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flutter_windows.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_WINDOWS_PUBLIC_FLUTTER_WINDOWS_H_
6 #define FLUTTER_SHELL_PLATFORM_WINDOWS_PUBLIC_FLUTTER_WINDOWS_H_
7
8 #include <dxgi.h>
9 #include <stddef.h>
10 #include <stdint.h>
11 #include <windows.h>
12
13 #include "flutter_export.h"
14 #include "flutter_messenger.h"
15 #include "flutter_plugin_registrar.h"
16
17 #if defined(__cplusplus)
18 extern "C" {
19 #endif
20
21 typedef void (*VoidCallback)(void* /* user data */);
22
23 // Opaque reference to a Flutter view controller.
24 struct FlutterDesktopViewController;
25 typedef struct FlutterDesktopViewController* FlutterDesktopViewControllerRef;
26
27 // Opaque reference to a Flutter window.
28 struct FlutterDesktopView;
29 typedef struct FlutterDesktopView* FlutterDesktopViewRef;
30
31 // Opaque reference to a Flutter engine instance.
32 struct FlutterDesktopEngine;
33 typedef struct FlutterDesktopEngine* FlutterDesktopEngineRef;
34
35 // The unique identifier for a view.
36 typedef int64_t FlutterDesktopViewId;
37
38 // Properties for configuring a Flutter engine instance.
39 typedef struct {
40 // The path to the flutter_assets folder for the application to be run.
41 // This can either be an absolute path or a path relative to the directory
42 // containing the executable.
43 const wchar_t* assets_path;
44
45 // The path to the icudtl.dat file for the version of Flutter you are using.
46 // This can either be an absolute path or a path relative to the directory
47 // containing the executable.
48 const wchar_t* icu_data_path;
49
50 // The path to the AOT library file for your application, if any.
51 // This can either be an absolute path or a path relative to the directory
52 // containing the executable. This can be nullptr for a non-AOT build, as
53 // it will be ignored in that case.
54 const wchar_t* aot_library_path;
55
56 // The name of the top-level Dart entrypoint function. If null or the empty
57 // string, 'main' is assumed. If a custom entrypoint is used, this parameter
58 // must specifiy the name of a top-level function in the same Dart library as
59 // the app's main() function. Custom entrypoint functions must be decorated
60 // with `@pragma('vm:entry-point')` to ensure the method is not tree-shaken
61 // by the Dart compiler.
62 const char* dart_entrypoint;
63
64 // Number of elements in the array passed in as dart_entrypoint_argv.
65 int dart_entrypoint_argc;
66
67 // Array of Dart entrypoint arguments. This is deep copied during the call
68 // to FlutterDesktopEngineCreate.
69 const char** dart_entrypoint_argv;
70
71 } FlutterDesktopEngineProperties;
72
73 // ========== View Controller ==========
74
75 // Creates a view that hosts and displays the given engine instance.
76 //
77 // This takes ownership of |engine|, so FlutterDesktopEngineDestroy should no
78 // longer be called on it, as it will be called internally when the view
79 // controller is destroyed. If creating the view controller fails, the engine
80 // will be destroyed immediately.
81 //
82 // If |engine| is not already running, the view controller will start running
83 // it automatically before displaying the window.
84 //
85 // The caller owns the returned reference, and is responsible for calling
86 // FlutterDesktopViewControllerDestroy. Returns a null pointer in the event of
87 // an error.
88 //
89 // The Win32 implementation accepts width, height with view hookup explicitly
90 // performed using the caller using HWND parenting.
91 FLUTTER_EXPORT FlutterDesktopViewControllerRef
92 FlutterDesktopViewControllerCreate(int width,
93 int height,
94 FlutterDesktopEngineRef engine);
95
96 // Shuts down the engine instance associated with |controller|, and cleans up
97 // associated state.
98 //
99 // |controller| is no longer valid after this call.
100 FLUTTER_EXPORT void FlutterDesktopViewControllerDestroy(
101 FlutterDesktopViewControllerRef controller);
102
103 // Returns the view controller's view ID.
104 FLUTTER_EXPORT FlutterDesktopViewId FlutterDesktopViewControllerGetViewId(
105 FlutterDesktopViewControllerRef view_controller);
106
107 // Returns the handle for the engine running in FlutterDesktopViewControllerRef.
