Flutter iOS Embedder
FlutterKeyboardManager.h
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef FLUTTER_SHELL_PLATFORM_DARWIN_IOS_FRAMEWORK_SOURCE_FLUTTER_KEYBOARD_MANAGER_H_
6 #define FLUTTER_SHELL_PLATFORM_DARWIN_IOS_FRAMEWORK_SOURCE_FLUTTER_KEYBOARD_MANAGER_H_
7 
9 
10 #import <Foundation/NSObject.h>
11 #import <UIKit/UIKit.h>
12 
13 #include "flutter/fml/memory/weak_ptr.h"
17 
18 typedef void (^KeyEventCompleteCallback)(bool, FlutterUIPressProxy* _Nonnull)
19  API_AVAILABLE(ios(13.4));
20 
21 /**
22  * A hub that manages how key events are dispatched to various Flutter key
23  * responders, and propagates it to the superclass if the Flutter key responders
24  * do not handle it.
25  *
26  * This class manages one or more primary responders, as well as zero or more
27  * secondary responders.
28  *
29  * An event that is received by |handlePresses| is first dispatched to *all*
30  * primary responders. Each primary responder responds *asynchronously* with a
31  * boolean, indicating whether it handles the event.
32  *
33  * An event that is not handled by any primary responders is then passed to to
34  * the first secondary responder (in the chronological order of addition),
35  * which responds *synchronously* with a boolean, indicating whether it handles
36  * the event. If not, the event is passed to the next secondary responder, and
37  * so on.
38  *
39  * The event is then handed back to the |completeCallback| from the original
40  * call to |handlePresses| so that it can respond synchronously to the OS if the
41  * event was not handled by the responders. The |completeCallback| is called on
42  * the platform thread because the platform thread is blocked by a nested event
43  * loop while the response from the framework is being collected, and it needs
44  * to be called on the platform thread to unblock the thread by exiting the
45  * nested event loop.
46  *
47  * Preventing primary responders from receiving events is not supported, because
48  * in reality this class only supports two hardcoded responders
49  * (FlutterChannelKeyResponder and FlutterEmbedderKeyResponder), where the only purpose
50  * of supporting two is to maintain the legacy channel API during the
51  * deprecation window, after which the channel responder should be removed, and
52  * only one primary responder will exist.
53  */
54 @interface FlutterKeyboardManager : NSObject
55 /**
56  * Add a primary responder, which asynchronously decides whether to handle an
57  * event.
58  */
59 - (void)addPrimaryResponder:(nonnull id<FlutterKeyPrimaryResponder>)responder;
60 
61 /**
62  * Add a secondary responder, which synchronously decides whether to handle an
63  * event in order if no earlier responders handle.
64  */
65 - (void)addSecondaryResponder:(nonnull id<FlutterKeySecondaryResponder>)responder;
66 
67 /**
68  * Dispatches a key press event to all responders, gathering their responses,
69  * and then calls the |nextAction| if the event was not handled.
70  */
71 - (void)handlePress:(nonnull FlutterUIPressProxy*)press
72  nextAction:(nonnull void (^)())next API_AVAILABLE(ios(13.4));
73 @end
74 
75 #endif // FLUTTER_SHELL_PLATFORM_DARWIN_IOS_FRAMEWORK_SOURCE_FLUTTER_KEYBOARD_MANAGER_H_
FlutterKeyPrimaryResponder-p
Definition: FlutterKeyPrimaryResponder.h:19
API_AVAILABLE
UITextSmartQuotesType smartQuotesType API_AVAILABLE(ios(11.0))
FlutterKeyPrimaryResponder.h
FlutterKeySecondaryResponder-p
Definition: FlutterKeySecondaryResponder.h:17
KeyEventCompleteCallback
void(^ KeyEventCompleteCallback)(bool, FlutterUIPressProxy *_Nonnull) API_AVAILABLE(ios(13.4))
Definition: FlutterKeyboardManager.h:18
FlutterUIPressProxy
Definition: FlutterUIPressProxy.h:17
FlutterUIPressProxy.h
FlutterKeySecondaryResponder.h
FlutterKeyboardManager
Definition: FlutterKeyboardManager.h:54