问题具体描述： AS断点发现值已经传到了后端，后端断点（Spring）发现key "B"的值为空字符串""，flutter传参的数据结构为：
{"A":"111", "B":["222","333"] }后端取值发现 "B"的值取不到，报错显示的是"B[]"的参数问题 。 解决方式： 方式1： 后端，经试验后端取值key 从"B"改为"B[]" ,正常运行。 方式2：flutter 端，其他解决方式参考：https://xingdi.me/archives/50.html
控制台错误如下：
FAILURE: Build failed with an exception. * What went wrong: Could not determine the dependencies of task ':app:compileReleaseJavaWithJavac'. > Could not resolve all dependencies for configuration ':app:releaseRuntimeClasspath'. > Conflict(s) found for the following module(s): - com.squareup.okhttp3:okhttp between versions 3.10.0 and 3.3.0 - com.squareup.okio:okio between versions 1.14.0 and 1.13.0 Run with: --scan or :app:dependencyInsight --configuration releaseRuntimeClasspath --dependency com.squareup.okhttp3:okhttp to get more insight on how to solve the conflict. * Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights. * Get more help at https://help.gradle.org BUILD FAILED in 1s Running Gradle task 'assembleRelease'... Running Gradle task 'assembleRelease'... Done 2.2s Gradle task assembleRelease failed with exit code 1解决方式：强制在android/app/build.gradle中指定依赖
configurations.all { resolutionStrategy { force 'com.squareup.okhttp3:okhttp:3.10.0' force 'com.squareup.okio:okio:1.14.0' } }1.file_preview（在线文件预览） （1）打开时出现如下问题：
E/MethodChannel#com.zzaning.file_preview(23244): Failed to handle method call E/MethodChannel#com.zzaning.file_preview(23244): android.content.ActivityNotFoundException: Unable to find explicit activity class {com.demo.myapp/zzaning.com.filepreview.FileDisplayActivity}; have you declared this activity in your AndroidManifest.xml? E/MethodChannel#com.zzaning.file_preview(23244): at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1944) E/MethodChannel#com.zzaning.file_preview(23244): at android.app.Instrumentation.execStartActivity(Instrumentation.java:1622) E/MethodChannel#com.zzaning.file_preview(23244): at android.app.ContextImpl.startActivity(ContextImpl.java:882) E/MethodChannel#com.zzaning.file_preview(23244): at android.app.ContextImpl.startActivity(ContextImpl.java:859) E/MethodChannel#com.zzaning.file_preview(23244): at android.content.ContextWrapper.startActivity(ContextWrapper.java:372) E/MethodChannel#com.zzaning.file_preview(23244): at zzaning.com.filepreview.FileDisplayActivity.show(FileDisplayActivity.java:91) E/MethodChannel#com.zzaning.file_preview(23244): at zzaning.com.filepreview.FilePreviewPlugin.onMethodCall(FilePreviewPlugin.java:56) E/MethodChannel#com.zzaning.file_preview(23244): at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:226) E/MethodChannel#com.zzaning.file_preview(23244): at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85) E/MethodChannel#com.zzaning.file_preview(23244): at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:631) E/MethodChannel#com.zzaning.file_preview(23244): at android.os.MessageQueue.nativePollOnce(Native Method) E/MethodChannel#com.zzaning.file_preview(23244): at android.os.MessageQueue.next(MessageQueue.java:325) E/MethodChannel#com.zzaning.file_preview(23244): at android.os.Looper.loop(Looper.java:149) E/MethodChannel#com.zzaning.file_preview(23244): at android.app.ActivityThread.main(ActivityThread.java:6840) E/MethodChannel#com.zzaning.file_preview(23244): at java.lang.reflect.Method.invoke(Native Method) E/MethodChannel#com.zzaning.file_preview(23244): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) E/MethodChannel#com.zzaning.file_preview(23244): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:886) E/flutter (23244): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: PlatformException(error, Unable to find explicit activity class {com.demo.myapp/zzaning.com.filepreview.FileDisplayActivity}; have you declared this activity in your AndroidManifest.xml?, null) E/flutter (23244): #0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:569:7) E/flutter (23244): #1 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:156:18) E/flutter (23244): <asynchronous suspension> E/flutter (23244): #2 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:329:12) E/flutter (23244): #3 FilePreview.openFile (package:file_preview/file_preview.dart:11:42) E/flutter (23244): #4 _FilePickerUtilState._typeWidget.