update

ios/Classes/1.0/FLBFactory.m

@@ -23,17 +23,19 @@
  */
 
 #import "FLBFactory.h"
+#import "FLBFlutterViewContainer.h"
+#import "FLBFlutterApplication.h"
 
 @implementation FLBFactory
 
 - (id<FLBFlutterApplicationInterface>)createApplication:(id<FLB2Platform>)platform
 {
-    
+    return FLBFlutterApplication.new;
 }
 
-- (id<FLB2FlutterProvider>)createFlutterProvider:(id<FLB2Platform>)platform
+- (id<FLBFlutterContainer>)createFlutterContainer
 {
-    
+    return FLBFlutterViewContainer.new;
 }
 
 @end

ios/Classes/1.0/FLBFlutterApplication.h

@@ -23,13 +23,14 @@
  */
 
 #import <Foundation/Foundation.h>
-#import <Flutter/Flutter.h>
+
 
 #import "FLBFlutterApplicationInterface.h"
 
 NS_ASSUME_NONNULL_BEGIN
 @interface FLBFlutterApplication : NSObject<FLBFlutterApplicationInterface>
 
+
 @end
 
 NS_ASSUME_NONNULL_END

ios/Classes/1.0/FLBFlutterApplication.m

@@ -23,47 +23,36 @@
  */
 
 #import "FLBFlutterApplication.h"
+#import "FlutterBoost.h"
 #import "FLBFlutterContainerManager.h"
-#import "FLBFlutterEngine.h"
+#import "FLBViewProviderFactory.h"
 
 @interface FLBFlutterApplication()
 @property (nonatomic,strong) FLBFlutterContainerManager *manager;
-@property (nonatomic,strong) id<FLB2FlutterProvider> viewProvider;
+@property (nonatomic,strong) id<FLBFlutterViewProvider> viewProvider;
+
+@property (nonatomic,assign) BOOL isRendering;
 @property (nonatomic,assign) BOOL isRunning;
 @end
 
 
 @implementation FLBFlutterApplication
 
-+ (FLBFlutterApplication *)sharedApplication
-{
-    static FLBFlutterApplication *instance = nil;
-    static dispatch_once_t onceToken;
-    dispatch_once(&onceToken, ^{
-        instance = [self new];
-    });
-    return instance;
-}
-
 - (BOOL)isRunning
 {
     return _isRunning;
 }
 
-- (id)flutterProvider
-{
-    return _viewProvider;
-}
-
-- (void)startFlutterWithPlatform:(id<FLB2Platform>)platform
-                         onStart:(void (^)(id<FlutterBinaryMessenger,FlutterTextureRegistry,FlutterPluginRegistry> _Nonnull))callback
+- (void)startFlutterWithPlatform:(id<FLB2Platform>)platform onStart:(void (^)(id<FlutterBinaryMessenger,FlutterTextureRegistry,FlutterPluginRegistry> _Nonnull))callback
 {
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
         self.platform = platform;
-        self.viewProvider = [[FLBFlutterEngine alloc] init];
-        _isRunning = YES;
-        if(callback) callback(self.viewProvider.engine);
+        self.viewProvider = [[FLBViewProviderFactory new] createViewProviderWithPlatform:platform];
+        [self.viewProvider resume];
+        self.isRendering = YES;
+        self.isRunning = YES;
+        if(callback) callback(self.viewProvider.viewController);
     });
 }
 
@@ -85,18 +74,23 @@
     return [self flutterViewController].view;
 }
 
+- (FlutterViewController *)flutterViewController
+{
+    return self.viewProvider.viewController;
+}
+
 
-- (BOOL)contains:(FLBFlutterViewContainer  *)vc
+- (BOOL)contains:(id<FLBFlutterContainer>)vc
 {
     return [_manager contains:vc];
 }
 
-- (void)addUniqueViewController:(FLBFlutterViewContainer  *)vc
+- (void)addUniqueViewController:(id<FLBFlutterContainer>)vc
 {
     return [_manager addUnique:vc];
 }
 
-- (void)removeViewController:(FLBFlutterViewContainer  *)vc
+- (void)removeViewController:(id<FLBFlutterContainer>)vc
 {
     return [_manager remove:vc];
 }
@@ -109,12 +103,22 @@
 
