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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 // Configures how the Flutter engine selects a GPU.
39 typedef enum {
40 // No preference.
41 NoPreference,
42 // Prefer energy efficiency over performance, such as an integrated GPU.
43 // This falls back to a high performance GPU if no low power GPU is
44 // available.
45 LowPowerPreference,
46 } FlutterDesktopGpuPreference;
47
48 // Configures the thread policy for running the UI isolate.
49 typedef enum {
50 // Default value. Currently will run the UI isolate on separate thread,
51 // later will be changed to running the UI isolate on platform thread.
52 Default,
53 // Run the UI isolate on platform thread.
54 RunOnPlatformThread,
55 // Run the UI isolate on a separate thread.
56 RunOnSeparateThread,
57 } FlutterDesktopUIThreadPolicy;
58
59 // Properties for configuring a Flutter engine instance.
60 typedef struct {
61 // The path to the flutter_assets folder for the application to be run.
62 // This can either be an absolute path or a path relative to the directory
63 // containing the executable.
64 const wchar_t* assets_path;
65
66 // The path to the icudtl.dat file for the version of Flutter you are using.
67 // This can either be an absolute path or a path relative to the directory
68 // containing the executable.
69 const wchar_t* icu_data_path;
70
71 // The path to the AOT library file for your application, if any.
72 // This can either be an absolute path or a path relative to the directory
73 // containing the executable. This can be nullptr for a non-AOT build, as
74 // it will be ignored in that case.
75 const wchar_t* aot_library_path;
76
77 // The name of the top-level Dart entrypoint function. If null or the empty
78 // string, 'main' is assumed. If a custom entrypoint is used, this parameter
79 // must specifiy the name of a top-level function in the same Dart library as
80 // the app's main() function. Custom entrypoint functions must be decorated
81 // with `@pragma('vm:entry-point')` to ensure the method is not tree-shaken
82 // by the Dart compiler.
83 const char* dart_entrypoint;
84
85 // Number of elements in the array passed in as dart_entrypoint_argv.
86 int dart_entrypoint_argc;
87
88 // Array of Dart entrypoint arguments. This is deep copied during the call
89 // to FlutterDesktopEngineCreate.
90 const char** dart_entrypoint_argv;
91
92 // GPU choice preference
93 FlutterDesktopGpuPreference gpu_preference;
94
95 // Policy for the thread that runs UI isolate.
96 FlutterDesktopUIThreadPolicy ui_thread_policy;
97 } FlutterDesktopEngineProperties;
98
99 // ========== View Controller ==========
100
101 // Creates a view that hosts and displays the given engine instance.
102 //
103 // This takes ownership of |engine|, so FlutterDesktopEngineDestroy should no
104 // longer be called on it, as it will be called internally when the view
105 // controller is destroyed. If creating the view controller fails, the engine
106 // will be destroyed immediately.
107 //
108 // If |engine| is not already running, the view controller will start running
109 // it automatically before displaying the window.
110 //
111 // The caller owns the returned reference, and is responsible for calling
112 // FlutterDesktopViewControllerDestroy. Returns a null pointer in the event of
113 // an error.
114 //
115 // The Win32 implementation accepts width, height with view hookup explicitly
116 // performed using the caller using HWND parenting.
117 FLUTTER_EXPORT FlutterDesktopViewControllerRef
118 FlutterDesktopViewControllerCreate(int width,
119 int height,
120 FlutterDesktopEngineRef engine);
121
122 // Shuts down the engine instance associated with |controller|, and cleans up
123 // associated state.
124 //
125 // |controller| is no longer valid after this call.
126 FLUTTER_EXPORT void FlutterDesktopViewControllerDestroy(
127 FlutterDesktopViewControllerRef controller);
128
129 // Returns the view controller's view ID.
130 FLUTTER_EXPORT FlutterDesktopViewId FlutterDesktopViewControllerGetViewId(
131 FlutterDesktopViewControllerRef view_controller);
132
133 // Returns the handle for the engine running in FlutterDesktopViewControllerRef.
134 //
135 // Its lifetime is the same as the |controller|'s.
