Squashed commit of the following:

commit c41312ac604526fbfa8eb9c70c26afb5711531ed
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Mon Jun 7 22:55:43 2021 -0400

    replace custom table delegate/datasource with array controller

    required a few tweaks to get the binding correct and equivalent to the hand-rolled version.

    The only advantage is the filtering capability (currently All/Missing)

    Also, refreshing didn't update the status and url if the local file had been deleted.

commit 3aedf237344fa9fbb8225cf3513a27da9647ea07
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Mon Jun 7 21:13:39 2021 -0400

    add toolbar and array controller to filter missing roms, etc.

Ample/Base.lproj/DownloadWindow.xib

@@ -8,8 +8,11 @@
     <objects>
         <customObject id="-2" userLabel="File's Owner" customClass="DownloadWindowController">
             <connections>
+                <outlet property="allFilterButton" destination="Kgj-LP-FsF" id="yub-s9-RVW"/>
+                <outlet property="arrayController" destination="jhO-4z-Qwt" id="GHu-xb-4zU"/>
                 <outlet property="downloadField" destination="sJz-So-jbA" id="WjK-48-FcE"/>
                 <outlet property="formatButton" destination="2Rg-eX-DUq" id="oYo-MG-Sc6"/>
+                <outlet property="missingFilterButton" destination="6c7-tU-3F3" id="89Y-wQ-9pB"/>
                 <outlet property="tableView" destination="FLX-Wt-y53" id="a4O-pk-EAt"/>
                 <outlet property="window" destination="F0z-JX-Cv5" id="gIp-Ho-8D9"/>
             </connections>
@@ -26,7 +29,7 @@
                 <autoresizingMask key="autoresizingMask"/>
                 <subviews>
                     <button verticalHuggingPriority="750" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="rg5-Qf-4Mw">
-                        <rect key="frame" x="324" y="19" width="56" height="23"/>
+                        <rect key="frame" x="324.5" y="19" width="56" height="23"/>
                         <autoresizingMask key="autoresizingMask" flexibleMinX="YES" flexibleMaxY="YES"/>
                         <buttonCell key="cell" type="roundTextured" title="Cancel" bezelStyle="texturedRounded" alignment="center" lineBreakMode="truncatingTail" state="on" borderStyle="border" imageScaling="proportionallyDown" inset="2" id="i6Z-OM-lqE">
                             <behavior key="behavior" pushIn="YES" lightByBackground="YES" lightByGray="YES"/>
@@ -69,26 +72,8 @@
                                             </textFieldCell>
                                             <tableColumnResizingMask key="resizingMask" resizeWithTable="YES"/>
                                             <prototypeCellViews>
-                                                <tableCellView identifier="Cell" focusRingType="none" id="aBv-F5-XWo">
+                                                <tableCellView focusRingType="none" id="onK-6l-2iV">
-                                                    <rect key="frame" x="1" y="1" width="397" height="17"/>
+                                                    <rect key="frame" x="1" y="1" width="397" height="49"/>
-                                                    <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
-                                                    <subviews>
-                                                        <textField verticalHuggingPriority="750" horizontalCompressionResistancePriority="250" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="pWm-hb-BXB">
-                                                            <rect key="frame" x="0.0" y="0.0" width="397" height="17"/>
-                                                            <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMinY="YES"/>
-                                                            <textFieldCell key="cell" lineBreakMode="truncatingTail" sendsActionOnEndEditing="YES" title="Table View Cell" id="p71-gJ-vFV">
-                                                                <font key="font" metaFont="system"/>
-                                                                <color key="textColor" name="controlTextColor" catalog="System" colorSpace="catalog"/>
-                                                                <color key="backgroundColor" name="controlColor" catalog="System" colorSpace="catalog"/>
-                                                            </textFieldCell>
-                                                        </textField>
-                                                    </subviews>
-                                                    <connections>
-                                                        <outlet property="textField" destination="pWm-hb-BXB" id="NNG-rj-AAQ"/>
-                                                    </connections>
-                                                </tableCellView>
-                                                <tableCellView identifier="DownloadCell" focusRingType="none" id="onK-6l-2iV" customClass="DownloadTableCellView">
-                                                    <rect key="frame" x="1" y="20" width="397" height="49"/>
                                                     <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                                                     <subviews>
                                                         <textField verticalHuggingPriority="750" horizontalCompressionResistancePriority="250" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="A44-us-TEl">
@@ -99,10 +84,28 @@
                                                                 <color key="textColor" name="controlTextColor" catalog="System" colorSpace="catalog"/>
                                                                 <color key="backgroundColor" name="controlColor" catalog="System" colorSpace="catalog"/>
                                                             </textFieldCell>
+                                                            <connections>
+                                                                <binding destination="onK-6l-2iV" name="textColor" keyPath="objectValue.titleColor" id="0Qx-rz-DEZ"/>
+                                                                <binding destination="onK-6l-2iV" name="value" keyPath="objectValue.name" id="t1L-kM-AW6">
+                                                                    <dictionary key="options">
+                                                                        <string key="NSMultipleValuesPlaceholder">multiple</string>
+                                                                        <string key="NSNoSelectionPlaceholder">no selection</string>
+                                                                        <string key="NSNotApplicablePlaceholder">n/a</string>
+                                                                        <string key="NSNullPlaceholder">null</string>
+                                                                    </dictionary>
+                                                                </binding>
+                                                            </connections>
                                                         </textField>
                                                         <progressIndicator wantsLayer="YES" fixedFrame="YES" maxValue="100" displayedWhenStopped="NO" indeterminate="YES" controlSize="small" style="spinning" translatesAutoresizingMaskIntoConstraints="NO" id="jBN-UJ-tWi">
                                                             <rect key="frame" x="3" y="29" width="16" height="16"/>
