Merge MatrixKit develop with commit hash: b85b736313bec0592bd1cabc68035d97f5331137

Riot/Modules/MatrixKit/Views/RoomTitle/MXKRoomTitleView.h

@@ -0,0 +1,120 @@
+/*
+ Copyright 2015 OpenMarket Ltd
+ Copyright 2017 Vector Creations Ltd
+ 
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ 
+ http://www.apache.org/licenses/LICENSE-2.0
+ 
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import <MatrixSDK/MatrixSDK.h>
+
+#import "MXKView.h"
+
+@class MXKRoomTitleView;
+@protocol MXKRoomTitleViewDelegate <NSObject>
+
+/**
+ Tells the delegate that an alert must be presented.
+ 
+ @param titleView the room title view.
+ @param alertController the alert to present.
+ */
+- (void)roomTitleView:(MXKRoomTitleView*)titleView presentAlertController:(UIAlertController*)alertController;
+
+/**
+ Asks the delegate if editing should begin
+
+ @param titleView the room title view.
+ @return  YES if an editing session should be initiated; otherwise, NO to disallow editing.
+ */
+- (BOOL)roomTitleViewShouldBeginEditing:(MXKRoomTitleView*)titleView;
+
+@optional
+
+/**
+ Tells the delegate that the saving of user's changes is in progress or is finished.
+ 
+ @param titleView the room title view.
+ @param saving YES if a request is running to save user's changes.
+ */
+- (void)roomTitleView:(MXKRoomTitleView*)titleView isSaving:(BOOL)saving;
+
+@end
+
+/**
+ 'MXKRoomTitleView' instance displays editable room display name.
+ */
+@interface MXKRoomTitleView : MXKView <UITextFieldDelegate>
+{
+@protected
+    /**
+     Potential alert.
+     */
+    UIAlertController *currentAlert;
+    
+    /**
+     Test fields input accessory.
+     */
+    UIView *inputAccessoryView;
+}
+
+@property (weak, nonatomic) IBOutlet UITextField *displayNameTextField;
+@property (weak, nonatomic) IBOutlet NSLayoutConstraint *displayNameTextFieldTopConstraint;
+
+@property (strong, nonatomic) MXRoom *mxRoom;
+@property (nonatomic) BOOL editable;
+@property (nonatomic) BOOL isEditing;
+
+/**
+ *  Returns the `UINib` object initialized for the room title view.
+ *
+ *  @return The initialized `UINib` object or `nil` if there were errors during
+ *  initialization or the nib file could not be located.
+ */
++ (UINib *)nib;
+
+/**
+ Creates and returns a new `MXKRoomTitleView-inherited` object.
+ 
+ @discussion This is the designated initializer for programmatic instantiation.
+ @return An initialized `MXKRoomTitleView-inherited` object if successful, `nil` otherwise.
+ */
++ (instancetype)roomTitleView;
+
+/**
+ The delegate notified when inputs are ready.
+ */
+@property (weak, nonatomic) id<MXKRoomTitleViewDelegate> delegate;
+
+/**
+ The custom accessory view associated to all text field of this 'MXKRoomTitleView' instance.
+ This view is actually used to retrieve the keyboard view. Indeed the keyboard view is the superview of
+ this accessory view when a text field become the first responder.
+ */
+@property (readonly) UIView *inputAccessoryView;
+
+/**
+ Dismiss keyboard.
+ */
+- (void)dismissKeyboard;
+
+/**
+ Force title view refresh.
+ */
+- (void)refreshDisplay;
+
+/**
+ Dispose view resources and listener.
+ */
+- (void)destroy;
+
+@end

Riot/Modules/MatrixKit/Views/RoomTitle/MXKRoomTitleView.m

@@ -0,0 +1,279 @@
+/*
+ Copyright 2015 OpenMarket Ltd
+ Copyright 2017 Vector Creations Ltd
+ Copyright 2018 New Vector Ltd
+ 
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ 
+ http://www.apache.org/licenses/LICENSE-2.0
+ 
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import "MXKRoomTitleView.h"
+
+#import "MXKConstants.h"
+
+#import "NSBundle+MatrixKit.h"
+#import "MXRoom+Sync.h"
+
+#import "MXKSwiftHeader.h"
+
+@interface MXKRoomTitleView ()
+{
+    // Observer kMXRoomSummaryDidChangeNotification to keep updated the room name.
