Merge branch 'charlesmchen/bottomViewAnimations'

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -214,6 +214,7 @@ typedef enum : NSUInteger {
 @property (nonatomic) BOOL isViewCompletelyAppeared;
 @property (nonatomic) BOOL isViewVisible;
 @property (nonatomic) BOOL shouldObserveVMUpdates;
+@property (nonatomic) BOOL shouldAnimateKeyboardChanges;
 @property (nonatomic) BOOL viewHasEverAppeared;
 @property (nonatomic) BOOL hasUnreadMessages;
 @property (nonatomic) BOOL isPickingMediaAsDocument;
@@ -1230,6 +1231,7 @@ typedef enum : NSUInteger {
 
     self.isViewCompletelyAppeared = YES;
     self.viewHasEverAppeared = YES;
+    self.shouldAnimateKeyboardChanges = YES;
 
     // HACK: Because the inputToolbar is the inputAccessoryView, we make some special considertations WRT it's firstResponder status.
     //
@@ -1291,6 +1293,7 @@ typedef enum : NSUInteger {
     [super viewDidDisappear:animated];
     self.userHasScrolled = NO;
     self.isViewVisible = NO;
+    self.shouldAnimateKeyboardChanges = NO;
 
     [self.audioAttachmentPlayer stop];
     self.audioAttachmentPlayer = nil;
@@ -3720,12 +3723,21 @@ typedef enum : NSUInteger {
         return;
     }
     CGRect keyboardEndFrame = [keyboardEndFrameValue CGRectValue];
+    CGRect keyboardEndFrameConverted = [self.view convertRect:keyboardEndFrame fromView:nil];
 
     UIEdgeInsets oldInsets = self.collectionView.contentInset;
     UIEdgeInsets newInsets = oldInsets;
 
-    // bottomLayoutGuide accounts for extra offset needed on iPhoneX
-    newInsets.bottom = keyboardEndFrame.size.height - self.bottomLayoutGuide.length;
+    // Use a content inset that so that the conversation content
+    // is not hidden behind the keyboard + input accessory.
+    //
+    // Make sure to leave space for the bottom layout guide (the notch).
+    //
+    // Always reserve room for the input accessory, which we display even
+    // if the keyboard is not active.
+    newInsets.bottom = MAX(0,
+        MAX(self.view.height - self.bottomLayoutGuide.length - keyboardEndFrameConverted.origin.y,
+            self.inputToolbar.height));
 
     BOOL wasScrolledToBottom = [self isScrolledToBottom];
 
@@ -3774,7 +3786,7 @@ typedef enum : NSUInteger {
         }
     };
 
-    if (self.isViewCompletelyAppeared) {
+    if (self.shouldAnimateKeyboardChanges && CurrentAppContext().isAppForegroundAndActive) {
         adjustInsets();
     } else {
         // Even though we are scrolling without explicitly animating, the notification seems to occur within the context

Signal/src/ViewControllers/Registration/OnboardingBaseViewController.swift

@@ -73,6 +73,12 @@ public class OnboardingBaseViewController: OWSViewController {
 
     // MARK: - View Lifecycle
 
+    public override func viewDidLoad() {
+        super.viewDidLoad()
+
+        self.shouldBottomViewReserveSpaceForKeyboard = true
+    }
+
     public override func viewWillAppear(_ animated: Bool) {
         super.viewWillAppear(animated)
 

SignalMessaging/ViewControllers/OWSViewController.h

@@ -20,6 +20,10 @@ UIInterfaceOrientationMask DefaultUIInterfaceOrientationMask(void);
 // BUT adjust its location upward if the keyboard appears.
 - (void)autoPinViewToBottomOfViewControllerOrKeyboard:(UIView *)view avoidNotch:(BOOL)avoidNotch;
 
+// If YES, the bottom view never "reclaims" layout space if the keyboard is dismissed.
+// Defaults to NO.
+@property (nonatomic) BOOL shouldBottomViewReserveSpaceForKeyboard;
+
 @end
 
 NS_ASSUME_NONNULL_END

SignalMessaging/ViewControllers/OWSViewController.m

@@ -23,6 +23,7 @@ UIInterfaceOrientationMask DefaultUIInterfaceOrientationMask(void)
 
 @property (nonatomic, weak) UIView *bottomLayoutView;
 @property (nonatomic) NSLayoutConstraint *bottomLayoutConstraint;
+@property (nonatomic) BOOL shouldAnimateBottomLayout;
 
 @end
 
@@ -64,6 +65,22 @@ UIInterfaceOrientationMask DefaultUIInterfaceOrientationMask(void)
     return self;
 }
 
+#pragma mark - View Lifecycle
+
+- (void)viewDidAppear:(BOOL)animated
+{
+    [super viewDidAppear:animated];
+
+    self.shouldAnimateBottomLayout = YES;
+}
+
+- (void)viewDidDisappear:(BOOL)animated
+{
+    [super viewDidDisappear:animated];
+
+    self.shouldAnimateBottomLayout = NO;
+}
+
 - (void)viewDidLoad
 {
     [super viewDidLoad];
@@ -73,6 +90,8 @@ UIInterfaceOrientationMask DefaultUIInterfaceOrientationMask(void)
     }
 }
 
+#pragma mark -
+
 - (void)autoPinViewToBottomOfViewControllerOrKeyboard:(UIView *)view avoidNotch:(BOOL)avoidNotch
 {
     OWSAssertDebug(view);
@@ -185,11 +204,27 @@ UIInterfaceOrientationMask DefaultUIInterfaceOrientationMask(void)
     // bar.
     CGFloat offset = -MAX(0, (self.view.height - self.bottomLayoutGuide.length - keyboardEndFrameConverted.origin.y));
 
-    // There's no need to use: [UIView animateWithDuration:...].
-    // Any layout changes made during these notifications are
-    // automatically animated.
-    self.bottomLayoutConstraint.constant = offset;
-    [self.bottomLayoutView.superview layoutIfNeeded];
+    dispatch_block_t updateLayout = ^{
+        if (self.shouldBottomViewReserveSpaceForKeyboard && offset >= 0) {
+            // To avoid unnecessary animations / layout jitter,
+            // some views never reclaim layout space when the keyboard is dismissed.
+            //
+            // They _do_ need to relayout if the user switches keyboards.
+            return;
+        }
+        self.bottomLayoutConstraint.constant = offset;
+        [self.bottomLayoutView.superview layoutIfNeeded];
+    };
+
+
+    if (self.shouldAnimateBottomLayout && CurrentAppContext().isAppForegroundAndActive) {
+        updateLayout();
+    } else {
+        // UIKit by default animates all changes in response to keyboard events.
+        // We want to suppress those animations if the view isn't visible,
+        // otherwise presentation animations don't work properly.
+        [UIView performWithoutAnimation:updateLayout];
+    }
 }
 
 #pragma mark - Orientation