136 FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopViewControllerGetEngine(
137 FlutterDesktopViewControllerRef controller);
138
139 // Returns the view managed by the given controller.
140 FLUTTER_EXPORT FlutterDesktopViewRef
141 FlutterDesktopViewControllerGetView(FlutterDesktopViewControllerRef controller);
142
143 // Requests new frame from the engine and repaints the view.
144 FLUTTER_EXPORT void FlutterDesktopViewControllerForceRedraw(
145 FlutterDesktopViewControllerRef controller);
146
147 // Allows the Flutter engine and any interested plugins an opportunity to
148 // handle the given message.
149 //
150 // If the WindowProc was handled and further handling should stop, this returns
151 // true and |result| will be populated. |result| is not set if returning false.
152 FLUTTER_EXPORT bool FlutterDesktopViewControllerHandleTopLevelWindowProc(
153 FlutterDesktopViewControllerRef controller,
154 HWND hwnd,
155 UINT message,
156 WPARAM wparam,
157 LPARAM lparam,
158 LRESULT* result);
159
160 // ========== Engine ==========
161
162 // Creates a Flutter engine with the given properties.
163 //
164 // The caller owns the returned reference, and is responsible for calling
165 // FlutterDesktopEngineDestroy. The lifetime of |engine_properties| is required
166 // to extend only until the end of this call.
167 FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopEngineCreate(
168 const FlutterDesktopEngineProperties* engine_properties);
169
170 // Shuts down and destroys the given engine instance. Returns true if the
171 // shutdown was successful, or if the engine was not running.
172 //
173 // |engine| is no longer valid after this call.
174 FLUTTER_EXPORT bool FlutterDesktopEngineDestroy(FlutterDesktopEngineRef engine);
175
176 // Starts running the given engine instance.
177 //
178 // The entry_point parameter is deprecated but preserved for
179 // backward-compatibility. If desired, a custom Dart entrypoint function can be
180 // set in the dart_entrypoint field of the FlutterDesktopEngineProperties
181 // struct passed to FlutterDesktopEngineCreate.
182 //
183 // If specified, entry_point must be the name of a top-level function from the
184 // same Dart library that contains the app's main() function, and must be
185 // decorated with `@pragma(vm:entry-point)` to ensure the method is not
186 // tree-shaken by the Dart compiler. If conflicting non-null values are passed
187 // to this function and via the FlutterDesktopEngineProperties struct, the run
188 // will fail.
189 //
190 // Returns false if running the engine failed.
191 FLUTTER_EXPORT bool FlutterDesktopEngineRun(FlutterDesktopEngineRef engine,
192 const char* entry_point);
193
194 // DEPRECATED: This is no longer necessary to call, Flutter will take care of
195 // processing engine messages transparently through DispatchMessage.
196 //
197 // Processes any pending events in the Flutter engine, and returns the
198 // number of nanoseconds until the next scheduled event (or max, if none).
199 //
200 // This should be called on every run of the application-level runloop, and
201 // a wait for native events in the runloop should never be longer than the
202 // last return value from this function.
203 FLUTTER_EXPORT uint64_t
204 FlutterDesktopEngineProcessMessages(FlutterDesktopEngineRef engine);
205
206 FLUTTER_EXPORT void FlutterDesktopEngineReloadSystemFonts(
207 FlutterDesktopEngineRef engine);
208
209 // Returns the plugin registrar handle for the plugin with the given name.
210 //
211 // The name must be unique across the application.
212 FLUTTER_EXPORT FlutterDesktopPluginRegistrarRef
213 FlutterDesktopEngineGetPluginRegistrar(FlutterDesktopEngineRef engine,
214 const char* plugin_name);
215
216 // Returns the messenger associated with the engine.
217 //
218 // This does not provide an owning reference, so should *not* be balanced with a
219 // call to |FlutterDesktopMessengerRelease|.
220 //
221 // Callers should use |FlutterDesktopMessengerAddRef| if the returned pointer
222 // will potentially outlive 'engine', such as when passing it to another thread.
223 FLUTTER_EXPORT FlutterDesktopMessengerRef
224 FlutterDesktopEngineGetMessenger(FlutterDesktopEngineRef engine);
225
226 // Returns the texture registrar associated with the engine.