+    __weak id mxRoomSummaryDidChangeObserver;
+}
+@end
+
+@implementation MXKRoomTitleView
+@synthesize inputAccessoryView;
+
++ (UINib *)nib
+{
+    return [UINib nibWithNibName:NSStringFromClass([MXKRoomTitleView class])
+                          bundle:[NSBundle bundleForClass:[MXKRoomTitleView class]]];
+}
+
+- (void)awakeFromNib
+{
+    [super awakeFromNib];
+    
+    [self setTranslatesAutoresizingMaskIntoConstraints: NO];
+    
+    // Add an accessory view to the text view in order to retrieve keyboard view.
+    inputAccessoryView = [[UIView alloc] initWithFrame:CGRectZero];
+    self.displayNameTextField.inputAccessoryView = inputAccessoryView;
+    
+    self.displayNameTextField.enabled = NO;
+    self.displayNameTextField.returnKeyType = UIReturnKeyDone;
+    self.displayNameTextField.hidden = YES;
+}
+
++ (instancetype)roomTitleView
+{
+    return [[[self class] nib] instantiateWithOwner:nil options:nil].firstObject;
+}
+
+- (void)dealloc
+{
+    inputAccessoryView = nil;
+}
+
+#pragma mark - Override MXKView
+
+-(void)customizeViewRendering
+{
+    [super customizeViewRendering];
+    
+    self.autoresizingMask = UIViewAutoresizingFlexibleWidth;
+}
+
+#pragma mark -
+
+- (void)refreshDisplay
+{
+    if (_mxRoom)
+    {
+        // Replace empty string by nil : avoid having the placeholder 'Room name" when there is no displayname
+        self.displayNameTextField.text = (_mxRoom.summary.displayname.length) ? _mxRoom.summary.displayname : nil;
+    }
+    else
+    {
+        self.displayNameTextField.text = [MatrixKitL10n roomPleaseSelect];
+        self.displayNameTextField.enabled = NO;
+    }
+    self.displayNameTextField.hidden = NO;
+}
+
+- (void)destroy
+{
+    self.delegate = nil;
+    self.mxRoom = nil;
+    
+    if (mxRoomSummaryDidChangeObserver)
+    {
+        [NSNotificationCenter.defaultCenter removeObserver:mxRoomSummaryDidChangeObserver];
+        mxRoomSummaryDidChangeObserver = nil;
+    }
+}
+
+- (void)dismissKeyboard
+{
+    // Hide the keyboard
+    [self.displayNameTextField resignFirstResponder];
+}
+
+#pragma mark -
+
+- (void)setMxRoom:(MXRoom *)mxRoom
+{
+    // Check whether the room is actually changed
+    if (_mxRoom != mxRoom)
+    {
+        // Remove potential listener
+        if (mxRoomSummaryDidChangeObserver)
+        {
+            [[NSNotificationCenter defaultCenter] removeObserver:mxRoomSummaryDidChangeObserver];
+            mxRoomSummaryDidChangeObserver = nil;
+        }
+        
+        if (mxRoom)
+        {
+            MXWeakify(self);
+            
+            // Register a listener to handle the room name change
+            mxRoomSummaryDidChangeObserver = [[NSNotificationCenter defaultCenter] addObserverForName:kMXRoomSummaryDidChangeNotification object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *notif) {
+                
+                MXStrongifyAndReturnIfNil(self);
+                
+                // Check whether the text field is editing before refreshing title view
+                if (!self.isEditing)
+                {
+                    [self refreshDisplay];
+                }
+                
+            }];
+        }
+        _mxRoom = mxRoom;
+    }
+    // Force refresh
+    [self refreshDisplay];
+}
+
+- (void)setEditable:(BOOL)editable
+{
+    self.displayNameTextField.enabled = editable;
+}
+
+- (BOOL)isEditing
+{
+    return self.displayNameTextField.isEditing;
+}
+
+#pragma mark - UITextField delegate
+
+- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
+{
+    // check if the deleaget allows the edition
+    if (!self.delegate || [self.delegate roomTitleViewShouldBeginEditing:self])
+    {
+        NSString *alertMsg = nil;
+        
+        if (textField == self.displayNameTextField)
+        {
+            // Check whether the user has enough power to rename the room
+            MXRoomPowerLevels *powerLevels = _mxRoom.dangerousSyncState.powerLevels;
+
+            NSInteger userPowerLevel = [powerLevels powerLevelOfUserWithUserID:_mxRoom.mxSession.myUser.userId];
+            if (userPowerLevel >= [powerLevels minimumPowerLevelForSendingEventAsStateEvent:kMXEventTypeStringRoomName])
+            {
+                // Only the room name is edited here, update the text field with the room name
+                textField.text = _mxRoom.summary.displayname;
