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Flutter版本现在已经更新到了v1.5.4-hotfix.2，在国内也越来越火。 在之前项目中有视频播放功能，使用了flutter官方出的video_player库完成实现。flutter官方所有插件，详见https://github.com/flutter/plugins 官方的video_player，安卓是基于ExoPlayer，苹果是基于原生的AVPlayer，目前项目使用中也没什么毛病。
在闲暇之余，出于学习开发flutter plugin目的，基于腾讯云播放器封装了一个flutter视频播放器。 目前项目在开发测试阶段，还没发布到pub平台上，可通过git配置使用。
项目github地址：https://github.com/RandyWei/flt_video_player
播放器开放了部分腾讯云播放器的功能，如：倍速、静音等。
参考资料: https://github.com/An-uking/Flutter_IJKPlayer https://github.com/CaiJingLong/flutter_ijkplayer https://github.com/flutter/plugins/tree/master/packages/video_player
在项目开发过程中碰到了以下问题，作了一下总结：
1、出现label标签冲突相关问题，如下错误
Attribute application@label value=(flutter_plugin_demo_example) from AndroidManifest.xml:13:9-52
is also present at [LiteAVSDK_Player_6.3.7089.aar] AndroidManifest.xml:19:9-41 value=(@string/app_name).
Suggestion: add 'tools:replace="android:label"' to <application> element at AndroidManifest.xml:11:5-35:19 to override.
这个错误是在安卓端出现的，因为使用了LiteAVSDK，类似这种使用了各种第三方库包含android:label的，所以冲突了
解决办法：其实错误代码提示也很是明确，或者直接上谷歌去百度一下就可以得到答案，在mainfest Application标签中添加tools:relpace=”label”即可。
2、在使用EventChannel进行Flutter和Native通信过程中出现以下错误：
E/EventChannel#flutter_plugin_demo.event.status(15177): Failed to open event stream
E/EventChannel#flutter_plugin_demo.event.status(15177): java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter o
E/EventChannel#flutter_plugin_demo.event.status(15177): at com.chinahrt.flutter_plugin_demo2.FlutterPluginDemo2Plugin$onMethodCall$1.onListen(Unknown Source:2)
E/EventChannel#flutter_plugin_demo.event.status(15177): at io.flutter.plugin.common.EventChannel$IncomingStreamRequestHandler.onListen(EventChannel.java:181)
E/EventChannel#flutter_plugin_demo.event.status(15177): at io.flutter.plugin.common.EventChannel$IncomingStreamRequestHandler.onMessage(EventChannel.java:160)
E/EventChannel#flutter_plugin_demo.event.status(15177): at io.flutter.view.FlutterNativeView$PlatformMessageHandlerImpl.handleMessageFromDart(FlutterNativeView.java:188)
E/EventChannel#flutter_plugin_demo.event.status(15177): at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:202)
E/EventChannel#flutter_plugin_demo.event.status(15177): at android.os.MessageQueue.nativePollOnce(Native Method)
E/EventChannel#flutter_plugin_demo.event.status(15177): at android.os.MessageQueue.next(MessageQueue.java:326)
E/EventChannel#flutter_plugin_demo.event.status(15177): at android.os.Looper.loop(Looper.java:160)
E/EventChannel#flutter_plugin_demo.event.status(15177): at android.app.ActivityThread.main(ActivityThread.java:6718)
E/EventChannel#flutter_plugin_demo.event.status(15177): at java.lang.reflect.Method.invoke(Native Method)
E/EventChannel#flutter_plugin_demo.event.status(15177): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
E/EventChannel#flutter_plugin_demo.event.status(15177): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
I/flutter (15177): ══╡ EXCEPTION CAUGHT BY SERVICES LIBRARY ╞══════════════════════════════════════════════════════════
I/flutter (15177): The following PlatformException was thrown while activating platform stream on channel
I/flutter (15177): flutter_plugin_demo.event.status:
I/flutter (15177): PlatformException(error, Parameter specified as non-null is null: method
I/flutter (15177): kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter o, null)
I/flutter (15177):
I/flutter (15177): When the exception was thrown, this was the stack:
I/flutter (15177): #0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:564:7)
I/flutter (15177): #1 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:302:33)
I/flutter (15177): <asynchronous suspension>
I/flutter (15177): #2 EventChannel.receiveBroadcastStream.<anonymous closure> (package:flutter/src/services/platform_channel.dart:490:29)
I/flutter (15177): <asynchronous suspension>