227 FLUTTER_EXPORT FlutterDesktopTextureRegistrarRef
228 FlutterDesktopEngineGetTextureRegistrar(FlutterDesktopEngineRef engine);
229
230 // Schedule a callback to be called after the next frame is drawn.
231 //
232 // This must be called from the platform thread. The callback is executed only
233 // once on the platform thread.
234 FLUTTER_EXPORT void FlutterDesktopEngineSetNextFrameCallback(
235 FlutterDesktopEngineRef engine,
236 VoidCallback callback,
237 void* user_data);
238
239 // ========== View ==========
240
241 // Returns the backing HWND for manipulation in host application.
242 FLUTTER_EXPORT HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view);
243
244 // Returns the DXGI adapter used for rendering or nullptr in case of error.
245 FLUTTER_EXPORT IDXGIAdapter* FlutterDesktopViewGetGraphicsAdapter(
246 FlutterDesktopViewRef view);
247
248 // Called to pass an external window message to the engine for lifecycle
249 // state updates. Non-Flutter windows must call this method in their WndProc
250 // in order to be included in the logic for application lifecycle state
251 // updates. Returns a result if the message should be consumed.
252 FLUTTER_EXPORT bool FlutterDesktopEngineProcessExternalWindowMessage(
253 FlutterDesktopEngineRef engine,
254 HWND hwnd,
255 UINT message,
256 WPARAM wparam,
257 LPARAM lparam,
258 LRESULT* result);
259
260 // ========== Plugin Registrar (extensions) ==========
261 // These are Windows-specific extensions to flutter_plugin_registrar.h
262
263 // Function pointer type for top level WindowProc delegate registration.
264 //
265 // The user data will be whatever was passed to
266 // FlutterDesktopRegisterTopLevelWindowProcHandler.
267 //
268 // Implementations should populate |result| and return true if the WindowProc
269 // was handled and further handling should stop. |result| is ignored if the
270 // function returns false.
271 typedef bool (*FlutterDesktopWindowProcCallback)(HWND /* hwnd */,
272 UINT /* uMsg */,
273 WPARAM /*wParam*/,
274 LPARAM /* lParam*/,
275 void* /* user data */,
276 LRESULT* result);
277
278 // Returns the implicit view associated with this registrar's engine instance,
279 // or null if there is no implicit view.
280 //
281 // See:
282 // https://api.flutter.dev/flutter/dart-ui/PlatformDispatcher/implicitView.html
283 //
284 // DEPRECATED: Use |FlutterDesktopPluginRegistrarGetViewById| instead.
285 FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(
286 FlutterDesktopPluginRegistrarRef registrar);
287
288 // Returns the view associated with the registrar's engine instance, or null if
289 // the view does not exist.
290 FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetViewById(
291 FlutterDesktopPluginRegistrarRef registrar,
292 FlutterDesktopViewId view_id);
293
294 FLUTTER_EXPORT void
295 FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate(
296 FlutterDesktopPluginRegistrarRef registrar,
297 FlutterDesktopWindowProcCallback delegate,
298 void* user_data);
299
300 FLUTTER_EXPORT void
301 FlutterDesktopPluginRegistrarUnregisterTopLevelWindowProcDelegate(
302 FlutterDesktopPluginRegistrarRef registrar,
303 FlutterDesktopWindowProcCallback delegate);
304
305 // ========== Freestanding Utilities ==========
306
307 // Gets the DPI for a given |hwnd|, depending on the supported APIs per
308 // windows version and DPI awareness mode. If nullptr is passed, returns the DPI
309 // of the primary monitor.
310 //
311 // This uses the same logic and fallback for older Windows versions that is used
312 // internally by Flutter to determine the DPI to use for displaying Flutter
313 // content, so should be used by any code (e.g., in plugins) that translates
314 // between Windows and Dart sizes/offsets.
315 FLUTTER_EXPORT UINT FlutterDesktopGetDpiForHWND(HWND hwnd);
316
317 // Gets the DPI for a given |monitor|. If the API is not available, a default
318 // DPI of 96 is returned.
319 //
320 // See FlutterDesktopGetDpiForHWND for more information.
