added files via upload

Tweaks/FLEX/Core/Controllers/FLEXFilteringTableViewController.h

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+//
+//  FLEXFilteringTableViewController.h
+//  FLEX
+//
+//  Created by Tanner on 3/9/20.
+//  Copyright © 2020 FLEX Team. All rights reserved.
+//
+
+#import "FLEXTableViewController.h"
+
+#pragma mark - FLEXTableViewFiltering
+@protocol FLEXTableViewFiltering <FLEXSearchResultsUpdating>
+
+/// An array of visible, "filtered" sections. For example,
+/// if you have 3 sections in \c allSections and the user searches
+/// for something that matches rows in only one section, then
+/// this property would only contain that on matching section.
+@property (nonatomic, copy) NSArray<FLEXTableViewSection *> *sections;
+/// An array of all possible sections. Empty sections are to be removed
+/// and the resulting array stored in the \c section property. Setting
+/// this property should immediately set \c sections to \c nonemptySections 
+///
+/// Do not manually initialize this property, it will be
+/// initialized for you using the result of \c makeSections.
+@property (nonatomic, copy) NSArray<FLEXTableViewSection *> *allSections;
+
+/// This computed property should filter \c allSections for assignment to \c sections
+@property (nonatomic, readonly, copy) NSArray<FLEXTableViewSection *> *nonemptySections;
+
+/// This should be able to re-initialize \c allSections
+- (NSArray<FLEXTableViewSection *> *)makeSections;
+
+@end
+
+
+#pragma mark - FLEXFilteringTableViewController
+/// A table view which implements \c UITableView* methods using arrays of
+/// \c FLEXTableViewSection objects provied by a special delegate.
+@interface FLEXFilteringTableViewController : FLEXTableViewController <FLEXTableViewFiltering>
+
+/// Stores the current search query.
+@property (nonatomic, copy) NSString *filterText;
+
+/// This property is set to \c self by default.
+///
+/// This property is used to power almost all of the table view's data source
+/// and delegate methods automatically, including row and section filtering
+/// when the user searches, 3D Touch context menus, row selection, etc.
+///
+/// Setting this property will also set \c searchDelegate to that object.
+@property (nonatomic, weak) id<FLEXTableViewFiltering> filterDelegate;
+
+/// Defaults to \c NO. If enabled, all filtering will be done by calling
+/// \c onBackgroundQueue:thenOnMainQueue: with the UI updated on the main queue.
+@property (nonatomic) BOOL filterInBackground;
+
+/// Defaults to \c NO. If enabled, one • will be supplied as an index title for each section.
+@property (nonatomic) BOOL wantsSectionIndexTitles;
+
+/// Recalculates the non-empty sections and reloads the table view.
+///
+/// Subclasses may override to perform additional reloading logic,
+/// such as calling \c -reloadSections if needed. Be sure to call
+/// \c super after any logic that would affect the appearance of 
+/// the table view, since the table view is reloaded last.
+///
+/// Called at the end of this class's implementation of \c updateSearchResults:
+- (void)reloadData;
+
+/// Invoke this method to call \c -reloadData on each section
+/// in \c self.filterDelegate.allSections.
+- (void)reloadSections;
+
+#pragma mark FLEXTableViewFiltering
+
+@property (nonatomic, copy) NSArray<FLEXTableViewSection *> *sections;
+@property (nonatomic, copy) NSArray<FLEXTableViewSection *> *allSections;
+
+/// Subclasses can override to hide specific sections under certain conditions
+/// if using \c self as the \c filterDelegate, as is the default.
+///
+/// For example, the object explorer hides the description section when searching.
+@property (nonatomic, readonly, copy) NSArray<FLEXTableViewSection *> *nonemptySections;
+
+/// If using \c self as the \c filterDelegate, as is the default,
+/// subclasses should override to provide the sections for the table view.
+- (NSArray<FLEXTableViewSection *> *)makeSections;
+
+@end

Tweaks/FLEX/Core/Controllers/FLEXFilteringTableViewController.m

@@ -0,0 +1,209 @@
+//
+//  FLEXFilteringTableViewController.m
+//  FLEX
+//
+//  Created by Tanner on 3/9/20.
+//  Copyright © 2020 FLEX Team. All rights reserved.
+//
+
+#import "FLEXFilteringTableViewController.h"
+#import "FLEXTableViewSection.h"
+#import "NSArray+FLEX.h"
+#import "FLEXMacros.h"
+
+@interface FLEXFilteringTableViewController ()
+
+@end
+
+@implementation FLEXFilteringTableViewController
+@synthesize allSections = _allSections;
+
+#pragma mark - View controller lifecycle
+
+- (void)loadView {
+    [super loadView];
+    
+    if (!self.filterDelegate) {
+        self.filterDelegate = self;
+    } else {
+        [self _registerCellsForReuse];
+    }
+}
+
+- (void)_registerCellsForReuse {
+    for (FLEXTableViewSection *section in self.filterDelegate.allSections) {
+        if (section.cellRegistrationMapping) {
+            [self.tableView registerCells:section.cellRegistrationMapping];
+        }
+    }
+}
+
+
+#pragma mark - Public
+
+- (void)setFilterDelegate:(id<FLEXTableViewFiltering>)filterDelegate {
+    _filterDelegate = filterDelegate;
+    filterDelegate.allSections = [filterDelegate makeSections];
+    
+    if (self.isViewLoaded) {
+        [self _registerCellsForReuse];
+    }
+}
+
+- (void)reloadData {
+    [self reloadData:self.nonemptySections];
+}
+
+- (void)reloadData:(NSArray *)nonemptySections {
+    // Recalculate displayed sections
+    self.filterDelegate.sections = nonemptySections;
+
+    // Refresh table view
+    if (self.isViewLoaded) {