<anonymous closure> (package:plascloud_flutter/util/file_picker_util.dart:360:25) E/flutter (23244): #5 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:779:19) E/flutter (23244): #6 _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:862:36) E/flutter (23244): #7 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24) E/flutter (23244): #8 TapGestureRecognizer.handleTapUp (package:flutter/src/gestures/tap.dart:504:11) E/flutter (23244): #9 BaseTapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:282:5) E/flutter (23244): #10 BaseTapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:217:7) E/flutter (23244): #11 PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:475:9) E/flutter (23244): #12 PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:76:12) E/flutter (23244): #13 PointerRouter._dispatchEventToRoutes.<anonymous closure> (package:flutter/src/gestures/pointer_router.dart:122:9) E/flutter (23244): #14 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:379:8) E/flutter (23244): #15 PointerRouter._dispatchEventToRoutes (package:flutter/src/gestures/pointer_router.dart:120:18) E/flutter (23244): #16 PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:106:7) E/flutter (23244): #17 GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:218:19) E/flutter (23244): #18 GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22) E/flutter (23244): #19 GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7) E/flutter (23244): #20 GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7) E/flutter (23244): #21 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7) E/flutter (23244): #22 _rootRunUnary (dart:async/zone.dart:1196:13) E/flutter (23244): #23 _CustomZone.runUnary (dart:async/zone.dart:1085:19) E/flutter (23244): #24 _CustomZone.runUnaryGuarded (dart:async/zone.dart:987:7) E/flutter (23244): #25 _invoke1 (dart:ui/hooks.dart:275:10) E/flutter (23244): #26 _dispatchPointerDataPacket (dart:ui/hooks.dart:184:5)解决方法：在flutter的AndroidManifest.xml中加入
<activity android:name="zzaning.com.filepreview.FileDisplayActivity" />（2）加载时出现如下：
I/ViewRootImpl(24083): WindowInputEventReceiver onInputEvent!! KeyCode is 4, action is 0 I/ViewRootImpl(24083): ViewPostImeInputStage processKeyEvent back key, this android.view.ViewRootImpl$ViewPostImeInputStage@329ac9b I/ViewRootImpl(24083): WindowInputEventReceiver onInputEvent!! KeyCode is 4, action is 1 I/ViewRootImpl(24083): ViewPostImeInputStage processKeyEvent back key, this android.view.ViewRootImpl$ViewPostImeInputStage@329ac9b I/MobclickAgent(24083): Extend current session: C225DA6B4A617DBBBE388BA9C3B48CA9 W/System.err(24083): java.nio.channels.ClosedChannelException W/System.err(24083): at sun.nio.ch.FileLockImpl.release(FileLockImpl.java:58) W/System.err(24083): at com.tencent.common.plugin.QBPluginServiceImpl.deletePidFile(TbsJavaCore:3464) W/System.err(24083): at com.tencent.common.plugin.QBPluginServiceImpl.stopDownloadPlugin(TbsJavaCore:1466) W/System.err(24083): at com.tencent.common.plugin.QBPluginProxy.stopDownloadPlugin(TbsJavaCore:424) W/System.err(24083): at com.tencent.common.plugin.QBPluginSystem$2.handleMessage(TbsJavaCore:1858) W/System.err(24083): at android.os.Handler.dispatchMessage(Handler.java:106) W/System.err(24083): at android.os.Looper.loop(Looper.java:192) W/System.err(24083): at android.os.HandlerThread.run(HandlerThread.java:65) I/qtaguid (24083): Untagging socket 116 failed errno=-22 E/QB_DOWN::DownloadWorker(24083): ERR [run] E/QB_DOWN::DownloadWorker(24083): java.net.SocketException: Socket closed E/QB_DOWN::DownloadWorker(24083): at java.net.SocketInputStream.read(SocketInputStream.java:203) E/QB_DOWN::DownloadWorker(24083): at java.net.SocketInputStream.read(SocketInputStream.java:139) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.okio.Okio$2.read(Okio.java:136) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.okio.AsyncTimeout$2.read(AsyncTimeout.java:211) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:306) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:300) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.okio.RealBufferedSource.readUtf8LineStrict(RealBufferedSource.java:196) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.http.Http1xStream.readResponse(Http1xStream.java:186) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.http.Http1xStream.readResponseHeaders(Http1xStream.java:127) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.http.HttpEngine.readNetworkResponse(HttpEngine.java:756) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.http.HttpEngine.readResponse(HttpEngine.java:628) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:471) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:407) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getHeaders(HttpURLConnectionImpl.java:163) E/QB_DOWN::DownloadWorker(24083): at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getHeaderFields(HttpURLConnectionImpl.java:223) E/QB_DOWN::DownloadWorker(24083): at