NSBrowser bindings changes and general binding improvements

ChangeLog

@@ -1,3 +1,11 @@
+2024-11-08 Gregory John Casamento <[email protected]>
+
+	* Headers/AppKit/NSBrowser.h: Add dictionary to hold relationships.
+	* Source/NSBrowser.m: Add logic in methods to support binfings,
+	expose bindings in +initialize.
+	* Source/NSTextFieldCell.m: Minor fix to NSTextField for displaying
+	binding values.
+
 2024-10-31 Richard Frith-Macdonald <[email protected]>
 
 	* Source/GSServicesManager.m: fix -laterDate: conditionals to be true

Headers/AppKit/NSBrowser.h

@@ -37,6 +37,7 @@
 @class NSArray;
 @class NSIndexPath;
 @class NSIndexSet;
+@class NSMutableDictionary;
 
 @class NSCell;
 @class NSEvent;
@@ -100,6 +101,7 @@ APPKIT_EXPORT_CLASS
   NSBrowserColumnResizingType _columnResizing;
 
   BOOL _itemBasedDelegate;
+  NSMutableDictionary *_columnDictionary;
 }
 
 //

Source/NSBrowser.m

@@ -16,7 +16,7 @@
    Date: September 2002
    Author:  Gregory Casamento <[email protected]>
    Date: July 2024
-   Note: Added support for 10.6+ delegate methods.
+   Note: Added support for 10.6+ delegate methods. Added bindings support
 
    This file is part of the GNUstep GUI Library.
 
@@ -56,10 +56,13 @@
 #import "AppKit/NSColor.h"
 #import "AppKit/NSFont.h"
 #import "AppKit/NSGraphics.h"
+#import "AppKit/NSKeyValueBinding.h"
 #import "AppKit/NSMatrix.h"
 #import "AppKit/NSScroller.h"
 #import "AppKit/NSScrollView.h"
 #import "AppKit/NSTableHeaderCell.h"
+#import "AppKit/NSTreeController.h"
+#import "AppKit/NSTreeNode.h"
 #import "AppKit/NSEvent.h"
 #import "AppKit/NSViewController.h"
 #import "AppKit/NSWindow.h"
@@ -260,6 +263,10 @@ - (NSBorderType) _resolvedBorderType;
 - (void) _themeDidActivate: (NSNotification*)notification;
 @end
 
+// Category to handle bindings
+@interface NSBrowser (GSBindingsPrivate)
+@end
+
 //
 // NSBrowser implementation
 //
@@ -2268,7 +2275,7 @@ - (void) setDelegate: (id)anObject
   _itemBasedDelegate = NO;
 
   if ([anObject respondsToSelector:
-		  @selector(browser:numberOfChildrenOfItem:)]
+		 @selector(browser:numberOfChildrenOfItem:)]
       && [anObject respondsToSelector:
 		    @selector(browser:child:ofItem:)]
       && [anObject respondsToSelector:
@@ -2486,6 +2493,10 @@ + (void) initialize
 	}
 
       [self _themeDidActivate: nil];
+
+      // Bindings...
+      [self exposeBinding: NSContentBinding];
+      [self exposeBinding: NSContentValuesBinding];
     }
 }
 
@@ -2558,6 +2569,7 @@ - (id) initWithFrame: (NSRect)rect
 
   // Item based delegate, 10.6+
   _itemBasedDelegate = NO;
+  _columnDictionary = [[NSMutableDictionary alloc] init];
 
   [[NSNotificationCenter defaultCenter]
     addObserver: self
@@ -2583,6 +2595,7 @@ - (void) dealloc
   RELEASE(_pathSeparator);
   RELEASE(_horizontalScroller);
   RELEASE(_browserColumns);
+  RELEASE(_columnDictionary);
   TEST_RELEASE(_charBuffer);
 
   [super dealloc];
@@ -3009,6 +3022,7 @@ - (id) initWithCoder: (NSCoder*)aDecoder
 
       // Item based delegate, 10.6+
       _itemBasedDelegate = NO;
+      _columnDictionary = [[NSMutableDictionary alloc] init];
 