+        [self.tableView reloadData];
+    }
+}
+
+- (void)reloadSections {
+    for (FLEXTableViewSection *section in self.filterDelegate.allSections) {
+        [section reloadData];
+    }
+}
+
+
+#pragma mark - Search
+
+- (void)updateSearchResults:(NSString *)newText {
+    NSArray *(^filter)(void) = ^NSArray *{
+        self.filterText = newText;
+
+        // Sections will adjust data based on this property
+        for (FLEXTableViewSection *section in self.filterDelegate.allSections) {
+            section.filterText = newText;
+        }
+        
+        return nil;
+    };
+    
+    if (self.filterInBackground) {
+        [self onBackgroundQueue:filter thenOnMainQueue:^(NSArray *unused) {
+            if ([self.searchText isEqualToString:newText]) {
+                [self reloadData];
+            }
+        }];
+    } else {
+        filter();
+        [self reloadData];
+    }
+}
+
+
+#pragma mark Filtering
+
+- (NSArray<FLEXTableViewSection *> *)nonemptySections {
+    return [self.filterDelegate.allSections flex_filtered:^BOOL(FLEXTableViewSection *section, NSUInteger idx) {
+        return section.numberOfRows > 0;
+    }];
+}
+
+- (NSArray<FLEXTableViewSection *> *)makeSections {
+    return @[];
+}
+
+- (void)setAllSections:(NSArray<FLEXTableViewSection *> *)allSections {
+    _allSections = allSections.copy;
+    // Only display nonempty sections
+    self.sections = self.nonemptySections;
+}
+
+- (void)setSections:(NSArray<FLEXTableViewSection *> *)sections {
+    // Allow sections to reload a portion of the table view at will
+    [sections enumerateObjectsUsingBlock:^(FLEXTableViewSection *s, NSUInteger idx, BOOL *stop) {
+        [s setTable:self.tableView section:idx];
+    }];
+    _sections = sections.copy;
+}
+
+
+#pragma mark - UITableViewDataSource
+
+- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
+    return self.filterDelegate.sections.count;
+}
+
+- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
+    return self.filterDelegate.sections[section].numberOfRows;
+}
+
+- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
+    return self.filterDelegate.sections[section].title;
+}
+
+- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
+    NSString *reuse = [self.filterDelegate.sections[indexPath.section] reuseIdentifierForRow:indexPath.row];
+    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:reuse forIndexPath:indexPath];
+    [self.filterDelegate.sections[indexPath.section] configureCell:cell forRow:indexPath.row];
+    return cell;
+}
+
+- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
+    return UITableViewAutomaticDimension;
+}
+
+- (NSArray<NSString *> *)sectionIndexTitlesForTableView:(UITableView *)tableView {
+    if (self.wantsSectionIndexTitles) {
+        return [NSArray flex_forEachUpTo:self.filterDelegate.sections.count map:^id(NSUInteger i) {
+            return @"⦁";
+        }];
+    }
+    
+    return nil;
+}
+
+
+#pragma mark - UITableViewDelegate
+
+- (BOOL)tableView:(UITableView *)tableView shouldHighlightRowAtIndexPath:(NSIndexPath *)indexPath {
+    return [self.filterDelegate.sections[indexPath.section] canSelectRow:indexPath.row];
+}
+
+- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
+    FLEXTableViewSection *section = self.filterDelegate.sections[indexPath.section];
+
+    void (^action)(UIViewController *) = [section didSelectRowAction:indexPath.row];
+    UIViewController *details = [section viewControllerToPushForRow:indexPath.row];
+
+    if (action) {
+        action(self);
+        [tableView deselectRowAtIndexPath:indexPath animated:YES];
+    } else if (details) {
+        [self.navigationController pushViewController:details animated:YES];
+    } else {
+        [NSException raise:NSInternalInconsistencyException
+                    format:@"Row is selectable but has no action or view controller"];
+    }
+}
+
+- (void)tableView:(UITableView *)tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath {
+    [self.filterDelegate.sections[indexPath.section] didPressInfoButtonAction:indexPath.row](self);
+}
+
+- (UIContextMenuConfiguration *)tableView:(UITableView *)tableView contextMenuConfigurationForRowAtIndexPath:(NSIndexPath *)indexPath point:(CGPoint)point __IOS_AVAILABLE(13.0) {
+    FLEXTableViewSection *section = self.filterDelegate.sections[indexPath.section];
+    NSString *title = [section menuTitleForRow:indexPath.row];
+    NSArray<UIMenuElement *> *menuItems = [section menuItemsForRow:indexPath.row sender:self];
+    
+    if (menuItems.count) {
+        return [UIContextMenuConfiguration
+            configurationWithIdentifier:nil
+            previewProvider:nil
+            actionProvider:^UIMenu *(NSArray<UIMenuElement *> *suggestedActions) {
+                return [UIMenu menuWithTitle:title children:menuItems];
+            }
+        ];
+    }
+    
+    return nil;
+}
+
+@end

Tweaks/FLEX/Core/Controllers/FLEXNavigationController.h

@@ -0,0 +1,19 @@
+//
+//  FLEXNavigationController.h
+//  FLEX
+//
+//  Created by Tanner on 1/30/20.
+//  Copyright © 2020 FLEX Team. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface FLEXNavigationController : UINavigationController
+
++ (instancetype)withRootViewController:(UIViewController *)rootVC;
+
+@end
+
+NS_ASSUME_NONNULL_END

Tweaks/FLEX/Core/Controllers/FLEXNavigationController.m

@@ -0,0 +1,196 @@
+//
+//  FLEXNavigationController.m
+//  FLEX
+//
+//  Created by Tanner on 1/30/20.
+//  Copyright © 2020 FLEX Team. All rights reserved.