+                textField.backgroundColor = [UIColor whiteColor];
+            }
+            else
+            {
+                alertMsg = [MatrixKitL10n roomErrorNameEditionNotAuthorized];
+            }
+        }
+        
+        if (alertMsg)
+        {
+            // Alert user
+            __weak typeof(self) weakSelf = self;
+            if (currentAlert)
+            {
+                [currentAlert dismissViewControllerAnimated:NO completion:nil];
+            }
+            
+            currentAlert = [UIAlertController alertControllerWithTitle:nil message:alertMsg preferredStyle:UIAlertControllerStyleAlert];
+            
+            [currentAlert addAction:[UIAlertAction actionWithTitle:[MatrixKitL10n cancel]
+                                                      style:UIAlertActionStyleDefault
+                                                    handler:^(UIAlertAction * action) {
+                                                        
+                                                        typeof(self) self = weakSelf;
+                                                        self->currentAlert = nil;
+                                                        
+                                                    }]];
+            
+            [self.delegate roomTitleView:self presentAlertController:currentAlert];
+            return NO;
+        }
+        return YES;
+    }
+    else
+    {
+        return NO;
+    }
+}
+
+- (void)textFieldDidEndEditing:(UITextField *)textField
+{
+    if (textField == self.displayNameTextField)
+    {
+        textField.backgroundColor = [UIColor clearColor];
+        
+        NSString *roomName = textField.text;
+        if ((roomName.length || _mxRoom.summary.displayname.length) && [roomName isEqualToString:_mxRoom.summary.displayname] == NO)
+        {
+            if ([self.delegate respondsToSelector:@selector(roomTitleView:isSaving:)])
+            {
+                [self.delegate roomTitleView:self isSaving:YES];
+            }
+            
+            __weak typeof(self) weakSelf = self;
+            [_mxRoom setName:roomName success:^{
+                
+                if (weakSelf)
+                {
+                    typeof(weakSelf)strongSelf = weakSelf;
+                    if ([strongSelf.delegate respondsToSelector:@selector(roomTitleView:isSaving:)])
+                    {
+                        [strongSelf.delegate roomTitleView:strongSelf isSaving:NO];
+                    }
+                }
+                
+            } failure:^(NSError *error) {
+                
+                if (weakSelf)
+                {
+                    typeof(weakSelf)strongSelf = weakSelf;
+                    if ([strongSelf.delegate respondsToSelector:@selector(roomTitleView:isSaving:)])
+                    {
+                        [strongSelf.delegate roomTitleView:strongSelf isSaving:NO];
+                    }
+                    
+                    // Revert change
+                    textField.text = strongSelf.mxRoom.summary.displayname;
+                    MXLogDebug(@"[MXKRoomTitleView] Rename room failed");
+                    // Notify MatrixKit user
+                    NSString *myUserId = strongSelf.mxRoom.mxSession.myUser.userId;
+                    [[NSNotificationCenter defaultCenter] postNotificationName:kMXKErrorNotification object:error userInfo:myUserId ? @{kMXKErrorUserIdKey: myUserId} : nil];
+                }
+                
+            }];
+        }
+        else
+        {
+            // No change on room name, restore title with room displayName
+            textField.text = _mxRoom.summary.displayname;
+        }
+    }
+}
+
+- (BOOL)textFieldShouldReturn:(UITextField*) textField
+{
+    // "Done" key has been pressed
+    [textField resignFirstResponder];
+    return YES;
+}
+
+@end

Riot/Modules/MatrixKit/Views/RoomTitle/MXKRoomTitleView.xib

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="11762" systemVersion="16C67" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES">
+    <device id="retina4_7" orientation="portrait">
+        <adaptation id="fullscreen"/>
+    </device>
+    <dependencies>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="11757"/>
+        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