 - (void)pause
 {
+    if(!_isRendering) return;
+    
     [self.viewProvider pause];
+    
+    _isRendering = NO;
+    
 }
 
 - (void)resume
 {
+    if(_isRendering) return;
+    
     [self.viewProvider resume];
+    
+    _isRendering = YES;
+    
 }
 
 - (void)inactive
@@ -122,9 +126,10 @@
     [self.viewProvider inactive];
 }
 
-- (FlutterViewController *)flutterViewController
+- (void)setAccessibilityEnable:(BOOL)enable
 {
-    return self.flutterProvider.engine.viewController;
+    [self.viewProvider setAccessibilityEnable:enable];
 }
 
+
 @end

ios/Classes/1.0/FLBFlutterEngine.h

@@ -23,11 +23,15 @@
  */
 
 #import <Foundation/Foundation.h>
-#import "FLBFlutterProvider.h"
+#import "FLBFlutterViewProvider.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
-@interface FLBFlutterEngine : NSObject<FLBFlutterProvider>
+#if RELEASE_1_0
+
+@interface FLBFlutterEngine : NSObject<FLBFlutterViewProvider>
 @end
 
+#endif
+
 NS_ASSUME_NONNULL_END

ios/Classes/1.0/FLBFlutterEngine.m

@@ -24,12 +24,13 @@
 
 #import "FLBFlutterEngine.h"
 #import <Flutter/Flutter.h>
-#import "FLBFlutterViewContainer.h"
+#import "FLBFlutterViewControllerAdaptor.h"
 
+#if RELEASE_1_0
 
 @interface FLBFlutterEngine()
+@property (nonatomic,strong) FLBFlutterViewControllerAdaptor *viewController;
 @property (nonatomic,strong) FlutterEngine *engine;
-@property (nonatomic,strong)  FLBFlutterViewContainer *dummy;
 @end
 
 @implementation FLBFlutterEngine
@@ -42,14 +43,15 @@
     if (self = [super init]) {
         _engine = [[FlutterEngine alloc] initWithName:@"io.flutter" project:nil];
         [_engine runWithEntrypoint:nil];
-        _dummy = [[FLBFlutterViewContainer alloc] initWithEngine:_engine
-                                                       nibName:nil
-                                                        bundle:nil];
+        _viewController = [[FLBFlutterViewControllerAdaptor alloc] initWithEngine:_engine
+                                                                          nibName:nil
+                                                                           bundle:nil];
+        [_viewController view];
         Class clazz = NSClassFromString(@"GeneratedPluginRegistrant");
         if (clazz) {
             if ([clazz respondsToSelector:NSSelectorFromString(@"registerWithRegistry:")]) {
                 [clazz performSelector:NSSelectorFromString(@"registerWithRegistry:")
-                            withObject:_engine];
+                            withObject:_viewController];
             }
         }
     }
@@ -58,14 +60,23 @@
 #pragma clang diagnostic pop
 }
 
+- (FlutterViewController *)viewController
+{
+    return _viewController;
+}
+
 - (void)pause
 {
-    [[_engine lifecycleChannel] sendMessage:@"AppLifecycleState.pause"];
+    //TODO: [[_engine.get() lifecycleChannel] sendMessage:@"AppLifecycleState.paused"];
+    [self.viewController boost_viewWillDisappear:NO];
+    [self.viewController boost_viewDidDisappear:NO];
 }
 
 - (void)resume
 {
-    [[_engine lifecycleChannel] sendMessage:@"AppLifecycleState.resume"];
+    //TODO:   [[_engine.get() lifecycleChannel] sendMessage:@"AppLifecycleState.resumed"];
+    [self.viewController boost_viewWillAppear:NO];
+    [self.viewController boost_viewDidAppear:NO];
 }
 
 - (void)inactive
@@ -73,31 +84,10 @@
     [[_engine lifecycleChannel] sendMessage:@"AppLifecycleState.inactive"];
 }
 