+//
+
+#import "FLEXNavigationController.h"
+#import "FLEXExplorerViewController.h"
+#import "FLEXTabList.h"
+
+@interface UINavigationController (Private) <UIGestureRecognizerDelegate>
+- (void)_gestureRecognizedInteractiveHide:(UIGestureRecognizer *)sender;
+@end
+@interface UIPanGestureRecognizer (Private)
+- (void)_setDelegate:(id)delegate;
+@end
+
+@interface FLEXNavigationController ()
+@property (nonatomic, readonly) BOOL toolbarWasHidden;
+@property (nonatomic) BOOL waitingToAddTab;
+@property (nonatomic, readonly) BOOL canShowToolbar;
+@property (nonatomic) BOOL didSetupPendingDismissButtons;
+@property (nonatomic) UISwipeGestureRecognizer *navigationBarSwipeGesture;
+@end
+
+@implementation FLEXNavigationController
+
++ (instancetype)withRootViewController:(UIViewController *)rootVC {
+    return [[self alloc] initWithRootViewController:rootVC];
+}
+
+- (void)viewDidLoad {
+    [super viewDidLoad];
+    
+    self.waitingToAddTab = YES;
+    
+    // Add gesture to reveal toolbar if hidden
+    UITapGestureRecognizer *navbarTapGesture = [[UITapGestureRecognizer alloc]
+        initWithTarget:self action:@selector(handleNavigationBarTap:)
+    ];
+    
+    // Don't cancel touches to work around bug on versions of iOS prior to 13
+    navbarTapGesture.cancelsTouchesInView = NO;
+    [self.navigationBar addGestureRecognizer:navbarTapGesture];
+    
+    // Add gesture to dismiss if not presented with a sheet style
+    if (@available(iOS 13, *)) {
+        switch (self.modalPresentationStyle) {
+            case UIModalPresentationAutomatic:
+            case UIModalPresentationPageSheet:
+            case UIModalPresentationFormSheet:
+                break;
+                
+            default:
+                [self addNavigationBarSwipeGesture];
+                break;
+        }
+    } else {
+        [self addNavigationBarSwipeGesture];
+    }
+}
+
+- (void)viewWillAppear:(BOOL)animated {
+    [super viewWillAppear:animated];
+    
+    if (self.beingPresented && !self.didSetupPendingDismissButtons) {
+        for (UIViewController *vc in self.viewControllers) {
+            [self addNavigationBarItemsToViewController:vc.navigationItem];
+        }
+        
+        self.didSetupPendingDismissButtons = YES;
+    }
+}
+
+- (void)viewDidAppear:(BOOL)animated {
+    [super viewDidAppear:animated];
+    
+    if (self.waitingToAddTab) {
+        // Only add new tab if we're presented properly
+        if ([self.presentingViewController isKindOfClass:[FLEXExplorerViewController class]]) {
+            // New navigation controllers always add themselves as new tabs,
+            // tabs are closed by FLEXExplorerViewController
+            [FLEXTabList.sharedList addTab:self];
+            self.waitingToAddTab = NO;
+        }
+    }
+}
+
+- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated {
+    [super pushViewController:viewController animated:animated];
+    [self addNavigationBarItemsToViewController:viewController.navigationItem];
+}
+
+- (void)dismissAnimated {
+    // Tabs are only closed if the done button is pressed; this
+    // allows you to leave a tab open by dragging down to dismiss
+    if ([self.presentingViewController isKindOfClass:[FLEXExplorerViewController class]]) {
+        [FLEXTabList.sharedList closeTab:self];        
+    }
+    
+    [self.presentingViewController dismissViewControllerAnimated:YES completion:nil];
+}
+
+- (BOOL)canShowToolbar {
+    return self.topViewController.toolbarItems.count > 0;
+}
+
+- (void)addNavigationBarItemsToViewController:(UINavigationItem *)navigationItem {
+    if (!self.presentingViewController) {
+        return;
+    }
+    
+    // Check if a done item already exists
+    for (UIBarButtonItem *item in navigationItem.rightBarButtonItems) {
+        if (item.style == UIBarButtonItemStyleDone) {
+            return;
+        }
+    }
+    
+    // Give root view controllers a Done button if it does not already have one
+    UIBarButtonItem *done = [[UIBarButtonItem alloc]
+        initWithBarButtonSystemItem:UIBarButtonSystemItemDone
+        target:self
+        action:@selector(dismissAnimated)
+    ];
+    
+    // Prepend the button if other buttons exist already
+    NSArray *existingItems = navigationItem.rightBarButtonItems;
+    if (existingItems.count) {
+        navigationItem.rightBarButtonItems = [@[done] arrayByAddingObjectsFromArray:existingItems];
+    } else {
+        navigationItem.rightBarButtonItem = done;
+    }
+    
+    // Keeps us from calling this method again on
+    // the same view controllers in -viewWillAppear:
+    self.didSetupPendingDismissButtons = YES;
+}
+
+- (void)addNavigationBarSwipeGesture {
+    UISwipeGestureRecognizer *swipe = [[UISwipeGestureRecognizer alloc]
+        initWithTarget:self action:@selector(handleNavigationBarSwipe:)
+    ];
+    swipe.direction = UISwipeGestureRecognizerDirectionDown;
+    swipe.delegate = self;
+    self.navigationBarSwipeGesture = swipe;
+    [self.navigationBar addGestureRecognizer:swipe];
+}
+
+- (void)handleNavigationBarSwipe:(UISwipeGestureRecognizer *)sender {
+    if (sender.state == UIGestureRecognizerStateRecognized) {
+        [self.presentingViewController dismissViewControllerAnimated:YES completion:nil];
+    }
+}
+     
+- (void)handleNavigationBarTap:(UIGestureRecognizer *)sender {
+    // Don't reveal the toolbar if we were just tapping a button
+    CGPoint location = [sender locationInView:self.navigationBar];
+    UIView *hitView = [self.navigationBar hitTest:location withEvent:nil];
+    if ([hitView isKindOfClass:[UIControl class]]) {
+        return;
+    }
+
+    if (sender.state == UIGestureRecognizerStateRecognized) {
+        if (self.toolbarHidden && self.canShowToolbar) {
+            [self setToolbarHidden:NO animated:YES];
+        }
+    }
+}
+
+- (BOOL)gestureRecognizer:(UIGestureRecognizer *)g1 shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)g2 {
+    if (g1 == self.navigationBarSwipeGesture && g2 == self.barHideOnSwipeGestureRecognizer) {
+        return YES;
+    }
+    
+    return NO;
+}
+
+- (void)_gestureRecognizedInteractiveHide:(UIPanGestureRecognizer *)sender {
+    if (sender.state == UIGestureRecognizerStateRecognized) {
+        BOOL show = self.canShowToolbar;
+        CGFloat yTranslation = [sender translationInView:self.view].y;
+        CGFloat yVelocity = [sender velocityInView:self.view].y;
+        if (yVelocity > 2000) {
+            [self setToolbarHidden:YES animated:YES];
+        } else if (show && yTranslation > 20 && yVelocity > 250) {
+            [self setToolbarHidden:NO animated:YES];
+        } else if (yTranslation < -20) {
+            [self setToolbarHidden:YES animated:YES];
+        }
+    }
+}
+
+@end

Tweaks/FLEX/Core/Controllers/FLEXTableViewController.h

@@ -0,0 +1,153 @@
+//
+//  FLEXTableViewController.h
+//  FLEX
+//
+//  Created by Tanner on 7/5/19.