108 //
109 // Its lifetime is the same as the |controller|'s.
110 FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopViewControllerGetEngine(
111 FlutterDesktopViewControllerRef controller);
112
113 // Returns the view managed by the given controller.
114 FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopViewControllerGetView(
115 FlutterDesktopViewControllerRef controller);
116
117 // Requests new frame from the engine and repaints the view.
118 FLUTTER_EXPORT void FlutterDesktopViewControllerForceRedraw(
119 FlutterDesktopViewControllerRef controller);
120
121 // Allows the Flutter engine and any interested plugins an opportunity to
122 // handle the given message.
123 //
124 // If the WindowProc was handled and further handling should stop, this returns
125 // true and |result| will be populated. |result| is not set if returning false.
126 FLUTTER_EXPORT bool FlutterDesktopViewControllerHandleTopLevelWindowProc(
127 FlutterDesktopViewControllerRef controller,
128 HWND hwnd,
129 UINT message,
130 WPARAM wparam,
131 LPARAM lparam,
132 LRESULT* result);
133
134 // ========== Engine ==========
135
136 // Creates a Flutter engine with the given properties.
137 //
138 // The caller owns the returned reference, and is responsible for calling
139 // FlutterDesktopEngineDestroy. The lifetime of |engine_properties| is required
140 // to extend only until the end of this call.
141 FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopEngineCreate(
142 const FlutterDesktopEngineProperties* engine_properties);
143
144 // Shuts down and destroys the given engine instance. Returns true if the
145 // shutdown was successful, or if the engine was not running.
146 //
147 // |engine| is no longer valid after this call.
148 FLUTTER_EXPORT bool FlutterDesktopEngineDestroy(FlutterDesktopEngineRef engine);
149
150 // Starts running the given engine instance.
151 //
152 // The entry_point parameter is deprecated but preserved for
153 // backward-compatibility. If desired, a custom Dart entrypoint function can be
154 // set in the dart_entrypoint field of the FlutterDesktopEngineProperties
155 // struct passed to FlutterDesktopEngineCreate.
156 //
157 // If specified, entry_point must be the name of a top-level function from the
158 // same Dart library that contains the app's main() function, and must be
159 // decorated with `@pragma(vm:entry-point)` to ensure the method is not
160 // tree-shaken by the Dart compiler. If conflicting non-null values are passed
161 // to this function and via the FlutterDesktopEngineProperties struct, the run
162 // will fail.
163 //
164 // Returns false if running the engine failed.
165 FLUTTER_EXPORT bool FlutterDesktopEngineRun(FlutterDesktopEngineRef engine,
166 const char* entry_point);
167
168 // DEPRECATED: This is no longer necessary to call, Flutter will take care of
169 // processing engine messages transparently through DispatchMessage.
170 //
171 // Processes any pending events in the Flutter engine, and returns the
172 // number of nanoseconds until the next scheduled event (or max, if none).
173 //
174 // This should be called on every run of the application-level runloop, and
175 // a wait for native events in the runloop should never be longer than the
176 // last return value from this function.
177 FLUTTER_EXPORT uint64_t FlutterDesktopEngineProcessMessages(
178 FlutterDesktopEngineRef engine);
179
180 FLUTTER_EXPORT void FlutterDesktopEngineReloadSystemFonts(
181 FlutterDesktopEngineRef engine);
182
183 // Returns the plugin registrar handle for the plugin with the given name.
184 //
185 // The name must be unique across the application.
186 FLUTTER_EXPORT FlutterDesktopPluginRegistrarRef
187 FlutterDesktopEngineGetPluginRegistrar(FlutterDesktopEngineRef engine,
188 const char* plugin_name);
189
190 // Returns the messenger associated with the engine.
191 //
192 // This does not provide an owning reference, so should *not* be balanced with a
193 // call to |FlutterDesktopMessengerRelease|.
194 //
195 // Callers should use |FlutterDesktopMessengerAddRef| if the returned pointer
196 // will potentially outlive 'engine', such as when passing it to another thread.
