (presumably) the button holding the
// outline triangle button.
// We set our own images here.
[(NSButton *)subview setImage:[NSImage imageNamed:@"disclosure-closed"]];
[(NSButton *)subview setAlternateImage:[NSImage imageNamed:@"disclosure-open"]];
}
}
Of course, your outline view's delegate will have to implement outlineView:rowViewForItem:
to return the new row view.
Despite the name, frameOfOutlineCellAtRow:
of NSOutlineView
still gets called for view based outline views, so for the positioning of your triangle, you might want to subclass the outline view and override that method, too.
回答2:
Solution 1:
Subclass NSOutlineView and override makeViewWithIdentifier:owner:
- (id)makeViewWithIdentifier:(NSString *)identifier owner:(id)owner {
id view = [super makeViewWithIdentifier:identifier owner:owner];
if ([identifier isEqualToString:NSOutlineViewDisclosureButtonKey]) {
// Do your customization
}
return view;
}
For Source Lists use NSOutlineViewShowHideButtonKey
.
Solution 2:
Interface Builder
The button is added to the column and the identifier set to NSOutlineViewDisclosureButtonKey
.
Official documentation from NSOutlineView.h
/* The following NSOutlineView*Keys are used by the View Based NSOutlineView to create the "disclosure button" used to collapse and expand items. The NSOutlineView creates these buttons by calling [self makeViewWithIdentifier:owner:] passing in the key as the identifier and the delegate as the owner. Custom NSButtons (or subclasses thereof) can be provided for NSOutlineView to use in the following two ways:
1. makeViewWithIdentifier:owner: can be overridden, and if the identifier is (for instance) NSOutlineViewDisclosureButtonKey, a custom NSButton can be configured and returned. Be sure to set the button.identifier to be NSOutlineViewDisclosureButtonKey.
2. At design time, a button can be added to the outlineview which has this identifier, and it will be unarchived and used as needed.
When a custom button is used, it is important to properly set up the target/action to do something (probably expand or collapse the rowForView: that the sender is located in). Or, one can call super to get the default button, and copy its target/action to get the normal default behavior.
NOTE: These keys are backwards compatible to 10.7, however, the symbol is not exported prior to 10.9 and the regular string value must be used (i.e.: @"NSOutlineViewDisclosureButtonKey").
*/
APPKIT_EXTERN NSString *const NSOutlineViewDisclosureButtonKey NS_AVAILABLE_MAC(10_9); // The normal triangle disclosure button
APPKIT_EXTERN NSString *const NSOutlineViewShowHideButtonKey NS_AVAILABLE_MAC(10_9); // The show/hide button used in "Source Lists"
回答3:
Swift2 version of @Monolo's answer:
override func didAddSubview(subview: NSView) {
super.didAddSubview(subview)
if let sv = subview as? NSButton {
sv.image = NSImage(named:"icnArwRight")
sv.alternateImage = NSImage(named:"icnArwDown")
}
}
回答4:
For Swift 4.2 macOS 10.14, @WetFish's answer can be implemented as follows:
class SidebarView: NSOutlineView {
override func makeView(withIdentifier identifier: NSUserInterfaceItemIdentifier, owner: Any?) -> NSView? {
let view = super.makeView(withIdentifier: identifier, owner: owner)
if identifier == NSOutlineView.disclosureButtonIdentifier {
if let btnView = view as? NSButton {
btnView.image = NSImage(named: "RightArrow")
btnView.alternateImage = NSImage(named: "DownArrow")
// can set properties of the image like the size
btnView.image?.size = NSSize(width: 15.0, height: 15.0)
btnView.alternateImage?.size = NSSize(width: 15.0, height: 15.0)
}
}
return view
}
}
Looks quite nice!
来源:https://stackoverflow.com/questions/11127764/how-to-customize-disclosure-cell-in-view-based-nsoutlineview