-
-- (FlutterEngine *)engine
-{
-    return _engine;
-}
-
-- (void)atacheToViewController:(FlutterViewController *)vc
-{
-    if(_engine.viewController != vc){
-        _engine.viewController = vc;
-    }
-}
-
-- (void)detach
-{
-    if(_engine.viewController != _dummy){
-        _engine.viewController = _dummy;
-    }
-}
-
-- (void)prepareEngineIfNeeded
+- (void)setAccessibilityEnable:(BOOL)enable
 {
-    [self detach];
-    [_dummy surfaceUpdated:YES];
+    self.viewController.accessibilityEnable = enable;
 }
-
 @end
 
+#endif

ios/Classes/1.0/FLBFlutterEngineOld.h

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import <Foundation/Foundation.h>
+#import "FLBFlutterViewProvider.h"
+#import "FLBPlatform.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface FLBFlutterEngineOld : NSObject<FLBFlutterViewProvider>
+
+- (instancetype)initWithPlatform:(id<FLBPlatform>)platform;
+
+@end
+
+NS_ASSUME_NONNULL_END

ios/Classes/1.0/FLBFlutterEngineOld.m

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import "FLBFlutterEngineOld.h"
+#import "FLBFlutterViewControllerAdaptor.h"
+#import <objc/runtime.h>
+
+@interface FLBFlutterEngineOld()
+@property (nonatomic,strong) FLBFlutterViewControllerAdaptor *viewController;
+@end
+
+@implementation FLBFlutterEngineOld
+
+- (instancetype)initWithPlatform:(id<FLBPlatform>)platform
+{
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
+    
+    if (self = [super init]) {
+
+        Class class = [FLBFlutterViewControllerAdaptor class];
+        SEL originalSelector = @selector(onAccessibilityStatusChanged:);
+        SEL swizzledSelector = @selector(fixed_onAccessibilityStatusChanged:);
+        Method originalMethod = class_getInstanceMethod(class, originalSelector);
+        Method swizzledMethod = class_getInstanceMethod(class, swizzledSelector);
+        method_exchangeImplementations(originalMethod, swizzledMethod);
+        
+        _viewController = [FLBFlutterViewControllerAdaptor new];
+        if([platform respondsToSelector:@selector(accessibilityEnable)]){
+            _viewController.accessibilityEnable = [platform accessibilityEnable];
+        }else{
+            _viewController.accessibilityEnable = YES;
+        }
+     
+        [_viewController view];
+        Class clazz = NSClassFromString(@"GeneratedPluginRegistrant");
+        if (clazz) {
+            if ([clazz respondsToSelector:NSSelectorFromString(@"registerWithRegistry:")]) {
+                [clazz performSelector:NSSelectorFromString(@"registerWithRegistry:")
+                            withObject:_viewController];
+            }
+        }
+    }
+    
+    return self;
+#pragma clang diagnostic pop
+}
+
+- (FlutterViewController *)viewController
+{
+    return _viewController;
+}
+
+- (void)pause
+{
+    [self.viewController boost_viewWillDisappear:NO];
+    [self.viewController boost_viewDidDisappear:NO];
+}
+
+- (void)resume
+{
+    [self.viewController boost_viewWillAppear:NO];
+    [self.viewController boost_viewDidAppear:NO];
+}
+
+- (void)inactive
+{
+    NSString *channel = @"flutter/lifecycle";
+    NSString *message = @"AppLifecycleState.inactive";
+    NSData *data = [[FlutterStringCodec sharedInstance] encode:message];
+    [self.viewController sendOnChannel:channel message:data];
+}
+
+- (void)resumeFlutterOnly
+{
+    NSString *channel = @"flutter/lifecycle";
+    NSString *message = @"AppLifecycleState.resumed";
+    NSData *data = [[FlutterStringCodec sharedInstance] encode:message];
+    [self.viewController sendOnChannel:channel message:data];
+}
+
+- (void)setAccessibilityEnable:(BOOL)enable
+{
+    self.viewController.accessibilityEnable = enable;
+}
+
+@end

ios/Classes/1.0/FLBFlutterViewContainer.h

@@ -23,25 +23,12 @@
  */
 
 #import <UIKit/UIKit.h>
-#import <Flutter/Flutter.h>
+
 #import "FLBFlutterContainer.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
-@interface FLBFlutterViewContainer  : FlutterViewController
-
-@property (nonatomic,copy,readonly) NSString *name;
-@property (nonatomic,strong,readonly) NSDictionary *params;
-@property (nonatomic,copy,readonly) NSString *uniqueIDString;
-
-/*
- You must call this one time to set flutter page name
- and params.
- */
-- (void)setName:(NSString *)name params:(NSDictionary *)params;
-
-
-- (void)surfaceUpdated:(BOOL)appeared;
+@interface FLBFlutterViewContainer  : UIViewController<FLBFlutterContainer>
 