I/flutter (15177): #7 VideoPlayerController.initialize (package:flutter_plugin_demo2/video_player.dart:33:10)
I/flutter (15177): <asynchronous suspension>
I/flutter (15177): #8 _MyAppState.initState (package:flutter_plugin_demo2_example/main.dart:25:9)
I/flutter (15177): #9 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3846:58)
I/flutter (15177): #10 ComponentElement.mount (package:flutter/src/widgets/framework.dart:3711:5)
I/flutter (15177): #11 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2956:14)
I/flutter (15177): #12 Element.updateChild (package:flutter/src/widgets/framework.dart:2759:12)
I/flutter (15177): #13 RenderObjectToWidgetElement._rebuild (package:flutter/src/widgets/binding.dart:933:16)
I/flutter (15177): #14 RenderObjectToWidgetElement.mount (package:flutter/src/widgets/binding.dart:904:5)
I/flutter (15177): #15 RenderObjectToWidgetAdapter.attachToRenderTree.<anonymous closure> (package:flutter/src/widgets/binding.dart:850:17)
I/flutter (15177): #16 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2253:19)
I/flutter (15177): #17 RenderObjectToWidgetAdapter.attachToRenderTree (package:flutter/src/widgets/binding.dart:849:13)
I/flutter (15177): #18 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding&WidgetsBinding.attachRootWidget (package:flutter/src/widgets/binding.dart:736:7)
I/flutter (15177): #19 runApp (package:flutter/src/widgets/binding.dart:780:7)
I/flutter (15177): #20 main (package:flutter_plugin_demo2_example/main.dart:8:16)
I/flutter (15177): #21 _runMainZoned.<anonymous closure>.<anonymous closure> (dart:ui/hooks.dart:189:25)
I/flutter (15177): #26 _runMainZoned.<anonymous closure> (dart:ui/hooks.dart:180:5)
I/flutter (15177): #27 _startIsolate.<anonymous closure> (dart:isolate/runtime/libisolate_patch.dart:300:19)
I/flutter (15177): #28 _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:171:12)
I/flutter (15177): (elided 8 frames from package dart:async)
I/flutter (15177): ════════════════════════════════════════════════════════════════════════════════════════════════════
这个问题还是出现在安卓平台上，因为安卓项目使用了kotlin支持，在写kotlin代码实现EventChannel.StreamHandler时
override fun onListen(o: Any?, sink: EventChannel.EventSink?) {
}
override fun onCancel(o: Any?) {
}参数应该可空。因误写成不可空，导致报错。 所以解决办法就是加?就可以
3、在iOS项目podspec上配置腾讯云播放器TXLiteAVSDK_Player支持时，出现以下问题
Undefined symbols for architecture x86_64:
"vtable for __cxxabiv1::__si_class_type_info", referenced from:
typeinfo for bssl::(anonymous namespace)::ECKeyShare in TXLiteAVSDK_Player(ssl_key_share.o)
typeinfo for bssl::(anonymous namespace)::X25519KeyShare in TXLiteAVSDK_Player(ssl_key_share.o)
NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
"_sqlite3_column_text", referenced from:
_qcloud_ijktsdb_meta_select in TXLiteAVSDK_Player(ijktsdb.o)
"_sqlite3_bind_blob", referenced from:
_qcloud_ijktsdb_insert in TXLiteAVSDK_Player(ijktsdb.o)
"_sqlite3_bind_text", referenced from:
_qcloud_ijktsdb_select in TXLiteAVSDK_Player(ijktsdb.o)
_ijktsdb_check in TXLiteAVSDK_Player(ijktsdb.o)
_qcloud_ijktsdb_insert in TXLiteAVSDK_Player(ijktsdb.o)
_qcloud_ijktsdb_meta_select in TXLiteAVSDK_Player(ijktsdb.o)
_qcloud_ijktsdb_meta_insert in TXLiteAVSDK_Player(ijktsdb.o)
"_sqlite3_column_bytes", referenced from:
_qcloud_ijktsdb_select in TXLiteAVSDK_Player(ijktsdb.o)
_ijktsdb_check in TXLiteAVSDK_Player(ijktsdb.o)
"_sqlite3_column_blob", referenced from:
_qcloud_ijktsdb_select in TXLiteAVSDK_Player(ijktsdb.o)
"_sqlite3_errcode", referenced from:
_databaseError in TXLiteAVSDK_Player(ijktsdb.o)
"_sqlite3_close", referenced from:
_qcloud_ijktsdb_open in TXLiteAVSDK_Player(ijktsdb.o)
_qcloud_ijktsdb_close in TXLiteAVSDK_Player(ijktsdb.o)
使用framwork配置无论怎样都配置不成功，如果有大佬知道怎么配置的，可以教教
最后还是使用了pod：s.dependency 'TXLiteAVSDK_Player' 配置成功了。
参考资料： https://guides.cocoapods.org/syntax/podspec.html#dependency