197 FLUTTER_EXPORT FlutterDesktopMessengerRef FlutterDesktopEngineGetMessenger(
198 FlutterDesktopEngineRef engine);
199
200 // Returns the texture registrar associated with the engine.
201 FLUTTER_EXPORT FlutterDesktopTextureRegistrarRef
202 FlutterDesktopEngineGetTextureRegistrar(FlutterDesktopEngineRef engine);
203
204 // Schedule a callback to be called after the next frame is drawn.
205 //
206 // This must be called from the platform thread. The callback is executed only
207 // once on the platform thread.
208 FLUTTER_EXPORT void FlutterDesktopEngineSetNextFrameCallback(
209 FlutterDesktopEngineRef engine,
210 VoidCallback callback,
211 void* user_data);
212
213 // ========== View ==========
214
215 // Returns the backing HWND for manipulation in host application.
216 FLUTTER_EXPORT HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view);
217
218 // Returns the DXGI adapter used for rendering or nullptr in case of error.
219 FLUTTER_EXPORT IDXGIAdapter* FlutterDesktopViewGetGraphicsAdapter(
220 FlutterDesktopViewRef view);
221
222 // Called to pass an external window message to the engine for lifecycle
223 // state updates. Non-Flutter windows must call this method in their WndProc
224 // in order to be included in the logic for application lifecycle state
225 // updates. Returns a result if the message should be consumed.
226 FLUTTER_EXPORT bool FlutterDesktopEngineProcessExternalWindowMessage(
227 FlutterDesktopEngineRef engine,
228 HWND hwnd,
229 UINT message,
230 WPARAM wparam,
231 LPARAM lparam,
232 LRESULT* result);
233
234 // ========== Plugin Registrar (extensions) ==========
235 // These are Windows-specific extensions to flutter_plugin_registrar.h
236
237 // Function pointer type for top level WindowProc delegate registration.
238 //
239 // The user data will be whatever was passed to
240 // FlutterDesktopRegisterTopLevelWindowProcHandler.
241 //
242 // Implementations should populate |result| and return true if the WindowProc
243 // was handled and further handling should stop. |result| is ignored if the
244 // function returns false.
245 typedef bool (*FlutterDesktopWindowProcCallback)(HWND /* hwnd */,
246 UINT /* uMsg */,
247 WPARAM /*wParam*/,
248 LPARAM /* lParam*/,
249 void* /* user data */,
250 LRESULT* result);
251
252 // Returns the implicit view associated with this registrar's engine instance,
253 // or null if there is no implicit view.
254 //
255 // See:
256 // https://api.flutter.dev/flutter/dart-ui/PlatformDispatcher/implicitView.html
257 //
258 // DEPRECATED: Use |FlutterDesktopPluginRegistrarGetViewById| instead.
259 FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(
260 FlutterDesktopPluginRegistrarRef registrar);
261
262 // Returns the view associated with the registrar's engine instance, or null if
263 // the view does not exist.
264 FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetViewById(
265 FlutterDesktopPluginRegistrarRef registrar,
266 FlutterDesktopViewId view_id);
267
268 FLUTTER_EXPORT void
269 FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate(
270 FlutterDesktopPluginRegistrarRef registrar,
271 FlutterDesktopWindowProcCallback delegate,
272 void* user_data);
273
274 FLUTTER_EXPORT void
275 FlutterDesktopPluginRegistrarUnregisterTopLevelWindowProcDelegate(
276 FlutterDesktopPluginRegistrarRef registrar,
277 FlutterDesktopWindowProcCallback delegate);
278
279 // ========== Freestanding Utilities ==========
280
281 // Gets the DPI for a given |hwnd|, depending on the supported APIs per
282 // windows version and DPI awareness mode. If nullptr is passed, returns the DPI
283 // of the primary monitor.
284 //
285 // This uses the same logic and fallback for older Windows versions that is used
286 // internally by Flutter to determine the DPI to use for displaying Flutter
287 // content, so should be used by any code (e.g., in plugins) that translates
288 // between Windows and Dart sizes/offsets.
289 FLUTTER_EXPORT UINT FlutterDesktopGetDpiForHWND(HWND hwnd);
290
291 // Gets the DPI for a given |monitor|. If the API is not available, a default
292 // DPI of 96 is returned.