 @end
 

ios/Classes/1.0/FLBFlutterViewContainer.m

@@ -24,9 +24,11 @@
 
 #import "FLBFlutterViewContainer.h"
 #import "FLBFlutterApplication.h"
+#import "FLBStackCache.h"
+#import "FLBStackCacheObjectImg.h"
+#import "FLBMemoryInspector.h"
 #import "Service_NavigationService.h"
 #import "FlutterBoostConfig.h"
-#import "FLBFlutterViewContainerManager.h"
 
 #define FLUTTER_VIEW [FLBFlutterApplication sharedApplication].flutterViewController.view
 #define FLUTTER_VC [FLBFlutterApplication sharedApplication].flutterViewController
@@ -35,30 +37,13 @@
 @interface FLBFlutterViewContainer  ()
 @property (nonatomic,copy,readwrite) NSString *name;
 @property (nonatomic,strong,readwrite) NSDictionary *params;
+@property (nonatomic,strong) UIImageView *screenShotView;
 @property (nonatomic,assign) long long identifier;
+@property (nonatomic,assign) BOOL interactiveGestureActive;
 @end
 
 @implementation FLBFlutterViewContainer
 
-- (instancetype)init
-{
-    [FLUTTER_APP.flutterProvider prepareEngineIfNeeded];
-    if(self = [super initWithEngine:FLUTTER_APP.flutterProvider.engine
-                            nibName:nil
-                             bundle:nil]){
-        [self _setup];
-    }
-    return self;
-}
-
-- (instancetype)initWithCoder:(NSCoder *)aDecoder{
-    if (self = [super initWithCoder: aDecoder]) {
-        NSAssert(NO, @"unsupported init method!");
-        [self _setup];
-    }
-    return self;
-}
-
 - (void)setName:(NSString *)name params:(NSDictionary *)params
 {
     if(!_name && name){
@@ -83,7 +68,7 @@ static NSUInteger kInstanceCounter = 0;
 {
     kInstanceCounter++;
     if(kInstanceCounter == 1){
-//        [FLUTTER_APP resume];
+        [FLUTTER_APP resume];
     }
 }
 
@@ -91,7 +76,8 @@ static NSUInteger kInstanceCounter = 0;
 {
     kInstanceCounter--;
     if([self.class instanceCounter] == 0){
-//        [[FLBFlutterApplication sharedApplication] pause];
+        [[FLBStackCache sharedInstance] clear];
+        [[FLBFlutterApplication sharedApplication] pause];
     }
 }
 
@@ -105,6 +91,43 @@ static NSUInteger kInstanceCounter = 0;
     static long long sCounter = 0;
     _identifier = sCounter++;
     [self.class instanceCounterIncrease];
+    
+    SEL sel = @selector(flutterViewDidShow:);
+    NSString *notiName = @"flutter_boost_container_showed";
+    [NSNotificationCenter.defaultCenter addObserver:self
+                                           selector:sel
+                                               name:notiName
+                                             object:nil];
+}
+
+- (instancetype)init
+{
+    if(self = [super init]){
+        [self _setup];
+    }
+    return self;
+}
+
+- (instancetype)initWithCoder:(NSCoder *)aDecoder{
+    if (self = [super initWithCoder: aDecoder]) {
+        [self _setup];
+    }
+    return self;
+}
+
+- (void)flutterViewDidAppear:(NSDictionary *)params
+{
+    //Notify flutter view appeared.
+}
+
+- (void)flutterViewDidShow:(NSNotification *)notification
+{
+     __weak typeof(self) weakSelf = self;
+    if([notification.object isEqual: self.uniqueIDString]){
+        dispatch_async(dispatch_get_main_queue(), ^{
+            [weakSelf showFlutterView];
+        });
+    }
 }
 
