| Flutter iOS Embedder |

Macros | Functions | Variables
FlutterDartProject.mm File Reference
`#import "flutter/shell/platform/darwin/ios/framework/Source/FlutterDartProject_Internal.h"`
`#import <Metal/Metal.h>`
`#import <UIKit/UIKit.h>`
`#include <syslog.h>`
`#include "flutter/common/constants.h"`
`#include "flutter/shell/common/switches.h"`
`#import "flutter/shell/platform/darwin/common/command_line.h"`

Go to the source code of this file.

## Macros
#define | FML_USED_ON_EMBEDDER

## Functions
static BOOL | DoesHardwareSupportWideGamut ()
flutter::Settings | FLTDefaultSettingsForBundle (NSBundle *bundle, NSProcessInfo *processInfoOrNil)

## Variables
const FLUTTER_ASSERT_ARC uint8_t | kPlatformStrongDill []
const intptr_t | kPlatformStrongDillSize
static const char * | kApplicationKernelSnapshotFileName = "kernel_blob.bin"

## Macro Definition Documentation

## ◆ FML_USED_ON_EMBEDDER

#define FML_USED_ON_EMBEDDER

Definition at line 5 of file FlutterDartProject.mm.

## Function Documentation

## ◆ DoesHardwareSupportWideGamut()

static BOOL DoesHardwareSupportWideGamut | ( |  | ) |
| static

Definition at line 30 of file FlutterDartProject.mm.

30 {
31 static BOOL result = NO;
32 static dispatch_once_t once_token = 0;
33 dispatch_once(&once_token, ^{
34 id<MTLDevice> device = MTLCreateSystemDefaultDevice();
35 if (@available(iOS 13.0, *)) {
36 // MTLGPUFamilyApple2 = A9/A10
37 result = [device supportsFamily:MTLGPUFamilyApple2];
38 } else {
39 // A9/A10 on iOS 10+
40 result = [device supportsFeatureSet:MTLFeatureSet_iOS_GPUFamily3_v2];
41 }
42 });
43 return result;
44 }

Referenced by FLTDefaultSettingsForBundle().

## ◆ FLTDefaultSettingsForBundle()

flutter::Settings FLTDefaultSettingsForBundle | ( | NSBundle * | bundle,
|  | NSProcessInfo * | processInfoOrNil
| ) |  |

Definition at line 46 of file FlutterDartProject.mm.