293 //
294 // See FlutterDesktopGetDpiForHWND for more information.
295 FLUTTER_EXPORT UINT FlutterDesktopGetDpiForMonitor(HMONITOR monitor);
296
297 // Reopens stdout and stderr and resysncs the standard library output streams.
298 // Should be called if output is being directed somewhere in the runner process
299 // (e.g., after an AllocConsole call).
300 FLUTTER_EXPORT void FlutterDesktopResyncOutputStreams();
301
302 #if defined(__cplusplus)
303 } // extern "C"
304 #endif
305
306 #endif // FLUTTER_SHELL_PLATFORM_WINDOWS_PUBLIC_FLUTTER_WINDOWS_H_
flutter_export.h
FLUTTER_EXPORT
#define FLUTTER_EXPORT
Definition: flutter_export.h:23
flutter_messenger.h
FlutterDesktopMessengerRef
struct FlutterDesktopMessenger * FlutterDesktopMessengerRef
Definition: flutter_messenger.h:19
flutter_plugin_registrar.h
FlutterDesktopTextureRegistrarRef
struct FlutterDesktopTextureRegistrar * FlutterDesktopTextureRegistrarRef
Definition: flutter_texture_registrar.h:19
FlutterDesktopResyncOutputStreams
FLUTTER_EXPORT void FlutterDesktopResyncOutputStreams()
Definition: flutter_windows.cc:324
FlutterDesktopViewControllerGetView
FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopViewControllerGetView(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:153
FlutterDesktopEngineGetTextureRegistrar
FLUTTER_EXPORT FlutterDesktopTextureRegistrarRef FlutterDesktopEngineGetTextureRegistrar(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:233
FlutterDesktopViewControllerRef
struct FlutterDesktopViewController * FlutterDesktopViewControllerRef
Definition: flutter_windows.h:25
FlutterDesktopViewControllerDestroy
FLUTTER_EXPORT void FlutterDesktopViewControllerDestroy(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:135
FlutterDesktopWindowProcCallback
bool(* FlutterDesktopWindowProcCallback)(HWND, UINT, WPARAM, LPARAM, void *, LRESULT *result)
Definition: flutter_windows.h:245
FlutterDesktopEngineRef
struct FlutterDesktopEngine * FlutterDesktopEngineRef
Definition: flutter_windows.h:33
FlutterDesktopEngineRun
FLUTTER_EXPORT bool FlutterDesktopEngineRun(FlutterDesktopEngineRef engine, const char *entry_point)
Definition: flutter_windows.cc:200
FlutterDesktopEngineProcessExternalWindowMessage
FLUTTER_EXPORT bool FlutterDesktopEngineProcessExternalWindowMessage(FlutterDesktopEngineRef engine, HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam, LRESULT *result)
Definition: flutter_windows.cc:266
FlutterDesktopViewId
int64_t FlutterDesktopViewId
Definition: flutter_windows.h:36
FlutterDesktopViewGetHWND
FLUTTER_EXPORT HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view)
Definition: flutter_windows.cc:246
FlutterDesktopViewControllerForceRedraw
FLUTTER_EXPORT void FlutterDesktopViewControllerForceRedraw(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:159
FlutterDesktopEngineGetMessenger
FLUTTER_EXPORT FlutterDesktopMessengerRef FlutterDesktopEngineGetMessenger(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:228
FlutterDesktopViewRef
struct FlutterDesktopView * FlutterDesktopViewRef
Definition: flutter_windows.h:29
FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate
FLUTTER_EXPORT void FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate(FlutterDesktopPluginRegistrarRef registrar, FlutterDesktopWindowProcCallback delegate, void *user_data)
Definition: flutter_windows.cc:301
FlutterDesktopViewGetGraphicsAdapter
FLUTTER_EXPORT IDXGIAdapter * FlutterDesktopViewGetGraphicsAdapter(FlutterDesktopViewRef view)
Definition: flutter_windows.cc:250
VoidCallback
void(* VoidCallback)(void *)
Definition: flutter_windows.h:21
FlutterDesktopPluginRegistrarGetViewById
FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetViewById(FlutterDesktopPluginRegistrarRef registrar, FlutterDesktopViewId view_id)