 - (void)dealloc
@@ -119,6 +142,7 @@ static NSUInteger kInstanceCounter = 0;
                                                pageName:_name params:_params
                                                uniqueId:[self uniqueIDString]];
 
+    [[FLBStackCache sharedInstance] remove:self.uniqueIDString];
     [[FLBFlutterApplication sharedApplication] removeViewController:self];
     
     [self.class instanceCounterDecrease];
@@ -126,26 +150,140 @@ static NSUInteger kInstanceCounter = 0;
 
 - (void)viewDidLoad {
     [super viewDidLoad];
+    
     self.view.backgroundColor = UIColor.whiteColor;
+    
+    self.screenShotView = [[UIImageView alloc] initWithFrame:self.view.bounds];
+    self.screenShotView.backgroundColor = [UIColor whiteColor];
+    
+    [self.view addSubview:self.screenShotView];
 }
 
 #pragma mark - ScreenShots
+- (UIImage *)takeScreenShot
+{
+    CGFloat scale = 1;
+    switch ([FLBMemoryInspector.sharedInstance currentCondition]) {
+        case FLBMemoryConditionNormal:
+            scale = 2;
+            break;
+        case FLBMemoryConditionLowMemory:
+            scale = 1;
+            break;
+        case FLBMemoryConditionExtremelyLow:
+            scale = 0.75;
+            break;
+        case FLBMemoryConditionAboutToDie:
+            return [UIImage new];
+            break;
+        case FLBMemoryConditionUnknown:
+            if([[FLBMemoryInspector sharedInstance] smallMemoryDevice]){
+                scale = 1;
+            }else{
+                scale = 2;
+            }
+            break;
+    }
+    
+    self.screenShotView.opaque = YES;
+    
+    CGRect flutterBounds = self.view.bounds;
+    CGSize snapshotSize = CGSizeMake(flutterBounds.size.width ,
+                                     flutterBounds.size.height);
+    UIGraphicsBeginImageContextWithOptions(snapshotSize, NO, scale);
+    
+    [self.view drawViewHierarchyInRect:flutterBounds
+                    afterScreenUpdates:NO];
+    
+    UIImage *snapImage = UIGraphicsGetImageFromCurrentImageContext();
+    UIGraphicsEndImageContext();
+    
+    return snapImage;
+}
+
+- (void)saveScreenShot
+{
+    UIImage *snapImage = [self takeScreenShot];
+    if(snapImage){
+        FLBStackCacheObjectImg *cImg = [[FLBStackCacheObjectImg alloc] initWithImage:snapImage];
+        [[FLBStackCache sharedInstance] pushObject:cImg key:self.uniqueIDString];
+    }
+}
+
+- (void)clearCurrentScreenShotImage
+{
+    self.screenShotView.image = nil;
+}
+
+- (UIImage *)getSavedScreenShot
+{
+    FLBStackCacheObjectImg *cImg = [[FLBStackCache sharedInstance] objectForKey:self.uniqueIDString];
+    return [cImg image];
+}
+
 - (BOOL)isFlutterViewAttatched
 {
     return FLUTTER_VIEW.superview == self.view;
 }
 
-- (void)attatchFlutterEngine
+- (void)attatchFlutterView
 {
-    [FLUTTER_APP.flutterProvider prepareEngineIfNeeded];
-    [FLUTTER_APP.flutterProvider atacheToViewController:self];
+    if([self isFlutterViewAttatched]) return;
+    
+    [FLUTTER_VC willMoveToParentViewController:nil];
+    [FLUTTER_VC removeFromParentViewController];
+    [FLUTTER_VC didMoveToParentViewController:nil];
+   
+    [FLUTTER_VC willMoveToParentViewController:self];
+    FLUTTER_VIEW.frame = self.view.bounds;
+    
+    if(!self.screenShotView.image){
+         [self.view addSubview: FLUTTER_VIEW];
+    }else{
+        [self.view insertSubview:FLUTTER_VIEW belowSubview:self.screenShotView];
+    }
+
+    [self addChildViewController:FLUTTER_VC];
+    [FLUTTER_VC didMoveToParentViewController:self];
 }
 