+    </dependencies>
+    <objects>
+        <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner"/>
+        <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
+        <view contentMode="scaleToFill" id="Wek-LA-v7p" customClass="MXKRoomTitleView">
+            <rect key="frame" x="0.0" y="0.0" width="600" height="44"/>
+            <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+            <subviews>
+                <textField opaque="NO" clipsSubviews="YES" contentMode="scaleToFill" contentHorizontalAlignment="left" contentVerticalAlignment="center" placeholder="Room Name" textAlignment="center" minimumFontSize="14" translatesAutoresizingMaskIntoConstraints="NO" id="hag-WW-XxJ">
+                    <rect key="frame" x="0.0" y="5" width="600" height="21"/>
+                    <color key="backgroundColor" red="0.0" green="0.0" blue="0.0" alpha="0.0" colorSpace="custom" customColorSpace="sRGB"/>
+                    <fontDescription key="fontDescription" type="system" pointSize="17"/>
+                    <textInputTraits key="textInputTraits" returnKeyType="next"/>
+                    <connections>
+                        <outlet property="delegate" destination="Wek-LA-v7p" id="J7I-R9-BkF"/>
+                    </connections>
+                </textField>
+            </subviews>
+            <color key="backgroundColor" red="0.0" green="0.0" blue="0.0" alpha="0.0" colorSpace="custom" customColorSpace="sRGB"/>
+            <constraints>
+                <constraint firstAttribute="trailing" secondItem="hag-WW-XxJ" secondAttribute="trailing" id="LaZ-Yg-BjR"/>
+                <constraint firstItem="hag-WW-XxJ" firstAttribute="leading" secondItem="Wek-LA-v7p" secondAttribute="leading" id="MyD-YH-Cln"/>
+                <constraint firstItem="hag-WW-XxJ" firstAttribute="top" secondItem="Wek-LA-v7p" secondAttribute="top" constant="5" id="c4c-HK-oti"/>
+            </constraints>
+            <freeformSimulatedSizeMetrics key="simulatedDestinationMetrics"/>
+            <connections>
+                <outlet property="displayNameTextField" destination="hag-WW-XxJ" id="1AJ-rc-7Rg"/>
+                <outlet property="displayNameTextFieldTopConstraint" destination="c4c-HK-oti" id="ygV-sQ-MdW"/>
+            </connections>
+        </view>
+    </objects>
+</document>

Riot/Modules/MatrixKit/Views/RoomTitle/MXKRoomTitleViewWithTopic.h

@@ -0,0 +1,36 @@
+/*
+ Copyright 2015 OpenMarket Ltd
+ 
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ 
+ http://www.apache.org/licenses/LICENSE-2.0
+ 
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import "MXKRoomTitleView.h"
+
+/**
+ 'MXKRoomTitleViewWithTopic' inherits 'MXKRoomTitleView' to add an editable room topic field.
+ */
+@interface MXKRoomTitleViewWithTopic : MXKRoomTitleView <UIGestureRecognizerDelegate>{
+}
+
+@property (weak, nonatomic) IBOutlet UITextField *topicTextField;
+
+@property (nonatomic) BOOL hiddenTopic;
+
+/**
+ Stop topic animation.
+ 
+ @return YES if the animation has been stopped.
+ */
+- (BOOL)stopTopicAnimation;
+
+@end

Riot/Modules/MatrixKit/Views/RoomTitle/MXKRoomTitleViewWithTopic.m

@@ -0,0 +1,520 @@
+/*
+ Copyright 2015 OpenMarket Ltd
+ Copyright 2017 Vector Creations Ltd
+ Copyright 2018 New Vector Ltd
+ 
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ 
+ http://www.apache.org/licenses/LICENSE-2.0
+ 
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import "MXKRoomTitleViewWithTopic.h"
+
+#import "MXKConstants.h"
+
+#import "NSBundle+MatrixKit.h"
+#import "MXRoom+Sync.h"
+
+#import "MXKSwiftHeader.h"
+
+@interface MXKRoomTitleViewWithTopic ()
+{
+    id roomTopicListener;
+    
+    // the topic can be animated if it is longer than the screen size
+    UIScrollView* scrollView;
+    UILabel* label;
+    UIView* topicTextFieldMaskView;
+    
+    // do not start the topic animation asap
+    NSTimer * animationTimer;
+}
+@end
+
+@implementation MXKRoomTitleViewWithTopic
+
++ (UINib *)nib
+{
+    return [UINib nibWithNibName:NSStringFromClass([MXKRoomTitleViewWithTopic class])
+                          bundle:[NSBundle bundleForClass:[MXKRoomTitleViewWithTopic class]]];
+}
+
+- (void)awakeFromNib
+{
+    [super awakeFromNib];
+    
+    // Add an accessory view to the text view in order to retrieve keyboard view.