                                                             <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMinY="YES"/>
+                                                            <connections>
+                                                                <binding destination="onK-6l-2iV" name="animate" keyPath="objectValue.task" id="d22-JL-3Z7">
+                                                                    <dictionary key="options">
+                                                                        <string key="NSValueTransformerName">NSIsNotNil</string>
+                                                                    </dictionary>
+                                                                </binding>
+                                                            </connections>
                                                         </progressIndicator>
                                                         <textField verticalHuggingPriority="750" horizontalCompressionResistancePriority="250" fixedFrame="YES" translatesAutoresizingMaskIntoConstraints="NO" id="hfu-hP-QAH">
                                                             <rect key="frame" x="25" y="3" width="371" height="17"/>
@@ -112,20 +115,21 @@
                                                                 <color key="textColor" name="controlTextColor" catalog="System" colorSpace="catalog"/>
                                                                 <color key="backgroundColor" name="controlColor" catalog="System" colorSpace="catalog"/>
                                                             </textFieldCell>
+                                                            <connections>
+                                                                <binding destination="onK-6l-2iV" name="textColor" keyPath="objectValue.descriptionColor" id="KVi-3N-Swm"/>
+                                                                <binding destination="onK-6l-2iV" name="value" keyPath="objectValue.statusDescription" id="yV1-5r-YDh"/>
+                                                            </connections>
                                                         </textField>
                                                     </subviews>
                                                     <connections>
-                                                        <outlet property="activity" destination="jBN-UJ-tWi" id="ZwD-yU-Vne"/>
+                                                        <outlet property="textField" destination="A44-us-TEl" id="ude-er-Gm4"/>
-                                                        <outlet property="statusTextField" destination="hfu-hP-QAH" id="8Hv-BB-kYA"/>
-                                                        <outlet property="textField" destination="A44-us-TEl" id="Ta5-nd-ed1"/>
                                                     </connections>
                                                 </tableCellView>
                                             </prototypeCellViews>
                                         </tableColumn>
                                     </tableColumns>
                                     <connections>
-                                        <outlet property="dataSource" destination="-2" id="Ghf-k9-bRK"/>
+                                        <binding destination="jhO-4z-Qwt" name="content" keyPath="arrangedObjects" id="2av-gV-V4K"/>
-                                        <outlet property="delegate" destination="-2" id="rpR-0W-4Nu"/>
                                         <outlet property="menu" destination="RJM-21-hjO" id="xpL-0n-1jm"/>
                                     </connections>
                                 </tableView>
@@ -239,6 +243,44 @@
                     </popUpButton>
                 </subviews>
             </view>
+            <toolbar key="toolbar" implicitIdentifier="B60021E6-BFBC-44E6-97DC-120AA9FD3269" autosavesConfiguration="NO" allowsUserCustomization="NO" displayMode="iconOnly" sizeMode="regular" id="kpz-W4-xgh">
+                <allowedToolbarItems>
+                    <toolbarItem implicitItemIdentifier="NSToolbarSpaceItem" id="tbY-ts-Irb"/>
+                    <toolbarItem implicitItemIdentifier="NSToolbarFlexibleSpaceItem" id="3Kc-zG-IdN"/>
+                    <toolbarItem implicitItemIdentifier="BD743A15-0B61-48FF-9EED-FD8D57EF8459" label="All" paletteLabel="All" tag="1" sizingBehavior="auto" id="Jj0-n8-I5a">
+                        <nil key="toolTip"/>
+                        <button key="view" verticalHuggingPriority="750" tag="1" id="Kgj-LP-FsF">
+                            <rect key="frame" x="0.0" y="14" width="74" height="20"/>
+                            <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMinY="YES"/>
+                            <buttonCell key="cell" type="recessed" title="All" bezelStyle="recessed" alignment="center" state="on" borderStyle="border" imageScaling="proportionallyDown" inset="2" id="9s7-S1-hW1">
+                                <behavior key="behavior" lightByBackground="YES" lightByGray="YES" changeBackground="YES" changeGray="YES"/>
+                                <font key="font" metaFont="systemBold" size="12"/>
+                            </buttonCell>
+                            <connections>
+                                <action selector="filterButton:" target="-2" id="gTc-Ul-FYR"/>
+                            </connections>
+                        </button>
+                    </toolbarItem>
+                    <toolbarItem implicitItemIdentifier="5B013840-E582-4568-8448-DDD7EE1E5AE2" label="Missing" paletteLabel="Missing" tag="2" sizingBehavior="auto" id="GV4-aX-5Ox">
+                        <nil key="toolTip"/>
+                        <button key="view" verticalHuggingPriority="750" tag="2" id="6c7-tU-3F3">
+                            <rect key="frame" x="0.0" y="14" width="74" height="20"/>
+                            <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMinY="YES"/>
+                            <buttonCell key="cell" type="recessed" title="Missing" bezelStyle="recessed" alignment="center" borderStyle="border" imageScaling="proportionallyDown" inset="2" id="ui2-dz-IZj">
+                                <behavior key="behavior" lightByBackground="YES" lightByGray="YES" changeBackground="YES" changeGray="YES"/>
+                                <font key="font" metaFont="systemBold" size="12"/>
+                            </buttonCell>
+                            <connections>
+                                <action selector="filterButton:" target="-2" id="R6W-hU-oqL"/>
+                            </connections>
+                        </button>
+                    </toolbarItem>
+                </allowedToolbarItems>
+                <defaultToolbarItems>
+                    <toolbarItem reference="Jj0-n8-I5a"/>
+                    <toolbarItem reference="GV4-aX-5Ox"/>
+                </defaultToolbarItems>
+            </toolbar>
             <connections>
                 <outlet property="delegate" destination="-2" id="0bl-1N-AYu"/>
             </connections>
@@ -270,6 +312,7 @@
             </connections>
             <point key="canvasLocation" x="-348" y="164"/>
         </menu>
+        <arrayController objectClassName="DownloadItem" editable="NO" preservesSelection="NO" selectsInsertedObjects="NO" avoidsEmptySelection="NO" clearsFilterPredicateOnInsertion="NO" automaticallyRearrangesObjects="YES" id="jhO-4z-Qwt" customClass="DownloadItemArrayController"/>
         <userDefaultsController representsSharedInstance="YES" id="721-9N-Bma"/>
     </objects>
     <resources>