-- (void)detatchFlutterEngine
+- (BOOL)showSnapShotVew
 {
-    [FLUTTER_APP.flutterProvider detach];
+    self.screenShotView.image = [self getSavedScreenShot];
+   
+    if([self isFlutterViewAttatched]){
+        NSUInteger fIdx = [self.view.subviews indexOfObject:FLUTTER_VIEW];
+        NSUInteger sIdx = [self.view.subviews indexOfObject:self.screenShotView];
+        if(fIdx > sIdx){
+            [self.view insertSubview:FLUTTER_VIEW
+                             atIndex:0];
+        }
+    }else{
+        
+    }
+    
+    return self.screenShotView.image != nil;
 }
 
+- (void)showFlutterView
+{
+    if(FLUTTER_VIEW.superview != self.view) return;
+    
+    if([self isFlutterViewAttatched] ){
+        NSUInteger fIdx = [self.view.subviews indexOfObject:FLUTTER_VIEW];
+        NSUInteger sIdx = [self.view.subviews indexOfObject:self.screenShotView];
+        self.screenShotView.backgroundColor = UIColor.clearColor;
+        if(sIdx > fIdx){
+            [self.view insertSubview:self.screenShotView belowSubview:FLUTTER_VIEW];
+            [self flutterViewDidAppear:@{@"uid":self.uniqueIDString?:@""}];
+        }
+    }
+    
+    [self clearCurrentScreenShotImage];
+    
+    //Invalidate obsolete screenshot.
+    [FLBStackCache.sharedInstance invalidate:self.uniqueIDString];
+}
 
 #pragma mark - Life circle methods
 
@@ -157,18 +295,19 @@ static NSUInteger kInstanceCounter = 0;
 
 - (void)viewWillAppear:(BOOL)animated
 {
-    if([FLUTTER_APP contains:self]){
-        [self detatchFlutterEngine];
-    }else{
-        [self attatchFlutterEngine];
+    if(self.navigationController.interactivePopGestureRecognizer.state == UIGestureRecognizerStateBegan){
+        self.interactiveGestureActive = true;
     }
-  
-    [[FLBFlutterApplication sharedApplication] resume];
     
-    [self surfaceUpdated:YES];
+    [[FLBFlutterApplication sharedApplication] resume];
     //For new page we should attach flutter view in view will appear
     //for better performance.
- 
+    if(![[FLBFlutterApplication sharedApplication] contains:self]){
+         [self attatchFlutterView];
+    }
+    
+    [self showSnapShotVew];
+    
     [Service_NavigationService willShowPageContainer:^(NSNumber *result) {}
                                             pageName:_name
                                               params:_params
@@ -185,21 +324,49 @@ static NSUInteger kInstanceCounter = 0;
 
 - (void)viewDidAppear:(BOOL)animated
 {
-    [FLUTTER_APP addUniqueViewController:self];
-    
+    [[FLBFlutterApplication sharedApplication] resume];
+   
     //Ensure flutter view is attached.
-    [self attatchFlutterEngine];
-    [self surfaceUpdated:YES];
+    [self attatchFlutterView];
+    
     [Service_NavigationService didShowPageContainer:^(NSNumber *result) {}
                                            pageName:_name
                                              params:_params
                                            uniqueId:self.uniqueIDString];
     
+    [[FLBFlutterApplication sharedApplication] addUniqueViewController:self];
+    
     [super viewDidAppear:animated];
+ 
+    __weak typeof(self) weakSelf = self;
+    dispatch_after(dispatch_time(DISPATCH_TIME_NOW,
+                                 (int64_t)(2 * NSEC_PER_SEC)),
+                   dispatch_get_main_queue(),^{
+                       if (weakSelf.isViewLoaded && weakSelf.view.window) {
+                           // viewController is visible
+                            [weakSelf showFlutterView];
+                       }
+                   });
+    
+    self.interactiveGestureActive = NO;
 }
 