+    self.topicTextField.inputAccessoryView = inputAccessoryView;
+    
+    self.displayNameTextField.returnKeyType = UIReturnKeyNext;
+    self.topicTextField.enabled = NO;
+    self.topicTextField.returnKeyType = UIReturnKeyDone;
+    self.hiddenTopic = YES;
+}
+
+- (void)refreshDisplay
+{
+    [super refreshDisplay];
+    
+    if (self.mxRoom)
+    {
+        // Remove new line characters
+        NSString *topic = [MXTools stripNewlineCharacters:self.mxRoom.summary.topic];
+        // replace empty string by nil: avoid having the placeholder when there is no topic
+        self.topicTextField.text = (topic.length ? topic : nil);
+    }
+    else
+    {
+        self.topicTextField.text = nil;
+    }
+    
+    self.hiddenTopic = (!self.topicTextField.text.length);
+}
+
+- (void)destroy
+{
+    // stop any animation
+    [self stopTopicAnimation];
+    
+    [super destroy];
+}
+
+- (void)dismissKeyboard
+{
+    // Hide the keyboard
+    [self.topicTextField resignFirstResponder];
+    
+    // restart the animation
+    [self stopTopicAnimation];
+    
+    [super dismissKeyboard];
+}
+
+#pragma mark -
+
+- (void)setMxRoom:(MXRoom *)mxRoom
+{
+    // Make sure we can access synchronously to self.mxRoom and mxRoom data
+    // to avoid race conditions
+    MXWeakify(self);
+    [mxRoom.mxSession preloadRoomsData:self.mxRoom ? @[self.mxRoom.roomId, mxRoom.roomId] : @[mxRoom.roomId] onComplete:^{
+        MXStrongifyAndReturnIfNil(self);
+
+        // Check whether the room is actually changed
+        if (self.mxRoom != mxRoom)
+        {
+            // Remove potential listener
+            if (self->roomTopicListener && self.mxRoom)
+            {
+                MXWeakify(self);
+                [self.mxRoom liveTimeline:^(MXEventTimeline *liveTimeline) {
+                    MXStrongifyAndReturnIfNil(self);
+
+                    [liveTimeline removeListener:self->roomTopicListener];
+                    self->roomTopicListener = nil;
+                }];
+            }
+
+            if (mxRoom)
+            {
+                // Register a listener to handle messages related to room name
+                self->roomTopicListener = [mxRoom listenToEventsOfTypes:@[kMXEventTypeStringRoomTopic] onEvent:^(MXEvent *event, MXTimelineDirection direction, MXRoomState *roomState) {
+
+                    // Consider only live events
+                    if (direction == MXTimelineDirectionForwards)
+                    {
+                        [self refreshDisplay];
+                    }
+                }];
+            }
+        }
+
+        super.mxRoom = mxRoom;
+    }];
+}
+
+- (void)setEditable:(BOOL)editable
+{
+    self.topicTextField.enabled = editable;
+    
+    super.editable = editable;
+}
+
+- (void)setHiddenTopic:(BOOL)hiddenTopic
+{
+    [self stopTopicAnimation];
+    if (hiddenTopic)
+    {
+        self.topicTextField.hidden = YES;
+        self.displayNameTextFieldTopConstraint.constant = 10;
+    }
+    else
+    {
+        self.topicTextField.hidden = NO;
+        self.displayNameTextFieldTopConstraint.constant = 0;
+    }
+}
+
+- (BOOL)isEditing
+{
+    return (super.isEditing || self.topicTextField.isEditing);
+}
+
+#pragma mark -
+
+// start with delay
+- (void)startTopicAnimation
+{
+    // stop any pending timer
+    if (animationTimer)
+    {
+        [animationTimer invalidate];
+        animationTimer = nil;
+    }
+    
+    // already animated the topic
+    if (scrollView)
+    {
+        return;
+    }
+    
+    // compute the text width
+    UIFont* font = self.topicTextField.font;
+    
+    // see font description
+    if (!font)
+    {
+        font = [UIFont systemFontOfSize:12];
+    }
+    
+    NSDictionary *attributes = @{NSFontAttributeName: font};
+    
+    CGSize stringSize = CGSizeMake(CGFLOAT_MAX, self.topicTextField.frame.size.height);
+    
+    stringSize  = [self.topicTextField.text boundingRectWithSize:stringSize
+                                                         options:NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading
+                                                      attributes:attributes
+                                                         context:nil].size;
+    
+    // does not need to animate the text
+    if (stringSize.width < self.topicTextField.frame.size.width)
+    {
+        return;
+    }
+    
+    // put the text in a scrollView to animat it
+    scrollView = [[UIScrollView alloc] initWithFrame: self.topicTextField.frame];
+    label = [[UILabel alloc] initWithFrame:self.topicTextField.frame];
+    label.text = self.topicTextField.text;
+    label.textColor = self.topicTextField.textColor;
+    label.font = self.topicTextField.font;
+    
+    // move to the top left
+    CGRect topicTextFieldFrame = self.topicTextField.frame;
+    topicTextFieldFrame.origin = CGPointZero;
+    label.frame = topicTextFieldFrame;
+    
+    self.topicTextField.hidden = YES;
+    [scrollView addSubview:label];