Ample/DownloadWindowController.h

@@ -26,17 +26,9 @@ NS_ASSUME_NONNULL_BEGIN
 @interface DownloadWindowController (URL) <NSURLSessionTaskDelegate, NSURLSessionDownloadDelegate>
 @end
 
-@interface DownloadWindowController (Table) <NSTableViewDelegate, NSTableViewDataSource>
-@end
 
 @interface DownloadWindowController (Menu) <NSMenuDelegate, NSMenuItemValidation>
 
 @end
 
-
-@interface DownloadTableCellView : NSTableCellView
-@property (weak) IBOutlet NSTextField *statusTextField;
-@property (weak) IBOutlet NSProgressIndicator *activity;
-@end
-
 NS_ASSUME_NONNULL_END

Ample/DownloadWindowController.m

@@ -90,6 +90,9 @@ enum {
 @property NSUInteger status;
 @property NSUInteger index;
 
+@property (readonly) NSColor *titleColor;
+@property (readonly) NSColor *descriptionColor;
+
 
 -(void)cancelDownload;
 -(void)beginDownloadWithTask:(NSURLSessionDownloadTask *)task;
@@ -98,6 +101,21 @@ enum {
 @end
 
 
+@interface DownloadItemArrayController : NSArrayController
+
+@property(readonly, copy) NSArray<NSString *> *automaticRearrangementKeyPaths;
+
+@end
+
+@implementation DownloadItemArrayController
+
+-(NSArray<NSString *> *)automaticRearrangementKeyPaths {
+    return @[@"localURL"]; // , @"error", @"task", @"statusDescription"];
+}
+
+
+@end
+
 