4、在开发过程中出现以下错误：
Exception: ideviceinfo returned an error:
ERROR: Could not connect to lockdownd, error code -8
#0 IMobileDevice.getInfoForDevice (package:flutter_tools/src/ios/mac.dart:141:9)
<asynchronous suspension>
#1 IOSDevice.getAttachedDevices (package:flutter_tools/src/ios/devices.dart:156:55)
<asynchronous suspension>
#2 IOSDevices.pollingGetDevices (package:flutter_tools/src/ios/devices.dart:110:57)
#3 PollingDeviceDiscovery.devices (package:flutter_tools/src/device.dart:186:52)
<asynchronous suspension>
#4 DeviceManager.getAllConnectedDevices (package:flutter_tools/src/device.dart:114:46)
<asynchronous suspension>
#5 DeviceValidator.validate (package:flutter_tools/src/doctor.dart:705:54)
<asynchronous suspension>
#6 Doctor.startValidatorTasks (package:flutter_tools/src/doctor.dart:129:52)
#7 Doctor.diagnose (package:flutter_tools/src/doctor.dart:200:41)
#8 _AsyncAwaitCompleter.start (dart:async-patch/async_patch.dart:49:6)
#9 Doctor.diagnose (package:flutter_tools/src/doctor.dart:190:24)
#10 DoctorCommand.runCommand (package:flutter_tools/src/commands/doctor.dart:48:39)
#11 _AsyncAwaitCompleter.start (dart:async-patch/async_patch.dart:49:6)
#12 DoctorCommand.runCommand (package:flutter_tools/src/commands/doctor.dart:34:42)
#13 FlutterCommand.verifyThenRunCommand (package:flutter_tools/src/runner/flutter_command.dart:559:18)
#14 _asyncThenWrapperHelper.<anonymous closure> (dart:async-patch/async_patch.dart:77:64)
#15 _rootRunUnary (dart:async/zone.dart:1132:38)
#16 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
#17 _FutureListener.handleValue (dart:async/future_impl.dart:126:18)
#18 Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:639:45)
#19 Future._propagateToListeners (dart:async/future_impl.dart:668:32)
#20 Future._complete (dart:async/future_impl.dart:473:7)
#21 _SyncCompleter.complete (dart:async/future_impl.dart:51:12)
#22 _AsyncAwaitCompleter.complete.<anonymous closure> (dart:async-patch/async_patch.dart:33:20)
#23 _rootRun (dart:async/zone.dart:1124:13)
#24 _CustomZone.run (dart:async/zone.dart:1021:19)
#25 _CustomZone.bindCallback.<anonymous closure> (dart:async/zone.dart:947:23)
#26 _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#27 _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
#28 _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:115:13)
#29 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:172:5)
执行命令： ideviceinfo -d出现如下错误
13:18:45 idevice.c:295 idevice_connect(): ERROR: Connecting to usbmuxd failed: -9 (Bad file descriptor)
13:18:45 lockdown.c:663 lockdownd_client_new(): could not connect to lockdownd (device 1a95bb66796dad5ebf6a99d1c87101b5c2214963)
13:18:45 lockdown.c:698 lockdownd_client_new_with_handshake(): failed to create lockdownd client.
ERROR: Could not connect to lockdownd, error code -8
关于”Could not connect to lockdownd”这个错误，网上出现了很多解决办法，但每个人碰到的error code -8，错误码都不一样。有部分解决办法就是修改权限，对于错误码为 -8 的，一直没有搜到相关解决办法。折腾了一天，其实原因是，开发过程中，我碰到了手机，导致手机数据线松了，然后我更换了一个USB接口，总之是因为手机和电脑没有连接好。如果有碰到这个问题，换个接口，然后撤销iphone手机和电脑的信任，直到连接电脑时弹出信任授权对话框，才算是正常连接成功。一旦出现这个错误，连安卓设备都运行不了。
5、
Assertion failed: (AMDeviceIsPaired(device)), function handle_device, file /tmp/ios-deploy-20181117-87168-1goz8ak/ios-deploy-1.9.4/src/ios-deploy/ios-deploy.m, line 1598.
Could not install build/ios/iphoneos/Runner.app on 1a95bb66796dad5ebf6a99d1c87101b5c2214963.
Try launching Xcode and selecting "Product > Run" to fix the problem:
open ios/Runner.xcworkspace
Error launching application on iPhone (5).
出现这个错误，直接按提示使用Xcode运行一下项目即可。
6、还有最后一个严重的内存泄漏的问题
错误日志：Signal 11 was raised.
在iOS实现将画面数据传送到Flutter，使用到了CVPixelBufferRef数据。对于这块目前不是很清楚，大概是因为线程安全的问题，在腾讯云播放器回调的数据，随时可能会被释放，而在Flutter回调中使用了已被释放的数据，出现了问题。最后参考了ijk代码，使用了OSAtomicCompareAndSwapPtrBarrier对数据进行验证比较得以解决，对于这个OSAtomicCompareAndSwapPtrBarrier方法也不是很理解，如果有大佬了解的，可以教教我。