46 {
47 auto command_line = flutter::CommandLineFromNSProcessInfo(processInfoOrNil);
48
49 // Precedence:
50 // 1. Settings from the specified NSBundle (except for enable-impeller).
51 // 2. Settings passed explicitly via command-line arguments.
52 // 3. Settings from the NSBundle with the default bundle ID.
53 // 4. Settings from the main NSBundle and default values.
54
55 NSBundle* mainBundle = FLTGetApplicationBundle();
56 NSBundle* engineBundle = [NSBundle bundleForClass:[FlutterDartProject class]];
57
58 bool hasExplicitBundle = bundle != nil;
59 if (bundle == nil) {
60 bundle = FLTFrameworkBundleWithIdentifier([FlutterDartProject defaultBundleIdentifier]);
61 }
62
63 auto settings = flutter::SettingsFromCommandLine(command_line);
64
65 settings.task_observer_add = [](intptr_t key, const fml::closure& callback) {
66 fml::MessageLoop::GetCurrent().AddTaskObserver(key, callback);
67 };
68
69 settings.task_observer_remove = [](intptr_t key) {
70 fml::MessageLoop::GetCurrent().RemoveTaskObserver(key);
71 };
72
73 settings.log_message_callback = [](const std::string& tag, const std::string& message) {
74 // TODO(cbracken): replace this with os_log-based approach.
75 // https://github.com/flutter/flutter/issues/44030
76 std::stringstream stream;
77 if (!tag.empty()) {
78 stream << tag << ": ";
79 }
80 stream << message;
81 std::string log = stream.str();
82 syslog(LOG_ALERT, "%.*s", (int)log.size(), log.c_str());
83 };
84
85 settings.enable_platform_isolates = true;
86
87 // The command line arguments may not always be complete. If they aren't, attempt to fill in
88 // defaults.
89
90 // Flutter ships the ICU data file in the bundle of the engine. Look for it there.
91 if (settings.icu_data_path.empty()) {
92 NSString* icuDataPath = [engineBundle pathForResource:@"icudtl" ofType:@"dat"];
93 if (icuDataPath.length > 0) {
94 settings.icu_data_path = icuDataPath.UTF8String;
95 }
96 }
97
98 if (flutter::DartVM::IsRunningPrecompiledCode()) {
99 if (hasExplicitBundle) {
100 NSString* executablePath = bundle.executablePath;
101 if ([[NSFileManager defaultManager] fileExistsAtPath:executablePath]) {
102 settings.application_library_path.push_back(executablePath.UTF8String);
103 }
104 }
105
106 // No application bundle specified. Try a known location from the main bundle's Info.plist.
107 if (settings.application_library_path.empty()) {
108 NSString* libraryName = [mainBundle objectForInfoDictionaryKey:@"FLTLibraryPath"];
109 NSString* libraryPath = [mainBundle pathForResource:libraryName ofType:@""];
110 if (libraryPath.length > 0) {
111 NSString* executablePath = [NSBundle bundleWithPath:libraryPath].executablePath;
112 if (executablePath.length > 0) {
113 settings.application_library_path.push_back(executablePath.UTF8String);
114 }
115 }
116 }
117
118 // In case the application bundle is still not specified, look for the App.framework in the
119 // Frameworks directory.
120 if (settings.application_library_path.empty()) {
121 NSString* applicationFrameworkPath = [mainBundle pathForResource:@"Frameworks/App.framework"
122 ofType:@""];
123 if (applicationFrameworkPath.length > 0) {
124 NSString* executablePath =
125 [NSBundle bundleWithPath:applicationFrameworkPath].executablePath;
126 if (executablePath.length > 0) {
127 settings.application_library_path.push_back(executablePath.UTF8String);
128 }
129 }
130 }
131 }
132
133 // Checks to see if the flutter assets directory is already present.
134 if (settings.assets_path.empty()) {
135 NSString* assetsPath = FLTAssetsPathFromBundle(bundle);
136
137 if (assetsPath.length == 0) {
138 NSLog(@"Failed to find assets path for \"%@\"", bundle);
139 } else {
140 settings.assets_path = assetsPath.UTF8String;
141
142 // Check if there is an application kernel snapshot in the assets directory we could
143 // potentially use. Looking for the snapshot makes sense only if we have a VM that can use
144 // it.
145 if (!flutter::DartVM::IsRunningPrecompiledCode()) {
146 NSURL* applicationKernelSnapshotURL =
147 [NSURL URLWithString:@(kApplicationKernelSnapshotFileName)
148 relativeToURL:[NSURL fileURLWithPath:assetsPath]];
149 NSError* error;
150 if ([applicationKernelSnapshotURL checkResourceIsReachableAndReturnError:&error]) {
151 settings.application_kernel_asset = applicationKernelSnapshotURL.path.UTF8String;
152 } else {
153 NSLog(@"Failed to find snapshot at %@: %@", applicationKernelSnapshotURL.path, error);
154 }
155 }
156 }
157 }
158
159 // Domain network configuration
160 // Disabled in https://github.com/flutter/flutter/issues/72723.
161 // Re-enable in https://github.com/flutter/flutter/issues/54448.
162 settings.may_insecurely_connect_to_all_domains = true;
163 settings.domain_network_policy = "";
164
165 // Whether to enable wide gamut colors.
166 #if TARGET_OS_SIMULATOR
167 // As of Xcode 14.1, the wide gamut surface pixel formats are not supported by
168 // the simulator.
169 settings.enable_wide_gamut = false;
170 // Removes unused function warning.
171 (void)DoesHardwareSupportWideGamut;
172 #else
173 NSNumber* nsEnableWideGamut = [mainBundle objectForInfoDictionaryKey:@"FLTEnableWideGamut"];
174 BOOL enableWideGamut =
175 (nsEnableWideGamut ? nsEnableWideGamut.boolValue : YES) && DoesHardwareSupportWideGamut();
176 settings.enable_wide_gamut = enableWideGamut;
177 #endif
178
179 // TODO(dnfield): We should reverse the order for all these settings so that command line options
180 // are preferred to plist settings. https://github.com/flutter/flutter/issues/124049
181 // Whether to enable Impeller. If the command line explicitly
182 // specified an option for this, ignore what's in the plist.
183 if (!command_line.HasOption("enable-impeller")) {
184 // Next, look in the app bundle.
185 NSNumber* enableImpeller = [bundle objectForInfoDictionaryKey:@"FLTEnableImpeller"];
186 if (enableImpeller == nil) {
187 // If it isn't in the app bundle, look in the main bundle.
188 enableImpeller = [mainBundle objectForInfoDictionaryKey:@"FLTEnableImpeller"];
189 }
190 // Change the default only if the option is present.
191 if (enableImpeller != nil) {
192 settings.enable_impeller = enableImpeller.boolValue;
193 }
194 }
195
196 settings.warn_on_impeller_opt_out = true;
197
198 NSNumber* enableTraceSystrace = [mainBundle objectForInfoDictionaryKey:@"FLTTraceSystrace"];
199 // Change the default only if the option is present.
200 if (enableTraceSystrace != nil) {
201 settings.trace_systrace = enableTraceSystrace.boolValue;
202 }
203
204 NSNumber* enableDartAsserts = [mainBundle objectForInfoDictionaryKey:@"FLTEnableDartAsserts"];
205 if (enableDartAsserts != nil) {
206 settings.dart_flags.push_back("--enable-asserts");
207 }
208
209 NSNumber* enableDartProfiling = [mainBundle objectForInfoDictionaryKey:@"FLTEnableDartProfiling"];
210 // Change the default only if the option is present.
211 if (enableDartProfiling != nil) {
212 settings.enable_dart_profiling = enableDartProfiling.boolValue;
213 }
214
215 // Leak Dart VM settings, set whether leave or clean up the VM after the last shell shuts down.
216 NSNumber* leakDartVM = [mainBundle objectForInfoDictionaryKey:@"FLTLeakDartVM"];
217 // It will change the default leak_vm value in settings only if the key exists.
218 if (leakDartVM != nil) {
219 settings.leak_vm = leakDartVM.boolValue;
220 }
221
222 #if FLUTTER_RUNTIME_MODE == FLUTTER_RUNTIME_MODE_DEBUG
223 // There are no ownership concerns here as all mappings are owned by the
224 // embedder and not the engine.
225 auto make_mapping_callback = [](const uint8_t* mapping, size_t size) {
226 return [mapping, size]() { return std::make_unique<fml::NonOwnedMapping>(mapping, size); };
227 };
228
229 settings.dart_library_sources_kernel =
230 make_mapping_callback(kPlatformStrongDill, kPlatformStrongDillSize);
231 #endif // FLUTTER_RUNTIME_MODE == FLUTTER_RUNTIME_MODE_DEBUG
232
233 // If we even support setting this e.g. from the command line or the plist,
234 // we should let the user override it.
235 // Otherwise, we want to set this to a value that will avoid having the OS
236 // kill us. On most iOS devices, that happens somewhere near half
237 // the available memory.
238 // The VM expects this value to be in megabytes.
239 if (settings.old_gen_heap_size <= 0) {
240 settings.old_gen_heap_size = std::round([NSProcessInfo processInfo].physicalMemory * .48 /
241 flutter::kMegaByteSizeInBytes);
242 }
243
244 // This is the formula Android uses.
245 // https://android.googlesource.com/platform/frameworks/base/+/39ae5bac216757bc201490f4c7b8c0f63006c6cd/libs/hwui/renderthread/CacheManager.cpp#45
246 CGFloat scale = [UIScreen mainScreen].scale;
247 CGFloat screenWidth = [UIScreen mainScreen].bounds.size.width * scale;
248 CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height * scale;
249 settings.resource_cache_max_bytes_threshold = screenWidth * screenHeight * 12 * 4;
250
251 // Whether to enable ios embedder api.
252 NSNumber* enable_embedder_api =
253 [mainBundle objectForInfoDictionaryKey:@"FLTEnableIOSEmbedderAPI"];
254 // Change the default only if the option is present.
255 if (enable_embedder_api) {
256 settings.enable_embedder_api = enable_embedder_api.boolValue;
257 }
258
259 return settings;
260 }