 @interface DownloadWindowController ()
 @property (weak) IBOutlet NSTableView *tableView;
@@ -105,6 +123,14 @@ enum {
 @property (weak) IBOutlet NSTextField *downloadField;
 @property NSString *downloadExtension;
 
+/* filter buttons */
+@property (weak) IBOutlet NSButton *allFilterButton;
+@property (weak) IBOutlet NSButton *missingFilterButton;
+
+@property (strong) IBOutlet NSArrayController *arrayController;
+
+
+
 @end
 
 @implementation DownloadWindowController {
@@ -117,6 +143,8 @@ enum {
     NSURLSession *_session;
     NSMutableDictionary *_taskIndex;
     NSUserDefaults *_defaults;
+    
+    NSArray<NSButton *> *_filterButtons;
 }
 
 +(instancetype)sharedInstance {
@@ -166,6 +194,12 @@ enum {
     [window setRestorationClass: [self class]];
 #endif
     
+    _filterButtons = @[
+        _allFilterButton,
+        _missingFilterButton
+    ];
+    
+
     // Implement this method to handle any initialization after your window controller's window has been loaded from its nib file.
 
     NSError *error = nil;
@@ -217,6 +251,7 @@ enum {
     }
     _items = tmp;
     [self refreshROMs: nil];
+    [_arrayController setContent: _items];
  
     //[_tableView reloadData];
     NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
@@ -299,8 +334,10 @@ enum {
 -(DownloadItem *)clickedItem {
     NSInteger row = [_tableView clickedRow];
     if (row < 0 || row >= [_items count]) return nil;
-    return [_items objectAtIndex: row];
+    return [[_arrayController arrangedObjects] objectAtIndex: row];
+    //return [_items objectAtIndex: row];
 }
+#if 0
 -(void)redrawRow: (NSUInteger)row {
     
     //NSRect r = [_tableView rectOfRow: row];
@@ -311,7 +348,7 @@ enum {
     
     [_tableView reloadDataForRowIndexes: rIx columnIndexes: cIx];
 }
-
+#endif
 
 -(void)initializeExtensionMenu {
     
@@ -350,7 +387,7 @@ enum {
     [self setCurrentCount: 0];
     [self setActive: NO];
 
-    [_tableView reloadData];
+    //[_tableView reloadData];
     //[_tableView setNeedsDisplay: YES]; // doesn't work...
 }
 
@@ -368,7 +405,7 @@ enum {
     
     if (delta) {
         [self setActive: YES];
-        [_tableView reloadData];
+        //[_tableView reloadData];
     }
 }
 - (IBAction)showRomFolder:(id)sender {
@@ -399,11 +436,10 @@ enum {
             [item setLocalURL: [NSURL fileURLWithPath: path]];
             continue;
         }
-
+        
-
+        [item setStatus: ItemMissing];
+        [item setLocalURL: nil];
     }
-    // only needed if items aren't bound.
-    [_tableView reloadData];
 }
 
 - (IBAction)showInFinder:(id)sender {
@@ -422,14 +458,14 @@ enum {
 
     [self downloadItem: item];
     [self setActive: YES];
-    [self redrawRow: [item index]];
+    //[self redrawRow: [item index]];
 }
 - (IBAction)cancel:(id)sender {
     DownloadItem *item = [self clickedItem];
     if (!item) return;
 
     [item cancelDownload];
-    [self redrawRow: [item index]];
+    //[self redrawRow: [item index]];
 }
 
 // binding screws up with placeholder.
@@ -449,6 +485,36 @@ enum {
     [_defaults setValue: _downloadExtension forKey: kDownloadExtension];
 }
 
+
+- (IBAction)filterButton:(id)sender {
+
+    NSPredicate *p = nil;
+    NSUInteger tag = [sender tag];
+    [sender setState: NSControlStateValueOn];
+
+
+
+    for (NSButton *b in _filterButtons) {
+        if (b != sender) [b setState: NSControlStateValueOff];
+    }
+    switch (tag) {
+        case 1: // all
+        default:
+            [_arrayController setFilterPredicate: nil];
+            break;
+        case 2: // missing.
+            p = [NSPredicate predicateWithBlock: ^BOOL(DownloadItem *item, NSDictionary *bindings){
+                NSURL *localURL = [item localURL];
+                return localURL == nil;
+            }];
+
+            [_arrayController setFilterPredicate: p];
+            break;
+    }
+}
+
+
+
 #pragma mark - NSURLSessionDelegate
 
 static NSInteger TaskStatusCode(NSURLSessionTask *task) {
@@ -495,9 +561,9 @@ static NSInteger TaskStatusCode(NSURLSessionTask *task) {
         
         if (item) {
             [item completeWithError: error];
-            NSUInteger row = [item index];
+            //NSUInteger row = [item index];
             