Definition: flutter_windows.cc:295
FlutterDesktopEngineDestroy
FLUTTER_EXPORT bool FlutterDesktopEngineDestroy(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:190
FlutterDesktopViewControllerGetEngine
FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopViewControllerGetEngine(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:147
FlutterDesktopGetDpiForHWND
FLUTTER_EXPORT UINT FlutterDesktopGetDpiForHWND(HWND hwnd)
Definition: flutter_windows.cc:316
FlutterDesktopEngineGetPluginRegistrar
FLUTTER_EXPORT FlutterDesktopPluginRegistrarRef FlutterDesktopEngineGetPluginRegistrar(FlutterDesktopEngineRef engine, const char *plugin_name)
Definition: flutter_windows.cc:218
FlutterDesktopPluginRegistrarUnregisterTopLevelWindowProcDelegate
FLUTTER_EXPORT void FlutterDesktopPluginRegistrarUnregisterTopLevelWindowProcDelegate(FlutterDesktopPluginRegistrarRef registrar, FlutterDesktopWindowProcCallback delegate)
Definition: flutter_windows.cc:309
FlutterDesktopGetDpiForMonitor
FLUTTER_EXPORT UINT FlutterDesktopGetDpiForMonitor(HMONITOR monitor)
Definition: flutter_windows.cc:320
FlutterDesktopEngineReloadSystemFonts
FLUTTER_EXPORT void FlutterDesktopEngineReloadSystemFonts(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:214
FlutterDesktopViewControllerGetViewId
FLUTTER_EXPORT FlutterDesktopViewId FlutterDesktopViewControllerGetViewId(FlutterDesktopViewControllerRef view_controller)
Definition: flutter_windows.cc:141
FlutterDesktopEngineCreate
FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopEngineCreate(const FlutterDesktopEngineProperties *engine_properties)
Definition: flutter_windows.cc:183
FlutterDesktopViewControllerCreate
FLUTTER_EXPORT FlutterDesktopViewControllerRef FlutterDesktopViewControllerCreate(int width, int height, FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:121
FlutterDesktopViewControllerHandleTopLevelWindowProc
FLUTTER_EXPORT bool FlutterDesktopViewControllerHandleTopLevelWindowProc(FlutterDesktopViewControllerRef controller, HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam, LRESULT *result)
Definition: flutter_windows.cc:165
FlutterDesktopEngineSetNextFrameCallback
FLUTTER_EXPORT void FlutterDesktopEngineSetNextFrameCallback(FlutterDesktopEngineRef engine, VoidCallback callback, void *user_data)
Definition: flutter_windows.cc:239
FlutterDesktopEngineProcessMessages
FLUTTER_EXPORT uint64_t FlutterDesktopEngineProcessMessages(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:210
FlutterDesktopPluginRegistrarGetView
FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(FlutterDesktopPluginRegistrarRef registrar)
Definition: flutter_windows.cc:290
user_data
void * user_data
Definition: flutter_windows_view_unittests.cc:53
callback
FlutterDesktopBinaryReply callback
Definition: flutter_windows_view_unittests.cc:52
message
Win32Message message
Definition: keyboard_unittests.cc:137
FlutterDesktopEngineProperties
Definition: flutter_windows.h:39
FlutterDesktopEngineProperties::dart_entrypoint
const char * dart_entrypoint
Definition: flutter_windows.h:62
FlutterDesktopEngineProperties::icu_data_path
const wchar_t * icu_data_path
Definition: flutter_windows.h:48
FlutterDesktopEngineProperties::dart_entrypoint_argc
int dart_entrypoint_argc
Definition: flutter_windows.h:65
FlutterDesktopEngineProperties::assets_path
const wchar_t * assets_path
Definition: flutter_windows.h:43
FlutterDesktopEngineProperties::dart_entrypoint_argv
const char ** dart_entrypoint_argv
Definition: flutter_windows.h:69
FlutterDesktopEngineProperties::aot_library_path
const wchar_t * aot_library_path
Definition: flutter_windows.h:54
FlutterDesktopPluginRegistrar
Definition: window_state.h:23