References flutter::CommandLineFromNSProcessInfo(), DoesHardwareSupportWideGamut(), FLTAssetsPathFromBundle(), FLTFrameworkBundleWithIdentifier(), FLTGetApplicationBundle(), kApplicationKernelSnapshotFileName, kPlatformStrongDill, and kPlatformStrongDillSize.

Referenced by FlutterDartProject::initWithPrecompiledDartBundle:.

## Variable Documentation

## ◆ kApplicationKernelSnapshotFileName

const char* kApplicationKernelSnapshotFileName = "kernel_blob.bin"
| static

Definition at line 28 of file FlutterDartProject.mm.

Referenced by FLTDefaultSettingsForBundle().

## ◆ kPlatformStrongDill

const FLUTTER_ASSERT_ARC uint8_t kPlatformStrongDill[]

Referenced by FLTDefaultSettingsForBundle().

## ◆ kPlatformStrongDillSize

const intptr_t kPlatformStrongDillSize

Referenced by FLTDefaultSettingsForBundle().

kApplicationKernelSnapshotFileName
static const char * kApplicationKernelSnapshotFileName
Definition: FlutterDartProject.mm:28
kPlatformStrongDillSize
const intptr_t kPlatformStrongDillSize
kPlatformStrongDill
const FLUTTER_ASSERT_ARC uint8_t kPlatformStrongDill[]
DoesHardwareSupportWideGamut
static BOOL DoesHardwareSupportWideGamut()
Definition: FlutterDartProject.mm:30
FLTGetApplicationBundle
NSBundle * FLTGetApplicationBundle()
Definition: FlutterNSBundleUtils.mm:32
flutter::CommandLineFromNSProcessInfo
fml::CommandLine CommandLineFromNSProcessInfo(NSProcessInfo *processInfoOrNil=nil)
Definition: command_line.mm:11
FLTFrameworkBundleWithIdentifier
NSBundle * FLTFrameworkBundleWithIdentifier(NSString *flutterFrameworkBundleID)
Definition: FlutterNSBundleUtils.mm:43
FLTAssetsPathFromBundle
NSString * FLTAssetsPathFromBundle(NSBundle *bundle)
Definition: FlutterNSBundleUtils.mm:61
FlutterDartProject
Definition: FlutterDartProject.mm:262