-            [self redrawRow: row];
+            //[self redrawRow: row];
         }
     });
     
@@ -536,91 +602,46 @@ static NSInteger TaskStatusCode(NSURLSessionTask *task) {
 
 @end
 
-@implementation DownloadWindowController (Table)
-
-- (NSInteger)numberOfRowsInTableView:(NSTableView *)tableView {
-    return [_items count];
-}
-
-- (id)tableView:(NSTableView *)tableView objectValueForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row {
-    
-    return [_items objectAtIndex: row];
-}
 
 
-- (NSView *)tableView:(NSTableView *)tableView viewForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row {
- 
-    DownloadItem *item = [_items objectAtIndex: row];
-    DownloadTableCellView *v = [tableView makeViewWithIdentifier: @"DownloadCell" owner: self];
-    
-    NSTextField *tf;
-    NSColor *redColor = [NSColor systemRedColor];
-    
-    tf = [v textField];
-    [[v textField] setObjectValue: [item name]];
-    
-    if ([item localURL]) {
-        [tf setTextColor: nil];
-    } else {
-        [tf setTextColor: redColor];
-    }
-    
-    tf = [v statusTextField];
-    [tf setObjectValue: [item statusDescription]];
-    if ([item error]) {
-        [tf setTextColor: redColor];
-    } else {
-        [tf setTextColor: nil];
-        //if ([tableView isRowSelected: row]){
-            //[tf setTextColor: [NSColor whiteColor]];
-        //}
-    }
-
-    if ([item task]) {
-        [[v activity] startAnimation: nil];
-    } else {
-        [[v activity] stopAnimation: nil];
-    }
-    
-    
-    return v;
-}
-
-
-@end
-
-
-@implementation DownloadTableCellView
-
-@end
 
 @implementation DownloadItem
 
 -(void)beginDownloadWithTask:(NSURLSessionDownloadTask *)task {
-    _task = task;
+    [self setTask: task];
-    _error = nil;
+    [self setError: nil];
-    if (task) _status = ItemDownloading;
+    if (task) [self setStatus: ItemDownloading];
 }
 
 -(void)cancelDownload {
     if (!_task) return;
+
     [_task cancel];
-    _task = nil;
+    [self setTask: nil];
-    _status = ItemCanceled;
+    [self setStatus: ItemCanceled];
 }
 
 -(void)completeWithError: (NSError *)error {
-    _task = nil;
+    [self setTask: nil];
     if (error) {
-        _error = error;
+        [self setError: error];
-        _status = ItemError;
+        [self setStatus: ItemError];
     } else {
         // what if there was an error moving it?
-        _error = nil;
+        [self setError: nil];
-        _status = ItemDownloaded;
+        [self setStatus: ItemDownloaded];
     }
 }
 
+#if 0
+// in practice, error and status set concurrently.
++(NSSet *)keyPathsForValuesAffectingStatus {
+    static NSSet *set = nil;
+    if (!set) set = [NSSet setWithObjects: @"error", nil];
+    return set;
+}
+#endif
+
 -(NSString *)statusDescription {
 
     static NSString *Names[] = {
@@ -637,6 +658,19 @@ static NSInteger TaskStatusCode(NSURLSessionTask *task) {
     return Names[_status];
 }
 
++(NSSet *)keyPathsForValuesAffectingTitleColor {
+    return [NSSet setWithObject: @"localURL"];
+}
+-(NSColor *)titleColor {
+    return _localURL ? nil : [NSColor systemRedColor];
+}
++(NSSet *)keyPathsForValuesAffectingDescriptionColor {
+    return [NSSet setWithObject: @"error"];
+}
+-(NSColor *)descriptionColor {
+    return _error ? [NSColor systemRedColor] : nil;
+}
+
 @end
 
 
@@ -655,7 +689,7 @@ enum {
 
     NSInteger row = [_tableView clickedRow];
     if (row < 0) return NO;
-    DownloadItem *item = [_items objectAtIndex: row];
+    DownloadItem *item = [[_arrayController arrangedObjects] objectAtIndex: row]; //[_items objectAtIndex: row];
     
     NSUInteger status = [item status];
     switch([menuItem tag]) {