+//  Copyright © 2020 FLEX Team. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+#import "FLEXTableView.h"
+@class FLEXScopeCarousel, FLEXWindow, FLEXTableViewSection;
+
+typedef CGFloat FLEXDebounceInterval;
+/// No delay, all events delivered
+extern CGFloat const kFLEXDebounceInstant;
+/// Small delay which makes UI seem smoother by avoiding rapid events
+extern CGFloat const kFLEXDebounceFast;
+/// Slower than Fast, faster than ExpensiveIO
+extern CGFloat const kFLEXDebounceForAsyncSearch;
+/// The least frequent, at just over once per second; for I/O or other expensive operations
+extern CGFloat const kFLEXDebounceForExpensiveIO;
+
+@protocol FLEXSearchResultsUpdating <NSObject>
+/// A method to handle search query update events.
+///
+/// \c searchBarDebounceInterval is used to reduce the frequency at which this
+/// method is called. This method is also called when the search bar becomes
+/// the first responder, and when the selected search bar scope index changes.
+- (void)updateSearchResults:(NSString *)newText;
+@end
+
+@interface FLEXTableViewController : UITableViewController <
+    UISearchResultsUpdating, UISearchControllerDelegate, UISearchBarDelegate
+>
+
+/// A grouped table view. Inset on iOS 13.
+///
+/// Simply calls into \c initWithStyle:
+- (id)init;
+
+/// Subclasses may override to configure the controller before \c viewDidLoad:
+- (id)initWithStyle:(UITableViewStyle)style;
+
+@property (nonatomic) FLEXTableView *tableView;
+
+/// If your subclass conforms to \c FLEXSearchResultsUpdating
+/// then this property is assigned to \c self automatically.
+///
+/// Setting \c filterDelegate will also set this property to that object.
+@property (nonatomic, weak) id<FLEXSearchResultsUpdating> searchDelegate;
+
+/// Defaults to NO.
+///
+/// Setting this to YES will initialize the carousel and the view.
+@property (nonatomic) BOOL showsCarousel;
+/// A horizontally scrolling list with functionality similar to
+/// that of a search bar's scope bar. You'd want to use this when
+/// you have potentially more than 4 scope options.
+@property (nonatomic) FLEXScopeCarousel *carousel;
+
+/// Defaults to NO.
+///
+/// Setting this to YES will initialize searchController and the view.
+@property (nonatomic) BOOL showsSearchBar;
+/// Defaults to NO.
+///
+/// Setting this to YES will make the search bar appear whenever the view appears.
+/// Otherwise, iOS will only show the search bar when you scroll up.
+@property (nonatomic) BOOL showSearchBarInitially;
+/// Defaults to NO.
+///
+/// Setting this to YES will make the search bar activate whenever the view appears.
+@property (nonatomic) BOOL activatesSearchBarAutomatically;
+
+/// nil unless showsSearchBar is set to YES.
+///
+/// self is used as the default search results updater and delegate.
+/// The search bar will not dim the background or hide the navigation bar by default.
+/// On iOS 11 and up, the search bar will appear in the navigation bar below the title.
+@property (nonatomic) UISearchController *searchController;
+/// Used to initialize the search controller. Defaults to nil.
+@property (nonatomic) UIViewController *searchResultsController;
+/// Defaults to "Fast"
+///
+/// Determines how often search bar results will be "debounced."
+/// Empty query events are always sent instantly. Query events will
+/// be sent when the user has not changed the query for this interval.
+@property (nonatomic) FLEXDebounceInterval searchBarDebounceInterval;
+/// Whether the search bar stays at the top of the view while scrolling.
+///
+/// Calls into self.navigationItem.hidesSearchBarWhenScrolling.
+/// Do not change self.navigationItem.hidesSearchBarWhenScrolling directly,
+/// or it will not be respsected. Use this instead.
+/// Defaults to NO.
+@property (nonatomic) BOOL pinSearchBar;
+/// By default, we will show the search bar's cancel button when
+/// search becomes active and hide it when search is dismissed.
+///
+/// Do not set the showsCancelButton property on the searchController's
+/// searchBar manually. Set this property after turning on showsSearchBar.
+///
+/// Does nothing pre-iOS 13, safe to call on any version.
+@property (nonatomic) BOOL automaticallyShowsSearchBarCancelButton;
+
+/// If using the scope bar, self.searchController.searchBar.selectedScopeButtonIndex.
+/// Otherwise, this is the selected index of the carousel, or NSNotFound if using neither.
+@property (nonatomic) NSInteger selectedScope;
+/// self.searchController.searchBar.text
+@property (nonatomic, readonly, copy) NSString *searchText;
+
+/// A totally optional delegate to forward search results updater calls to.
+/// If a delegate is set, updateSearchResults: is not called on this view controller.
+@property (nonatomic, weak) id<FLEXSearchResultsUpdating> searchResultsUpdater;
+
+/// self.view.window as a \c FLEXWindow
+@property (nonatomic, readonly) FLEXWindow *window;
+
+/// Convenient for doing some async processor-intensive searching
+/// in the background before updating the UI back on the main queue.