+    [self insertSubview:scrollView belowSubview:topicTextFieldMaskView];
+    
+    // update the size
+    [label sizeToFit];
+    
+    // offset
+    CGPoint offset = scrollView.contentOffset;
+    offset.x = label.frame.size.width - scrollView.frame.size.width;
+    
+    // duration (magic computation to give more time if the text is longer)
+    CGFloat duration  = label.frame.size.width / scrollView.frame.size.width * 3;
+    
+    // animate the topic once to display its full content
+    [UIView animateWithDuration:duration delay:0 options:UIViewAnimationOptionAutoreverse | UIViewAnimationOptionCurveLinear animations:^{
+        [self->scrollView setContentOffset:offset animated:NO];
+    } completion:^(BOOL finished)
+    {
+        [self stopTopicAnimation];
+    }];
+}
+
+- (BOOL)stopTopicAnimation
+{
+    // stop running timers
+    if (animationTimer)
+    {
+        [animationTimer invalidate];
+        animationTimer = nil;
+    }
+    
+    // if there is an animation is progress
+    if (scrollView)
+    {
+        self.topicTextField.hidden = NO;
+        
+        [scrollView.layer removeAllAnimations];
+        [scrollView removeFromSuperview];
+        scrollView = nil;
+        label = nil;
+        
+        [self addSubview:self.topicTextField];
+        
+        // must be done to be able to restart the animation
+        // the Z order is not kept
+        [self bringSubviewToFront:topicTextFieldMaskView];
+        
+        return YES;
+    }
+    
+    return NO;
+}
+
+- (void)editTopic
+{
+    [self stopTopicAnimation];
+    
+    dispatch_async(dispatch_get_main_queue(), ^{
+        [self.topicTextField becomeFirstResponder];
+    });
+}
+
+- (void)layoutSubviews
+{
+    // add a mask to trap the tap events
+    // it is faster (and simpliest) than subclassing the scrollview or the textField
+    // any other gesture could also be trapped here
+    if (!topicTextFieldMaskView)
+    {
+        topicTextFieldMaskView = [[UIView alloc]  initWithFrame:self.topicTextField.frame];
+        topicTextFieldMaskView.backgroundColor = [UIColor clearColor];
+        [self addSubview:topicTextFieldMaskView];
+        
+        // tap -> switch to text edition
+        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(editTopic)];
+        [tap setNumberOfTouchesRequired:1];
+        [tap setNumberOfTapsRequired:1];
+        [tap setDelegate:self];
+        [topicTextFieldMaskView addGestureRecognizer:tap];
+        
+        // long tap -> animate the topic
+        UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(startTopicAnimation)];
+        [topicTextFieldMaskView addGestureRecognizer:longPress];
+    }
+    
+    
+    // mother class call
+    [super layoutSubviews];
+}
+
+- (void)setFrame:(CGRect)frame
+{
+    // mother class call
+    [super setFrame:frame];
+    
+    // stop any running animation if the frame is updated (screen rotation for example)
+    if (!CGRectEqualToRect(CGRectIntegral(frame), CGRectIntegral(self.frame)))
+    {
+        // stop any running application
+        [self stopTopicAnimation];
+    }
+    
+    // update the mask frame
+    if (self.topicTextField.hidden)
+    {
+        topicTextFieldMaskView.frame = CGRectZero;
+    }
+    else
+    {
+        topicTextFieldMaskView.frame = self.topicTextField.frame;
+    }
+    
+    // topicTextField switches becomes the first responder or it is not anymore the first responder
+    if (self.topicTextField.isFirstResponder != (topicTextFieldMaskView.hidden))
+    {
+        topicTextFieldMaskView.hidden = self.topicTextField.isFirstResponder;
+        
+        // move topicTextFieldMaskView to the foreground
+        // when topicTextField has been the first responder, it lets a view over topicTextFieldMaskView
+        // so restore the expected Z order
+        if (!topicTextFieldMaskView.hidden)
+        {
+            [self bringSubviewToFront:topicTextFieldMaskView];
+        }
+    }
+}
+
+#pragma mark - UITextField delegate
+
+- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
+{
+    // check if the deleaget allows the edition
+    if (!self.delegate || [self.delegate roomTitleViewShouldBeginEditing:self])
+    {
+        NSString *alertMsg = nil;
+        
+        if (textField == self.displayNameTextField)
+        {
+            // Check whether the user has enough power to rename the room
+            MXRoomPowerLevels *powerLevels = self.mxRoom.dangerousSyncState.powerLevels;
+            NSInteger userPowerLevel = [powerLevels powerLevelOfUserWithUserID:self.mxRoom.mxSession.myUser.userId];
+            if (userPowerLevel >= [powerLevels minimumPowerLevelForSendingEventAsStateEvent:kMXEventTypeStringRoomName])
+            {
+                // Only the room name is edited here, update the text field with the room name
+                textField.text = self.mxRoom.summary.displayname;
+                textField.backgroundColor = [UIColor whiteColor];
+            }
+            else
+            {