       // Horizontal scroller
       _scrollerRect.origin.x = bs.width;
@@ -3296,10 +3310,19 @@ - (void) _remapColumnSubviews: (BOOL)fromFirst
 - (id) _itemForColumn: (NSInteger)column
 {
   id item = nil;
-
+  GSKeyValueBinding *theBinding;
+  theBinding = [GSKeyValueBinding getBinding: NSContentBinding
+				   forObject: self];
   if (column == 0)
     {
-      item = [_browserDelegate rootItemForBrowser: self];
+      if (theBinding == nil)
+	{
+	  item = [_browserDelegate rootItemForBrowser: self];
+	}
+      else
+	{
+	  item = nil; // [NSNull null];
+	}
     }
   else
     {
@@ -3319,7 +3342,20 @@ - (id) _itemForColumn: (NSInteger)column
 		{
 		  id cell = [selectedCells objectAtIndex: 0];
 
-		  item = [cell objectValue];
+		  if (theBinding != nil)
+		    {
+		      NSNumber *colNum = [NSNumber numberWithInteger: col];
+		      NSArray *array = [_columnDictionary objectForKey: colNum];
+		      if ([array count] > 0)
+			{
+			  NSInteger row = [self selectedRowInColumn: col];
+			  item = [array objectAtIndex: row];
+			}
+		    }
+		  else
+		    {
+		      item = [cell objectValue];
+		    }
 		}
 	    }
 	}
@@ -3328,22 +3364,104 @@ - (id) _itemForColumn: (NSInteger)column
   return item;
 }
 
+- (NSString *) _keyPathForValueBinding
+{
+  NSString *keyPath = nil;
+  NSDictionary *info = [GSKeyValueBinding infoForBinding: NSContentValuesBinding
+					       forObject: self];
+  if (info != nil)
+    {
+      NSString *ikp = [info objectForKey: NSObservedKeyPathKey];
+      NSUInteger location = [ikp rangeOfString: @"."].location;
+
+      keyPath = (location == NSNotFound ? ikp : [ikp substringFromIndex: location + 1]);
+    }
+
+  return keyPath;
+}
+
 /* Loads column 'column' (asking the delegate). */
 - (void) _performLoadOfColumn: (NSInteger)column
 {
-  NSBrowserColumn *bc;
-  NSScrollView *sc;
-  NSMatrix *matrix;
-  NSInteger i, rows, cols;
+  NSBrowserColumn *bc = nil;
+  NSScrollView *sc = nil;
+  NSMatrix *matrix = nil;
+  NSInteger i = 0, rows = 0, cols = 0;
   id child = nil;
   id item = nil;
+  NSNumber *colNum = nil;
+  NSTreeController *tc = nil;
+  NSArray *children = nil;
 
   if (_itemBasedDelegate)
     {
+      GSKeyValueBinding *theBinding;
+
+      theBinding = [GSKeyValueBinding getBinding: NSContentBinding
+				       forObject: self];
+
       item = [self _itemForColumn: column];
+      if (theBinding != nil)
+	{
+	  id observedObject = [theBinding observedObject];
+
+	  rows = 0;
+	  colNum = [NSNumber numberWithInteger: column];
+	  if ([observedObject isKindOfClass: [NSTreeController class]])
+	    {
+	      tc = (NSTreeController *)observedObject;
+
+	      if (item == nil)
+		{
+		  NSTreeNode *node = (NSTreeNode *)[theBinding destinationValue];
+
+		  if (node != nil)
+		    {
+		      /* Per the documentation 10.4/5+ uses NSTreeNode as the return value for
+		       * the contents of this tree node consists of a dictionary with a single
+		       * key of "children".   This is per the tests for this at
+		       * https://github.com/gcasa/NSTreeController_test.  Specifically it returns
+		       * _NSControllerTreeProxy.  The equivalent of that class in GNUstep is
+		       * GSControllerTreeProxy.
+		       */
+		      children = [node mutableChildNodes];
+		      rows = [children count];
+		      item = node;
+		    }
+		}
+	      else
+		{
+		  NSString *childrenKeyPath = [tc childrenKeyPathForNode: item];
 
-      // Ask the delegate for the number of rows for a given item...
-      rows = [_browserDelegate browser: self numberOfChildrenOfItem: item];
+		  if (childrenKeyPath != nil)
+		    {
+		      NSString *countKeyPath = [tc countKeyPathForNode: item];
+
+		      children = [item valueForKeyPath: childrenKeyPath];
+		      if (countKeyPath == nil)
+			{
+			  rows = [children count]; // get the count directly...
+			}
+		      else
+			{
+			  NSNumber *countValue = [item valueForKeyPath: countKeyPath];
+			  rows = [countValue integerValue];
+			}
+		    }
+		}
+
+	      // If the node has children, add them to the column...
+	      if (children != nil)
+		{
+		  [_columnDictionary setObject: children forKey: colNum];
+		}
+	    }
+	}
+      else
+	{
+	  // Ask the delegate for the number of rows for a given item...
+	  rows = [_browserDelegate browser: self numberOfChildrenOfItem: item];
+	}
       cols = 1;
     }
   else if (_passiveDelegate)
@@ -3410,23 +3528,64 @@ - (void) _performLoadOfColumn: (NSInteger)column
   [sc setDocumentView: matrix];
 