 - (void)viewWillDisappear:(BOOL)animated
 {
+    //is top.
+    if([FLUTTER_APP isTop:self.uniqueIDString]
+       && self.navigationController.interactivePopGestureRecognizer.state != UIGestureRecognizerStateBegan
+       && !self.interactiveGestureActive){
+        [self saveScreenShot];
+    }
+    
+    self.interactiveGestureActive = NO;
+   
+    self.screenShotView.image = [self getSavedScreenShot];
+    if(self.screenShotView.image){
+        [self.view bringSubviewToFront:self.screenShotView];
+    }
+   
     [Service_NavigationService willDisappearPageContainer:^(NSNumber *result) {}
                                                  pageName:_name
                                                    params:_params
@@ -210,12 +377,16 @@ static NSUInteger kInstanceCounter = 0;
 
 - (void)viewDidDisappear:(BOOL)animated
 {
-    [self detatchFlutterEngine];
     [Service_NavigationService didDisappearPageContainer:^(NSNumber *result) {}
                                                 pageName:_name
                                                   params:_params
                                                 uniqueId:self.uniqueIDString];
+    
+    [self clearCurrentScreenShotImage];
     [super viewDidDisappear:animated];
+
+    [FLUTTER_APP inactive];
+    self.interactiveGestureActive = NO;
 }
 
 #pragma mark - FLBViewControllerResultHandler
@@ -228,14 +399,5 @@ static NSUInteger kInstanceCounter = 0;
                                            params:@{}];
 }
 
-- (void)installSplashScreenViewIfNecessary {
-    //Do nothing.
-}
-
-- (BOOL)loadDefaultSplashScreenView
-{
-    return NO;
-}
-
 
 @end

ios/Classes/1.0/FLBFlutterViewControllerAdaptor.h

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import <Flutter/Flutter.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface FLBFlutterViewControllerAdaptor : FlutterViewController
+- (void)boost_viewWillAppear:(BOOL)animated;
+- (void)boost_viewDidAppear:(BOOL)animated;
+- (void)boost_viewWillDisappear:(BOOL)animated;
+- (void)boost_viewDidDisappear:(BOOL)animated;
+
+@property (nonatomic,assign) BOOL accessibilityEnable;
+
+@end
+
+NS_ASSUME_NONNULL_END

ios/Classes/1.0/FLBFlutterViewControllerAdaptor.m

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import "FLBFlutterViewControllerAdaptor.h"
+#import <objc/runtime.h>
+
+@interface FLBFlutterViewControllerAdaptor ()
+@end
+
+@implementation FLBFlutterViewControllerAdaptor
+
+- (void)viewDidLoad {
+    [super viewDidLoad];
+    self.view.backgroundColor = [UIColor whiteColor];
+    // Do any additional setup after loading the view.
+}
+
+
+- (void)viewWillAppear:(BOOL)animated
+{
+    //Left blank intentionally.
+}
+
+- (void)viewDidAppear:(BOOL)animated
+{
+   //Left blank intentionally.
+}
+
+- (void)viewWillDisappear:(BOOL)animated
+{
+    [[UIApplication sharedApplication] sendAction:@selector(resignFirstResponder) to:nil from:nil forEvent:nil];
+    //Avoid super call intentionally.
+}
+
+- (void)viewDidDisappear:(BOOL)animated
+{
+    //Avoid super call intentionally.
+     [[[UIApplication sharedApplication] keyWindow] endEditing:YES];
+}
+
+
+- (void)boost_viewWillAppear:(BOOL)animated
+{
+    [super viewWillAppear:animated];
+}
+
+- (void)boost_viewDidAppear:(BOOL)animated
+{
+    [super viewDidAppear:animated];
+}
+
+- (void)boost_viewWillDisappear:(BOOL)animated
+{
+    [super viewWillDisappear:animated];
+}
+
+- (void)boost_viewDidDisappear:(BOOL)animated
+{
+    [super viewDidDisappear:animated];
+}
+
+
+- (UIEdgeInsets)paddingEdgeInsets{
+    UIEdgeInsets edgeInsets = UIEdgeInsetsZero;
+    if (@available(iOS 11, *)) {
+        edgeInsets = UIEdgeInsetsMake(0, self.view.safeAreaInsets.left, self.view.safeAreaInsets.bottom, self.view.safeAreaInsets.right);
+    } else {
+        edgeInsets = UIEdgeInsetsZero;
+    }
+    return edgeInsets;
+}
+
+- (void)installSplashScreenViewIfNecessary {
+  //Override this to avoid unnecessary splash Screen.
+}
+
+- (void)fixed_onAccessibilityStatusChanged:(NSNotification*)notification {
+    if(self.accessibilityEnable){
+        [self fixed_onAccessibilityStatusChanged:notification];
+    }
+}
+
+
+@end