+                alertMsg = [MatrixKitL10n roomErrorNameEditionNotAuthorized];
+            }
+            
+            // Check whether the user is allowed to change room topic
+            if (userPowerLevel >= [powerLevels minimumPowerLevelForSendingEventAsStateEvent:kMXEventTypeStringRoomTopic])
+            {
+                // Show topic text field even if the current value is nil
+                self.hiddenTopic = NO;
+                if (alertMsg)
+                {
+                    // Here the user can only update the room topic, switch on room topic field (without displaying alert)
+                    alertMsg = nil;
+                    [self.topicTextField becomeFirstResponder];
+                    return NO;
+                }
+            }
+        }
+        else if (textField == self.topicTextField)
+        {
+            // Check whether the user has enough power to edit room topic
+            MXRoomPowerLevels *powerLevels = self.mxRoom.dangerousSyncState.powerLevels;
+            NSInteger userPowerLevel = [powerLevels powerLevelOfUserWithUserID:self.mxRoom.mxSession.myUser.userId];
+            if (userPowerLevel >= [powerLevels minimumPowerLevelForSendingEventAsStateEvent:kMXEventTypeStringRoomTopic])
+            {
+                textField.backgroundColor = [UIColor whiteColor];
+                [self stopTopicAnimation];
+            }
+            else
+            {
+                alertMsg = [MatrixKitL10n roomErrorTopicEditionNotAuthorized];
+            }
+        }
+        
+        if (alertMsg)
+        {
+            // Alert user
+            __weak typeof(self) weakSelf = self;
+            if (currentAlert)
+            {
+                [currentAlert dismissViewControllerAnimated:NO completion:nil];
+            }
+            currentAlert = [UIAlertController alertControllerWithTitle:nil message:alertMsg preferredStyle:UIAlertControllerStyleAlert];
+            
+            [currentAlert addAction:[UIAlertAction actionWithTitle:[MatrixKitL10n cancel]
+                                                             style:UIAlertActionStyleDefault
+                                                           handler:^(UIAlertAction * action) {
+                                                               
+                                                               typeof(self) self = weakSelf;
+                                                               self->currentAlert = nil;
+                                                               
+                                                           }]];
+            
+            [self.delegate roomTitleView:self presentAlertController:currentAlert];
+            return NO;
+        }
+        return YES;
+    }
+    else
+    {
+        return NO;
+    }
+}
+
+- (void)textFieldDidEndEditing:(UITextField *)textField
+{
+    if (textField == self.topicTextField)
+    {
+        textField.backgroundColor = [UIColor clearColor];
+        
+        NSString *topic = textField.text;
+        if ((topic.length || self.mxRoom.summary.topic.length) && [topic isEqualToString:self.mxRoom.summary.topic] == NO)
+        {
+            if ([self.delegate respondsToSelector:@selector(roomTitleView:isSaving:)])
+            {
+                [self.delegate roomTitleView:self isSaving:YES];
+            }
+            __weak typeof(self) weakSelf = self;
+            [self.mxRoom setTopic:topic success:^{
+                
+                if (weakSelf)
+                {
+                    typeof(weakSelf)strongSelf = weakSelf;
+                    if ([strongSelf.delegate respondsToSelector:@selector(roomTitleView:isSaving:)])
+                    {
+                        [strongSelf.delegate roomTitleView:strongSelf isSaving:NO];
+                    }
+                    
+                    // Hide topic field if empty
+                    strongSelf.hiddenTopic = !textField.text.length;
+                }
+                
+            } failure:^(NSError *error) {
+                
+                if (weakSelf)
+                {
+                    typeof(weakSelf)strongSelf = weakSelf;
+                    if ([strongSelf.delegate respondsToSelector:@selector(roomTitleView:isSaving:)])
+                    {
+                        [strongSelf.delegate roomTitleView:strongSelf isSaving:NO];
+                    }
+                    
+                    // Revert change
+                    NSString *topic = [MXTools stripNewlineCharacters:strongSelf.mxRoom.summary.topic];
+                    textField.text = (topic.length ? topic : nil);
+                    
+                    // Hide topic field if empty
+                    strongSelf.hiddenTopic = !textField.text.length;
+                    
+                    MXLogDebug(@"[MXKRoomTitleViewWithTopic] Topic room change failed");
+                    // Notify MatrixKit user
+                    NSString *myUserId = strongSelf.mxRoom.mxSession.myUser.userId;