+- (void)onBackgroundQueue:(NSArray *(^)(void))backgroundBlock thenOnMainQueue:(void(^)(NSArray *))mainBlock;
+
+/// Adds up to 3 additional items to the toolbar in right-to-left order.
+///
+/// That is, the first item in the given array will be the rightmost item behind
+/// any existing toolbar items. By default, buttons for bookmarks and tabs are shown.
+///
+/// If you wish to have more control over how the buttons are arranged or which
+/// buttons are displayed, you can access the properties for the pre-existing
+/// toolbar items directly and manually set \c self.toolbarItems by overriding
+/// the \c setupToolbarItems method below.
+- (void)addToolbarItems:(NSArray<UIBarButtonItem *> *)items;
+
+/// Subclasses may override. You should not need to call this method directly.
+- (void)setupToolbarItems;
+
+@property (nonatomic, readonly) UIBarButtonItem *shareToolbarItem;
+@property (nonatomic, readonly) UIBarButtonItem *bookmarksToolbarItem;
+@property (nonatomic, readonly) UIBarButtonItem *openTabsToolbarItem;
+
+/// Whether or not to display the "share" icon in the middle of the toolbar. NO by default.
+///
+/// Turning this on after you have added custom toolbar items will
+/// push off the leftmost toolbar item and shift the others leftward.
+@property (nonatomic) BOOL showsShareToolbarItem;
+/// Called when the share button is pressed.
+/// Default implementation does nothign. Subclasses may override.
+- (void)shareButtonPressed:(UIBarButtonItem *)sender;
+
+/// Subclasses may call this to opt-out of all toolbar related behavior.
+/// This is necessary if you want to disable the gesture which reveals the toolbar.
+- (void)disableToolbar;
+
+@end

Tweaks/FLEX/Core/Controllers/FLEXTableViewController.m

@@ -0,0 +1,618 @@
+//
+//  FLEXTableViewController.m
+//  FLEX
+//
+//  Created by Tanner on 7/5/19.
+//  Copyright © 2020 FLEX Team. All rights reserved.
+//
+
+#import "FLEXTableViewController.h"
+#import "FLEXExplorerViewController.h"
+#import "FLEXBookmarksViewController.h"
+#import "FLEXTabsViewController.h"
+#import "FLEXScopeCarousel.h"
+#import "FLEXTableView.h"
+#import "FLEXUtility.h"
+#import "FLEXResources.h"
+#import "UIBarButtonItem+FLEX.h"
+#import <objc/runtime.h>
+
+@interface Block : NSObject
+- (void)invoke;
+@end
+
+CGFloat const kFLEXDebounceInstant = 0.f;
+CGFloat const kFLEXDebounceFast = 0.05;
+CGFloat const kFLEXDebounceForAsyncSearch = 0.15;
+CGFloat const kFLEXDebounceForExpensiveIO = 0.5;
+
+@interface FLEXTableViewController ()
+@property (nonatomic) NSTimer *debounceTimer;
+@property (nonatomic) BOOL didInitiallyRevealSearchBar;
+@property (nonatomic) UITableViewStyle style;
+
+@property (nonatomic) BOOL hasAppeared;
+@property (nonatomic, readonly) UIView *tableHeaderViewContainer;
+
+@property (nonatomic, readonly) BOOL manuallyDeactivateSearchOnDisappear;
+
+@property (nonatomic) UIBarButtonItem *middleToolbarItem;
+@property (nonatomic) UIBarButtonItem *middleLeftToolbarItem;
+@property (nonatomic) UIBarButtonItem *leftmostToolbarItem;
+@end
+
+@implementation FLEXTableViewController
+@dynamic tableView;
+@synthesize showsShareToolbarItem = _showsShareToolbarItem;
+@synthesize tableHeaderViewContainer = _tableHeaderViewContainer;
+@synthesize automaticallyShowsSearchBarCancelButton = _automaticallyShowsSearchBarCancelButton;
+
+#pragma mark - Initialization
+
+- (id)init {
+    if (@available(iOS 13.0, *)) {
+        self = [self initWithStyle:UITableViewStyleInsetGrouped];
+    } else {
+        self = [self initWithStyle:UITableViewStyleGrouped];
+    }
+    
+    return self;
+}
+
+- (id)initWithStyle:(UITableViewStyle)style {
+    self = [super initWithStyle:style];
+    
+    if (self) {
+        _searchBarDebounceInterval = kFLEXDebounceFast;
+        _showSearchBarInitially = YES;
+        _style = style;
+        _manuallyDeactivateSearchOnDisappear = (
+            NSProcessInfo.processInfo.operatingSystemVersion.majorVersion < 11
+        );
+        
+        // We will be our own search delegate if we implement this method
+        if ([self respondsToSelector:@selector(updateSearchResults:)]) {
+            self.searchDelegate = (id)self;
+        }
+    }
+    
+    return self;
+}
+
+
+#pragma mark - Public
+
+- (FLEXWindow *)window {
+    return (id)self.view.window;
+}
+
+- (void)setShowsSearchBar:(BOOL)showsSearchBar {
+    if (_showsSearchBar == showsSearchBar) return;
+    _showsSearchBar = showsSearchBar;
+    
+    if (showsSearchBar) {
+        UIViewController *results = self.searchResultsController;
+        self.searchController = [[UISearchController alloc] initWithSearchResultsController:results];
+        self.searchController.searchBar.placeholder = @"Filter";
+        self.searchController.searchResultsUpdater = (id)self;
+        self.searchController.delegate = (id)self;
+        self.searchController.dimsBackgroundDuringPresentation = NO;
+        self.searchController.hidesNavigationBarDuringPresentation = NO;
+        /// Not necessary in iOS 13; remove this when iOS 13 is the minimum deployment target
+        self.searchController.searchBar.delegate = self;
+
+        self.automaticallyShowsSearchBarCancelButton = YES;
+
+        if (@available(iOS 13, *)) {
+            self.searchController.automaticallyShowsScopeBar = NO;
+        }
+        
+        [self addSearchController:self.searchController];
+    } else {
+        // Search already shown and just set to NO, so remove it
+        [self removeSearchController:self.searchController];
+    }
+}
+
+- (void)setShowsCarousel:(BOOL)showsCarousel {
+    if (_showsCarousel == showsCarousel) return;
+    _showsCarousel = showsCarousel;
+    
+    if (showsCarousel) {
+        _carousel = ({ weakify(self)
+            
+            FLEXScopeCarousel *carousel = [FLEXScopeCarousel new];
+            carousel.selectedIndexChangedAction = ^(NSInteger idx) { strongify(self);
+                [self.searchDelegate updateSearchResults:self.searchText];
+            };
+