321 FLUTTER_EXPORT UINT FlutterDesktopGetDpiForMonitor(HMONITOR monitor);
322
323 // Reopens stdout and stderr and resysncs the standard library output streams.
324 // Should be called if output is being directed somewhere in the runner process
325 // (e.g., after an AllocConsole call).
326 FLUTTER_EXPORT void FlutterDesktopResyncOutputStreams();
327
328 #if defined(__cplusplus)
329 } // extern "C"
330 #endif
331
332 #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:331
FlutterDesktopViewControllerGetView
FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopViewControllerGetView(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:154
FlutterDesktopEngineGetTextureRegistrar
FLUTTER_EXPORT FlutterDesktopTextureRegistrarRef FlutterDesktopEngineGetTextureRegistrar(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:240
FlutterDesktopViewControllerRef
struct FlutterDesktopViewController * FlutterDesktopViewControllerRef
Definition: flutter_windows.h:25
FlutterDesktopViewControllerDestroy
FLUTTER_EXPORT void FlutterDesktopViewControllerDestroy(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:136
FlutterDesktopWindowProcCallback
bool(* FlutterDesktopWindowProcCallback)(HWND, UINT, WPARAM, LPARAM, void *, LRESULT *result)
Definition: flutter_windows.h:271
FlutterDesktopEngineRef
struct FlutterDesktopEngine * FlutterDesktopEngineRef
Definition: flutter_windows.h:33
FlutterDesktopEngineRun
FLUTTER_EXPORT bool FlutterDesktopEngineRun(FlutterDesktopEngineRef engine, const char *entry_point)
Definition: flutter_windows.cc:207
FlutterDesktopUIThreadPolicy
FlutterDesktopUIThreadPolicy
Definition: flutter_windows.h:49
RunOnPlatformThread
@ RunOnPlatformThread
Definition: flutter_windows.h:54
RunOnSeparateThread
@ RunOnSeparateThread
Definition: flutter_windows.h:56
Default
@ Default
Definition: flutter_windows.h:52
FlutterDesktopEngineProcessExternalWindowMessage
FLUTTER_EXPORT bool FlutterDesktopEngineProcessExternalWindowMessage(FlutterDesktopEngineRef engine, HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam, LRESULT *result)
Definition: flutter_windows.cc:273
FlutterDesktopViewId
int64_t FlutterDesktopViewId
Definition: flutter_windows.h:36
FlutterDesktopViewGetHWND
FLUTTER_EXPORT HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view)
Definition: flutter_windows.cc:253
FlutterDesktopViewControllerForceRedraw
FLUTTER_EXPORT void FlutterDesktopViewControllerForceRedraw(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:160
FlutterDesktopEngineGetMessenger
FLUTTER_EXPORT FlutterDesktopMessengerRef FlutterDesktopEngineGetMessenger(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:235
FlutterDesktopViewRef
struct FlutterDesktopView * FlutterDesktopViewRef
Definition: flutter_windows.h:29
FlutterDesktopGpuPreference
FlutterDesktopGpuPreference
Definition: flutter_windows.h:39
LowPowerPreference
@ LowPowerPreference
Definition: flutter_windows.h:45
NoPreference
@ NoPreference
Definition: flutter_windows.h:41
FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate
FLUTTER_EXPORT void FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate(FlutterDesktopPluginRegistrarRef registrar, FlutterDesktopWindowProcCallback delegate, void *user_data)
Definition: flutter_windows.cc:308
FlutterDesktopViewGetGraphicsAdapter
FLUTTER_EXPORT IDXGIAdapter * FlutterDesktopViewGetGraphicsAdapter(FlutterDesktopViewRef view)
Definition: flutter_windows.cc:257
VoidCallback
void(* VoidCallback)(void *)
Definition: flutter_windows.h:21
FlutterDesktopPluginRegistrarGetViewById
FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetViewById(FlutterDesktopPluginRegistrarRef registrar, FlutterDesktopViewId view_id)