   // Loading is different based upon item/passive/active delegate
-  if (_itemBasedDelegate)
+  if (_itemBasedDelegate == YES) //  && item != nil && tc != nil)
     {
-      // Iterate over the children for the item....
-      for (i = 0; i < rows; i++)
+      NSString *childrenKeyPath = [tc childrenKeyPathForNode: item];
+
+      if (childrenKeyPath != nil)
 	{
-	  id aCell = [matrix cellAtRow: i column: 0];
-	  if (![aCell isLoaded])
+	  NSString *leafKeyPath = [tc leafKeyPathForNode: item];
+	  NSString *valueKeyPath = [self _keyPathForValueBinding];
+
+	  // Iterate over the children for the item....
+	  for (i = 0; i < rows; i++)
 	    {
-	      BOOL leaf = YES;
-	      id val = nil;
-
-	      child = [_browserDelegate browser: self child: i ofItem: item];
-	      leaf = [_browserDelegate browser: self isLeafItem: child];
-	      val = [_browserDelegate browser: self objectValueForItem: child];
-	      [aCell setLeaf: leaf];
-	      [aCell setObjectValue: val];
-	      [aCell setLoaded: YES];
+	      id aCell = [matrix cellAtRow: i column: 0];
+	      if (![aCell isLoaded])
+		{
+		  BOOL leaf = YES;
+		  id val = nil;
+		  NSNumber *leafBool = nil;
+
+		  child = [children objectAtIndex: i];
+		  leafBool = [child valueForKeyPath: leafKeyPath];
+		  leaf = [leafBool boolValue];
+
+		  // If a content values binding is present, it uses that key path,
+		  // but if one isn't it uses the description... per documentation.
+		  if (valueKeyPath != nil)
+		    {
+		      val = [child valueForKeyPath: valueKeyPath];
+		    }
+		  else
+		    {
+		      val = [child description]; // per documentation.
+		    }
+
+		  [aCell setLeaf: leaf];
+		  [aCell setObjectValue: val];
+		  [aCell setLoaded: YES];
+		}
+	    }
+	}
+      else
+	{
+	  // Iterate over the children for the item....
+	  for (i = 0; i < rows; i++)
+	    {
+	      id aCell = [matrix cellAtRow: i column: 0];
+	      if (![aCell isLoaded])
+		{
+		  BOOL leaf = YES;
+		  id val = nil;
+
+		  child = [_browserDelegate browser: self child: i ofItem: item];
+		  leaf = [_browserDelegate browser: self isLeafItem: child];
+		  val = [_browserDelegate browser: self objectValueForItem: child];
+		  [aCell setLeaf: leaf];
+		  [aCell setObjectValue: val];
+		  [aCell setLoaded: YES];
+		}
 	    }
 	}
     }
@@ -3592,3 +3751,40 @@ - (void) _themeDidActivate: (NSNotification*)notification
 }
 
 @end
+
+@implementation NSBrowser (GSBindingsPrivate)
+
+/* Private methods to handle bindings */
+
+- (void) setValue: (id)anObject forKey: (NSString*)aKey
+{
+  if ([aKey isEqual: NSContentBinding]
+      || [aKey isEqual: NSContentValuesBinding])
+    {
+      // Reload data
+      _passiveDelegate = NO;
+      _itemBasedDelegate = YES;
+
+      [self loadColumnZero];
+      NSDebugLLog(@"NSBinding", @"Setting browser view content/values to %@", anObject);
+    }
+  else
+    {
+      [super setValue: anObject forKey: aKey];
+    }
+}
+
+- (id) valueForKey: (NSString*)aKey
+{
+  if ([aKey isEqual: NSContentBinding]
+      || [aKey isEqual: NSContentValuesBinding])
+    {
+      return nil;
+    }
+  else
+    {
+      return [super valueForKey: aKey];
+    }
+}
+
+@end