+            // UITableView won't update the header size unless you reset the header view
+            [carousel registerBlockForDynamicTypeChanges:^(FLEXScopeCarousel *_) { strongify(self);
+                [self layoutTableHeaderIfNeeded];
+            }];
+
+            carousel;
+        });
+        [self addCarousel:_carousel];
+    } else {
+        // Carousel already shown and just set to NO, so remove it
+        [self removeCarousel:_carousel];
+    }
+}
+
+- (NSInteger)selectedScope {
+    if (self.searchController.searchBar.showsScopeBar) {
+        return self.searchController.searchBar.selectedScopeButtonIndex;
+    } else if (self.showsCarousel) {
+        return self.carousel.selectedIndex;
+    } else {
+        return 0;
+    }
+}
+
+- (void)setSelectedScope:(NSInteger)selectedScope {
+    if (self.searchController.searchBar.showsScopeBar) {
+        self.searchController.searchBar.selectedScopeButtonIndex = selectedScope;
+    } else if (self.showsCarousel) {
+        self.carousel.selectedIndex = selectedScope;
+    }
+
+    [self.searchDelegate updateSearchResults:self.searchText];
+}
+
+- (NSString *)searchText {
+    return self.searchController.searchBar.text;
+}
+
+- (BOOL)automaticallyShowsSearchBarCancelButton {
+    if (@available(iOS 13, *)) {
+        return self.searchController.automaticallyShowsCancelButton;
+    }
+
+    return _automaticallyShowsSearchBarCancelButton;
+}
+
+- (void)setAutomaticallyShowsSearchBarCancelButton:(BOOL)value {
+    if (@available(iOS 13, *)) {
+        self.searchController.automaticallyShowsCancelButton = value;
+    }
+
+    _automaticallyShowsSearchBarCancelButton = value;
+}
+
+- (void)onBackgroundQueue:(NSArray *(^)(void))backgroundBlock thenOnMainQueue:(void(^)(NSArray *))mainBlock {
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+        NSArray *items = backgroundBlock();
+        dispatch_async(dispatch_get_main_queue(), ^{
+            mainBlock(items);
+        });
+    });
+}
+
+- (void)setsShowsShareToolbarItem:(BOOL)showsShareToolbarItem {
+    _showsShareToolbarItem = showsShareToolbarItem;
+    if (self.isViewLoaded) {
+        [self setupToolbarItems];
+    }
+}
+
+- (void)disableToolbar {
+    self.navigationController.toolbarHidden = YES;
+    self.navigationController.hidesBarsOnSwipe = NO;
+    self.toolbarItems = nil;
+}
+
+
+#pragma mark - View Controller Lifecycle
+
+- (void)loadView {
+    self.view = [FLEXTableView style:self.style];
+    self.tableView.dataSource = self;
+    self.tableView.delegate = self;
+    
+    _shareToolbarItem = FLEXBarButtonItemSystem(Action, self, @selector(shareButtonPressed:));
+    _bookmarksToolbarItem = [UIBarButtonItem
+        flex_itemWithImage:FLEXResources.bookmarksIcon target:self action:@selector(showBookmarks)
+    ];
+    _openTabsToolbarItem = [UIBarButtonItem
+        flex_itemWithImage:FLEXResources.openTabsIcon target:self action:@selector(showTabSwitcher)
+    ];
+    
+    self.leftmostToolbarItem = UIBarButtonItem.flex_fixedSpace;
+    self.middleLeftToolbarItem = UIBarButtonItem.flex_fixedSpace;
+    self.middleToolbarItem = UIBarButtonItem.flex_fixedSpace;
+}
+
+- (void)viewDidLoad {
+    [super viewDidLoad];
+    
+    self.tableView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
+    
+    // Toolbar
+    self.navigationController.toolbarHidden = self.toolbarItems.count > 0;
+    self.navigationController.hidesBarsOnSwipe = YES;
+
+    // On iOS 13, the root view controller shows it's search bar no matter what.
+    // Turning this off avoids some weird flash the navigation bar does when we
+    // toggle navigationItem.hidesSearchBarWhenScrolling on and off. The flash
+    // will still happen on subsequent view controllers, but we can at least
+    // avoid it for the root view controller
+    if (@available(iOS 13, *)) {
+        if (self.navigationController.viewControllers.firstObject == self) {
+            _showSearchBarInitially = NO;
+        }
+    }
+}
+
+- (void)viewWillAppear:(BOOL)animated {
+    [super viewWillAppear:animated];
+    
+    if (@available(iOS 11.0, *)) {
+        // When going back, make the search bar reappear instead of hiding
+        if ((self.pinSearchBar || self.showSearchBarInitially) && !self.didInitiallyRevealSearchBar) {
+            self.navigationItem.hidesSearchBarWhenScrolling = NO;
+        }
+    }
+    
+    // Make the keyboard seem to appear faster
+    if (self.activatesSearchBarAutomatically) {
+        [self makeKeyboardAppearNow];
+    }
+
+    [self setupToolbarItems];
+}
+
+- (void)viewDidAppear:(BOOL)animated {
+    [super viewDidAppear:animated];
+
+    // Allow scrolling to collapse the search bar, only if we don't want it pinned
+    if (@available(iOS 11.0, *)) {
+        if (self.showSearchBarInitially && !self.pinSearchBar && !self.didInitiallyRevealSearchBar) {
+            // All this mumbo jumbo is necessary to work around a bug in iOS 13 up to 13.2
+            // wherein quickly toggling navigationItem.hidesSearchBarWhenScrolling to make
+            // the search bar appear initially results in a bugged search bar that
+            // becomes transparent and floats over the screen as you scroll
+            [UIView animateWithDuration:0.2 animations:^{
+                self.navigationItem.hidesSearchBarWhenScrolling = YES;
+                [self.navigationController.view setNeedsLayout];
+                [self.navigationController.view layoutIfNeeded];
+            }];
+        }
+    }
+    
+    if (self.activatesSearchBarAutomatically) {
+        // Keyboard has appeared, now we call this as we soon present our search bar
+        [self removeDummyTextField];
+        
+        // Activate the search bar
+        dispatch_async(dispatch_get_main_queue(), ^{
+            // This doesn't work unless it's wrapped in this dispatch_async call
+            [self.searchController.searchBar becomeFirstResponder];
+        });
+    }
+
+    // We only want to reveal the search bar when the view controller first appears.