Definition: flutter_windows.cc:302
FlutterDesktopEngineDestroy
FLUTTER_EXPORT bool FlutterDesktopEngineDestroy(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:191
FlutterDesktopViewControllerGetEngine
FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopViewControllerGetEngine(FlutterDesktopViewControllerRef controller)
Definition: flutter_windows.cc:148
FlutterDesktopGetDpiForHWND
FLUTTER_EXPORT UINT FlutterDesktopGetDpiForHWND(HWND hwnd)
Definition: flutter_windows.cc:323
FlutterDesktopEngineGetPluginRegistrar
FLUTTER_EXPORT FlutterDesktopPluginRegistrarRef FlutterDesktopEngineGetPluginRegistrar(FlutterDesktopEngineRef engine, const char *plugin_name)
Definition: flutter_windows.cc:225
FlutterDesktopPluginRegistrarUnregisterTopLevelWindowProcDelegate
FLUTTER_EXPORT void FlutterDesktopPluginRegistrarUnregisterTopLevelWindowProcDelegate(FlutterDesktopPluginRegistrarRef registrar, FlutterDesktopWindowProcCallback delegate)
Definition: flutter_windows.cc:316
FlutterDesktopGetDpiForMonitor
FLUTTER_EXPORT UINT FlutterDesktopGetDpiForMonitor(HMONITOR monitor)
Definition: flutter_windows.cc:327
FlutterDesktopEngineReloadSystemFonts
FLUTTER_EXPORT void FlutterDesktopEngineReloadSystemFonts(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:221
FlutterDesktopViewControllerGetViewId
FLUTTER_EXPORT FlutterDesktopViewId FlutterDesktopViewControllerGetViewId(FlutterDesktopViewControllerRef view_controller)
Definition: flutter_windows.cc:142
FlutterDesktopEngineCreate
FLUTTER_EXPORT FlutterDesktopEngineRef FlutterDesktopEngineCreate(const FlutterDesktopEngineProperties *engine_properties)
Definition: flutter_windows.cc:184
FlutterDesktopViewControllerCreate
FLUTTER_EXPORT FlutterDesktopViewControllerRef FlutterDesktopViewControllerCreate(int width, int height, FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:122
FlutterDesktopViewControllerHandleTopLevelWindowProc
FLUTTER_EXPORT bool FlutterDesktopViewControllerHandleTopLevelWindowProc(FlutterDesktopViewControllerRef controller, HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam, LRESULT *result)
Definition: flutter_windows.cc:166
FlutterDesktopEngineSetNextFrameCallback
FLUTTER_EXPORT void FlutterDesktopEngineSetNextFrameCallback(FlutterDesktopEngineRef engine, VoidCallback callback, void *user_data)
Definition: flutter_windows.cc:246
FlutterDesktopEngineProcessMessages
FLUTTER_EXPORT uint64_t FlutterDesktopEngineProcessMessages(FlutterDesktopEngineRef engine)
Definition: flutter_windows.cc:217
FlutterDesktopPluginRegistrarGetView
FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(FlutterDesktopPluginRegistrarRef registrar)
Definition: flutter_windows.cc:297
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:60
FlutterDesktopEngineProperties::dart_entrypoint
const char * dart_entrypoint
Definition: flutter_windows.h:83
FlutterDesktopEngineProperties::icu_data_path
const wchar_t * icu_data_path
Definition: flutter_windows.h:69
FlutterDesktopEngineProperties::dart_entrypoint_argc
int dart_entrypoint_argc
Definition: flutter_windows.h:86
FlutterDesktopEngineProperties::assets_path
const wchar_t * assets_path
Definition: flutter_windows.h:64
FlutterDesktopEngineProperties::dart_entrypoint_argv
const char ** dart_entrypoint_argv
Definition: flutter_windows.h:90
FlutterDesktopEngineProperties::ui_thread_policy
FlutterDesktopUIThreadPolicy ui_thread_policy
Definition: flutter_windows.h:96
FlutterDesktopEngineProperties::aot_library_path
const wchar_t * aot_library_path
Definition: flutter_windows.h:75
FlutterDesktopEngineProperties::gpu_preference
FlutterDesktopGpuPreference gpu_preference
Definition: flutter_windows.h:93
FlutterDesktopPluginRegistrar
Definition: window_state.h:23