+                    [[NSNotificationCenter defaultCenter] postNotificationName:kMXKErrorNotification object:error userInfo:myUserId ? @{kMXKErrorUserIdKey: myUserId} : nil];
+                }
+                
+            }];
+        }
+        else
+        {
+            // Hide topic field if empty
+            self.hiddenTopic = !topic.length;
+        }
+    }
+    else
+    {
+        // Let super handle displayName text field
+        [super textFieldDidEndEditing:textField];
+    }
+}
+
+- (BOOL)textFieldShouldReturn:(UITextField*) textField
+{
+    if (textField == self.displayNameTextField)
+    {
+        // "Next" key has been pressed
+        [self.topicTextField becomeFirstResponder];
+    }
+    else
+    {
+        // "Done" key has been pressed
+        [textField resignFirstResponder];
+    }
+    return YES;
+}
+
+
+@end

Riot/Modules/MatrixKit/Views/RoomTitle/MXKRoomTitleViewWithTopic.xib

@@ -0,0 +1,53 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="11762" systemVersion="16C67" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES">
+    <device id="retina4_7" orientation="portrait">
+        <adaptation id="fullscreen"/>
+    </device>
+    <dependencies>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="11757"/>
+        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
+    </dependencies>
+    <objects>
+        <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner"/>
+        <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
+        <view contentMode="scaleToFill" id="BkF-x3-7fX" customClass="MXKRoomTitleViewWithTopic">
+            <rect key="frame" x="0.0" y="0.0" width="600" height="44"/>
+            <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+            <subviews>
+                <textField opaque="NO" clipsSubviews="YES" contentMode="scaleToFill" contentHorizontalAlignment="left" contentVerticalAlignment="center" placeholder="Room Name" textAlignment="center" minimumFontSize="14" translatesAutoresizingMaskIntoConstraints="NO" id="6uH-I3-RQg">
+                    <rect key="frame" x="0.0" y="0.0" width="600" height="21"/>
+                    <color key="backgroundColor" red="0.0" green="0.0" blue="0.0" alpha="0.0" colorSpace="custom" customColorSpace="sRGB"/>
+                    <fontDescription key="fontDescription" type="system" pointSize="17"/>
+                    <textInputTraits key="textInputTraits" returnKeyType="next"/>
+                    <connections>
+                        <outlet property="delegate" destination="BkF-x3-7fX" id="xX7-jB-9va"/>
+                    </connections>
+                </textField>
+                <textField opaque="NO" clipsSubviews="YES" contentMode="scaleToFill" contentHorizontalAlignment="left" contentVerticalAlignment="center" placeholder="Topic" textAlignment="center" minimumFontSize="17" translatesAutoresizingMaskIntoConstraints="NO" id="Cb9-hb-6f0">
+                    <rect key="frame" x="0.0" y="24" width="600" height="16"/>
+                    <color key="backgroundColor" red="0.0" green="0.0" blue="0.0" alpha="0.0" colorSpace="custom" customColorSpace="sRGB"/>
+                    <fontDescription key="fontDescription" type="system" pointSize="13"/>
+                    <textInputTraits key="textInputTraits" returnKeyType="done"/>
+                    <connections>
+                        <outlet property="delegate" destination="BkF-x3-7fX" id="8qe-OH-aKS"/>
+                    </connections>
+                </textField>
+            </subviews>
+            <color key="backgroundColor" red="0.0" green="0.0" blue="0.0" alpha="0.0" colorSpace="custom" customColorSpace="sRGB"/>
+            <constraints>
+                <constraint firstAttribute="bottom" secondItem="Cb9-hb-6f0" secondAttribute="bottom" constant="4" id="1N3-4y-mDx"/>
+                <constraint firstAttribute="trailing" secondItem="Cb9-hb-6f0" secondAttribute="trailing" id="G6O-Le-cFA"/>
+                <constraint firstItem="Cb9-hb-6f0" firstAttribute="leading" secondItem="BkF-x3-7fX" secondAttribute="leading" id="NJY-h8-w2I"/>
+                <constraint firstItem="6uH-I3-RQg" firstAttribute="top" secondItem="BkF-x3-7fX" secondAttribute="top" id="Piq-rp-Pae"/>
+                <constraint firstAttribute="trailing" secondItem="6uH-I3-RQg" secondAttribute="trailing" id="WT3-JF-1GG"/>
+                <constraint firstItem="6uH-I3-RQg" firstAttribute="leading" secondItem="BkF-x3-7fX" secondAttribute="leading" id="czp-h4-Nl6"/>
+            </constraints>
+            <freeformSimulatedSizeMetrics key="simulatedDestinationMetrics"/>
+            <connections>
+                <outlet property="displayNameTextField" destination="6uH-I3-RQg" id="MfX-LQ-C2K"/>
+                <outlet property="displayNameTextFieldTopConstraint" destination="Piq-rp-Pae" id="jnL-Hz-TWn"/>
+                <outlet property="topicTextField" destination="Cb9-hb-6f0" id="uRc-er-1Fq"/>
+            </connections>
+        </view>
+    </objects>
+</document>