+    self.didInitiallyRevealSearchBar = YES;
+}
+
+- (void)viewWillDisappear:(BOOL)animated {
+    [super viewWillDisappear:animated];
+    
+    if (self.manuallyDeactivateSearchOnDisappear && self.searchController.isActive) {
+        self.searchController.active = NO;
+    }
+}
+
+- (void)didMoveToParentViewController:(UIViewController *)parent {
+    [super didMoveToParentViewController:parent];
+    // Reset this since we are re-appearing under a new
+    // parent view controller and need to show it again
+    self.didInitiallyRevealSearchBar = NO;
+}
+
+
+#pragma mark - Toolbar, Public
+
+- (void)setupToolbarItems {
+    if (!self.isViewLoaded) {
+        return;
+    }
+    
+    self.toolbarItems = @[
+        self.leftmostToolbarItem,
+        UIBarButtonItem.flex_flexibleSpace,
+        self.middleLeftToolbarItem,
+        UIBarButtonItem.flex_flexibleSpace,
+        self.middleToolbarItem,
+        UIBarButtonItem.flex_flexibleSpace,
+        self.bookmarksToolbarItem,
+        UIBarButtonItem.flex_flexibleSpace,
+        self.openTabsToolbarItem,
+    ];
+    
+    for (UIBarButtonItem *item in self.toolbarItems) {
+        [item _setWidth:60];
+        // This does not work for anything but fixed spaces for some reason
+        // item.width = 60;
+    }
+    
+    // Disable tabs entirely when not presented by FLEXExplorerViewController
+    UIViewController *presenter = self.navigationController.presentingViewController;
+    if (![presenter isKindOfClass:[FLEXExplorerViewController class]]) {
+        self.openTabsToolbarItem.enabled = NO;
+    }
+}
+
+- (void)addToolbarItems:(NSArray<UIBarButtonItem *> *)items {
+    if (self.showsShareToolbarItem) {
+        // Share button is in the middle, skip middle button
+        if (items.count > 0) {
+            self.middleLeftToolbarItem = items[0];
+        }
+        if (items.count > 1) {
+            self.leftmostToolbarItem = items[1];
+        }
+    } else {
+        // Add buttons right-to-left
+        if (items.count > 0) {
+            self.middleToolbarItem = items[0];
+        }
+        if (items.count > 1) {
+            self.middleLeftToolbarItem = items[1];
+        }
+        if (items.count > 2) {
+            self.leftmostToolbarItem = items[2];
+        }
+    }
+    
+    [self setupToolbarItems];
+}
+
+- (void)setShowsShareToolbarItem:(BOOL)showShare {
+    if (_showsShareToolbarItem != showShare) {
+        _showsShareToolbarItem = showShare;
+        
+        if (showShare) {
+            // Push out leftmost item
+            self.leftmostToolbarItem = self.middleLeftToolbarItem;
+            self.middleLeftToolbarItem = self.middleToolbarItem;
+            
+            // Use share for middle
+            self.middleToolbarItem = self.shareToolbarItem;
+        } else {
+            // Remove share, shift custom items rightward
+            self.middleToolbarItem = self.middleLeftToolbarItem;
+            self.middleLeftToolbarItem = self.leftmostToolbarItem;
+            self.leftmostToolbarItem = UIBarButtonItem.flex_fixedSpace;
+        }
+    }
+    
+    [self setupToolbarItems];
+}
+
+- (void)shareButtonPressed:(UIBarButtonItem *)sender {
+
+}
+
+
+#pragma mark - Private
+
+- (void)debounce:(void(^)(void))block {
+    [self.debounceTimer invalidate];
+    
+    self.debounceTimer = [NSTimer
+        scheduledTimerWithTimeInterval:self.searchBarDebounceInterval
+        target:block
+        selector:@selector(invoke)
+        userInfo:nil
+        repeats:NO
+    ];
+}
+
+- (void)layoutTableHeaderIfNeeded {
+    if (self.showsCarousel) {
+        self.carousel.frame = FLEXRectSetHeight(
+            self.carousel.frame, self.carousel.intrinsicContentSize.height
+        );
+    }
+    
+    self.tableView.tableHeaderView = self.tableView.tableHeaderView;
+}
+
+- (void)addCarousel:(FLEXScopeCarousel *)carousel {
+    if (@available(iOS 11.0, *)) {
+        self.tableView.tableHeaderView = carousel;
+    } else {
+        carousel.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleTopMargin;
+        
+        CGRect frame = self.tableHeaderViewContainer.frame;
+        CGRect subviewFrame = carousel.frame;
+        subviewFrame.origin.y = 0;
+        
+        // Put the carousel below the search bar if it's already there
+        if (self.showsSearchBar) {
+            carousel.frame = subviewFrame = FLEXRectSetY(
+                subviewFrame, self.searchController.searchBar.frame.size.height
+            );
+            frame.size.height += carousel.intrinsicContentSize.height;
+        } else {
+            frame.size.height = carousel.intrinsicContentSize.height;
+        }
+        
+        self.tableHeaderViewContainer.frame = frame;
+        [self.tableHeaderViewContainer addSubview:carousel];
+    }
+    
+    [self layoutTableHeaderIfNeeded];
+}
+
+- (void)removeCarousel:(FLEXScopeCarousel *)carousel {
+    [carousel removeFromSuperview];
+    
+    if (@available(iOS 11.0, *)) {
+        self.tableView.tableHeaderView = nil;
+    } else {
+        if (self.showsSearchBar) {
+            [self removeSearchController:self.searchController];
+            [self addSearchController:self.searchController];
+        } else {
+            self.tableView.tableHeaderView = nil;
+            _tableHeaderViewContainer = nil;
+        }
+    }
