macosx: Implement updateHeaderForTableView in abstract grouping data source

Signed-off-by: Claudio Cambra <developer@claudiocambra.com>

modules/gui/macosx/library/VLCLibraryAbstractGroupingDataSource.h

@@ -24,6 +24,7 @@
 
 #import "library/VLCLibraryCollectionViewDataSource.h"
 #import "library/VLCLibraryMasterDetailViewTableViewDataSource.h"
+#import "library/VLCLibraryGroupHeaderDelegate.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -36,6 +37,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (readwrite, weak) NSCollectionView *collectionView;
 @property (readwrite, weak) NSTableView *masterTableView;
 @property (readwrite, weak) NSTableView *detailTableView;
+@property (readwrite, weak, nullable) id<VLCLibraryGroupHeaderDelegate> headerDelegate;
 
 - (void)reloadData;
 

modules/gui/macosx/library/VLCLibraryAbstractGroupingDataSource.m

@@ -51,6 +51,7 @@
     [self.masterTableView reloadData];
     [self.detailTableView reloadData];
     [self.collectionView reloadData];
+    [self updateHeaderForTableView:self.masterTableView];
 }
 
 - (NSUInteger)indexOfMediaItem:(const int64_t)libraryId inArray:(NSArray const *)array
@@ -105,6 +106,30 @@
     return nil;
 }
 
+- (void)updateHeaderForTableView:(NSTableView *)tableView
+{
+    if (self.headerDelegate == nil) {
+        return;
+    }
+
+    VLCLibraryRepresentedItem *representedItem = nil;
+    NSString *fallbackTitle = nil;
+    NSString *fallbackDetail = nil;
+
+    const NSInteger selectedRow = tableView.selectedRow;
+    if (selectedRow != -1) {
+        const id<VLCMediaLibraryItemProtocol> selectedItem = [self libraryItemAtRow:selectedRow forTableView:tableView];
+        representedItem = [[VLCLibraryRepresentedItem alloc] initWithItem:selectedItem parentType:self.currentParentType];
+        fallbackTitle = selectedItem.displayString;
+        fallbackDetail = selectedItem.primaryDetailString;
+    }
+
+    [self.headerDelegate updateHeaderForTableView:tableView
+                              withRepresentedItem:representedItem
+                                    fallbackTitle:fallbackTitle
+                                   fallbackDetail:fallbackDetail];
+}
+
 - (NSInteger)rowForLibraryItem:(id<VLCMediaLibraryItemProtocol>)libraryItem
 {
     if (libraryItem == nil) {