ios/Classes/1.0/FLBFlutterViewProvider.h

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import <Foundation/Foundation.h>
+
+@class FlutterViewController;
+
+NS_ASSUME_NONNULL_BEGIN
+
+#define RELEASE_1_0 0
+
+@protocol FLBFlutterViewProvider <NSObject>
+
+@required
+- (void)setAccessibilityEnable:(BOOL)enable;
+- (BOOL)accessibilityEnable;
+- (FlutterViewController *)viewController;
+- (void)pause;
+- (void)resume;
+- (void)inactive;
+
+@end
+
+NS_ASSUME_NONNULL_END

ios/Classes/1.0/FLBViewProviderFactory.h

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "FLBFlutterViewProvider.h"
+#import "FLBPlatform.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface FLBViewProviderFactory : NSObject
+
+- (id<FLBFlutterViewProvider>)createViewProvider;
+- (id<FLBFlutterViewProvider>)createViewProviderWithPlatform:(id<FLBPlatform>)platform;
+
+@end
+
+NS_ASSUME_NONNULL_END

ios/Classes/1.0/FLBViewProviderFactory.m

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import "FLBViewProviderFactory.h"
+#import "FLBFlutterEngine.h"
+#import "FLBFlutterEngineOld.h"
+#import "FLBPlatform.h"
+
+
+@implementation FLBViewProviderFactory
+
+- (id<FLBFlutterViewProvider>)createViewProviderWithPlatform:(id<FLBPlatform>)platform
+{
+#if RELEASE_1_0
+    return [FLBFlutterEngine new];
+#else
+    return [[FLBFlutterEngineOld alloc] initWithPlatform:platform];
+#endif
+}
+
+- (id<FLBFlutterViewProvider>)createViewProvider
+{
+#if RELEASE_1_0
+    return [FLBFlutterEngine new];
+#else
+    return [FLBFlutterEngineOld new];
+#endif
+}
+
+@end

ios/Classes/1.0/FlutterBoostConfig.h

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface FlutterBoostConfig : NSObject
+#pragma mark - Store first open page
+//There are some cases first page messages could be lost.
+//So we store the first page info for later usage.
++ (instancetype)sharedInstance;
+@property (nonatomic,copy) NSString *fPagename;
+@property (nonatomic,copy) NSString *fPageId;
+@property (nonatomic,strong) NSDictionary *fParams;
+- (BOOL)firstView;
+@end
+
+
+
+NS_ASSUME_NONNULL_END

ios/Classes/1.0/FlutterBoostConfig.m

+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2019 Alibaba Group
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#import "FlutterBoostConfig.h"
+
+@interface FlutterBoostConfig()
+@property (nonatomic,assign) BOOL firstView;
+
+@end
+
+@implementation FlutterBoostConfig
+
++ (instancetype)sharedInstance
+{
+    static FlutterBoostConfig *instance = nil;
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        instance = [self new];
+        instance.firstView = YES;
+    });
+    
+    return instance;
+}
+
+- (void)setFPageId:(NSString *)fPageId
+{
+    _fPageId = fPageId;
+    _firstView = NO;
+}
+
+- (BOOL)firstView
+{
+    return _firstView;
+}
+
+@end
+
+

ios/Classes/Boost/FLBAbstractFactory.h

@@ -33,10 +33,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 @protocol FLBAbstractFactory <NSObject>
 
+@required
 - (id<FLBFlutterApplicationInterface>)createApplication:(id<FLB2Platform>)platform;
-
-- (id<FLB2FlutterProvider>)createFlutterProvider:(id<FLB2Platform>)platform;
-
 - (id<FLBFlutterContainer>)createFlutterContainer;
 
 @end