+}
+
+- (void)addSearchController:(UISearchController *)controller {
+    if (@available(iOS 11.0, *)) {
+        self.navigationItem.searchController = controller;
+    } else {
+        controller.searchBar.autoresizingMask |= UIViewAutoresizingFlexibleBottomMargin;
+        [self.tableHeaderViewContainer addSubview:controller.searchBar];
+        CGRect subviewFrame = controller.searchBar.frame;
+        CGRect frame = self.tableHeaderViewContainer.frame;
+        frame.size.width = MAX(frame.size.width, subviewFrame.size.width);
+        frame.size.height = subviewFrame.size.height;
+        
+        // Move the carousel down if it's already there
+        if (self.showsCarousel) {
+            self.carousel.frame = FLEXRectSetY(
+                self.carousel.frame, subviewFrame.size.height
+            );
+            frame.size.height += self.carousel.frame.size.height;
+        }
+        
+        self.tableHeaderViewContainer.frame = frame;
+        [self layoutTableHeaderIfNeeded];
+    }
+}
+
+- (void)removeSearchController:(UISearchController *)controller {
+    if (@available(iOS 11.0, *)) {
+        self.navigationItem.searchController = nil;
+    } else {
+        [controller.searchBar removeFromSuperview];
+        
+        if (self.showsCarousel) {
+//            self.carousel.frame = FLEXRectRemake(CGPointZero, self.carousel.frame.size);
+            [self removeCarousel:self.carousel];
+            [self addCarousel:self.carousel];
+        } else {
+            self.tableView.tableHeaderView = nil;
+            _tableHeaderViewContainer = nil;
+        }
+    }
+}
+
+- (UIView *)tableHeaderViewContainer {
+    if (!_tableHeaderViewContainer) {
+        _tableHeaderViewContainer = [UIView new];
+        self.tableView.tableHeaderView = self.tableHeaderViewContainer;
+    }
+    
+    return _tableHeaderViewContainer;
+}
+
+- (void)showBookmarks {
+    UINavigationController *nav = [[UINavigationController alloc]
+        initWithRootViewController:[FLEXBookmarksViewController new]
+    ];
+    [self presentViewController:nav animated:YES completion:nil];
+}
+
+- (void)showTabSwitcher {
+    UINavigationController *nav = [[UINavigationController alloc]
+        initWithRootViewController:[FLEXTabsViewController new]
+    ];
+    [self presentViewController:nav animated:YES completion:nil];
+}
+
+
+#pragma mark - Search Bar
+
+#pragma mark Faster keyboard
+
+static UITextField *kDummyTextField = nil;
+
+/// Make the keyboard appear instantly. We use this to make the
+/// keyboard appear faster when the search bar is set to appear initially.
+/// You must call \c -removeDummyTextField before your search bar is to appear.
+- (void)makeKeyboardAppearNow {
+    if (!kDummyTextField) {
+        kDummyTextField = [UITextField new];
+        kDummyTextField.autocorrectionType = UITextAutocorrectionTypeNo;
+    }
+    
+    kDummyTextField.inputAccessoryView = self.searchController.searchBar.inputAccessoryView;
+    [UIApplication.sharedApplication.keyWindow addSubview:kDummyTextField];
+    [kDummyTextField becomeFirstResponder];
+}
+
+- (void)removeDummyTextField {
+    if (kDummyTextField.superview) {
+        [kDummyTextField removeFromSuperview];
+    }
+}
+
+#pragma mark UISearchResultsUpdating
+
+- (void)updateSearchResultsForSearchController:(UISearchController *)searchController {
+    [self.debounceTimer invalidate];
+    NSString *text = searchController.searchBar.text;
+    
+    void (^updateSearchResults)(void) = ^{
+        if (self.searchResultsUpdater) {
+            [self.searchResultsUpdater updateSearchResults:text];
+        } else {
+            [self.searchDelegate updateSearchResults:text];
+        }
+    };
+    
+    // Only debounce if we want to, and if we have a non-empty string
+    // Empty string events are sent instantly
+    if (text.length && self.searchBarDebounceInterval > kFLEXDebounceInstant) {
+        [self debounce:updateSearchResults];
+    } else {
+        updateSearchResults();
+    }
+}
+
+
+#pragma mark UISearchControllerDelegate
+
+- (void)willPresentSearchController:(UISearchController *)searchController {
+    // Manually show cancel button for < iOS 13
+    if (!@available(iOS 13, *) && self.automaticallyShowsSearchBarCancelButton) {
+        [searchController.searchBar setShowsCancelButton:YES animated:YES];
+    }
+}
+
+- (void)willDismissSearchController:(UISearchController *)searchController {
+    // Manually hide cancel button for < iOS 13
+    if (!@available(iOS 13, *) && self.automaticallyShowsSearchBarCancelButton) {
+        [searchController.searchBar setShowsCancelButton:NO animated:YES];
+    }
+}
+
+
+#pragma mark UISearchBarDelegate
+
+/// Not necessary in iOS 13; remove this when iOS 13 is the deployment target
+- (void)searchBar:(UISearchBar *)searchBar selectedScopeButtonIndexDidChange:(NSInteger)selectedScope {
+    [self updateSearchResultsForSearchController:self.searchController];
+}
+
+
+#pragma mark Table View
+
+/// Not having a title in the first section looks weird with a rounded-corner table view style
+- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
+    if (@available(iOS 13, *)) {
+        if (self.style == UITableViewStyleInsetGrouped) {
+            return @" ";
+        }
+    }
+
+    return nil; // For plain/gropued style
+}
+
+@end