com.tencent.common.http.HttpRequesterBase.parseResponseHeaders(TbsJavaCore:728) E/QB_DOWN::DownloadWorker(24083): at com.tencent.common.http.HttpRequesterBase.a(TbsJavaCore:198) E/QB_DOWN::DownloadWorker(24083): at com.tencent.common.http.HttpRequesterBase.a(TbsJavaCore:187) E/QB_DOWN::DownloadWorker(24083): at com.tencent.common.http.HttpRequesterBase.execute(TbsJavaCore:81) E/QB_DOWN::DownloadWorker(24083): at com.tencent.mtt.browser.download.engine.network.DownloadConnection.execute(TbsJavaCore:173) E/QB_DOWN::DownloadWorker(24083): at com.tencent.mtt.browser.download.engine.core.DownloadWorker.run(TbsJavaCore:254) E/QB_DOWN::DownloadWorker(24083): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) E/QB_DOWN::DownloadWorker(24083): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) E/QB_DOWN::DownloadWorker(24083): at com.tencent.mtt.browser.download.engine.core.DownloadThreadPolicy$2.run(TbsJavaCore:51) I/MobclickAgent(24083): Extend current session: C225DA6B4A617DBBBE388BA9C3B48CA9 I/qtaguid (24083): Untagging socket 116 failed errno=-22 W/System.err(24083): android.content.pm.PackageManager$NameNotFoundException: com.tencent.mtt W/System.err(24083): at android.app.ApplicationPackageManager.getPackageInfoAsUser(ApplicationPackageManager.java:193) W/System.err(24083): at android.app.ApplicationPackageManager.getPackageInfo(ApplicationPackageManager.java:149) W/System.err(24083): at com.tencent.common.utils.MttLoader.getBrowserInfo(TbsJavaCore:442) W/System.err(24083): at com.tencent.mtt.external.reader.MttFileReaderWrapper.<init>(TbsJavaCore:151) W/System.err(24083): at com.tencent.tbs.tbsshell.partner.reader.c.a(TbsJavaCore:418) W/System.err(24083): at com.tencent.tbs.tbsshell.partner.reader.c.a(TbsJavaCore:129) W/System.err(24083): at com.tencent.tbs.reader.TbsReader.openFile(TbsJavaCore:59) W/System.err(24083): at java.lang.reflect.Method.invoke(Native Method) W/System.err(24083): at com.tencent.smtt.export.external.DexLoader.invokeMethod(Unknown Source:14) W/System.err(24083): at com.tencent.smtt.sdk.ReaderWizard.openFile(Unknown Source:44) W/System.err(24083): at com.tencent.smtt.sdk.TbsReaderView.openFile(Unknown Source:61) W/System.err(24083): at zzaning.com.filepreview.SuperFileView2.displayFile(SuperFileView2.java:80) W/System.err(24083): at zzaning.com.filepreview.FileDisplayActivity$2.onResponse(FileDisplayActivity.java:155) W/System.err(24083): at retrofit2.ExecutorCallAdapterFactory$ExecutorCallbackCall$1$1.run(ExecutorCallAdapterFactory.java:68) W/System.err(24083): at android.os.Handler.handleCallback(Handler.java:790) W/System.err(24083): at android.os.Handler.dispatchMessage(Handler.java:99) W/System.err(24083): at android.os.Looper.loop(Looper.java:192) W/System.err(24083): at android.app.ActivityThread.main(ActivityThread.java:6840) W/System.err(24083): at java.lang.reflect.Method.invoke(Native Method) W/System.err(24083): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) W/System.err(24083): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:886) E/superFileLog(24083): ****************************************************5045 W/down-pool-1(24083): type=1400 audit(0.0:35625982): avc: denied { read } for name="u:object_r:net_dns_prop:s0" dev="tmpfs" ino=15543 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:object_r:net_dns_prop:s0 tclass=file permissive=0 E/libc (24083): Access denied finding property "net.dns1"解决方式：参考https://blog.csdn.net/tung214/article/details/72734086
2.使用插件 flutter_image_compress: ^0.7.0 打包报错： ``
FAILURE: Build failed with an exception. * What went wrong: A problem occurred configuring project ':flutter_image_compress'. > Could not resolve all artifacts for configuration ':flutter_image_compress:classpath'. > Could not resolve org.apache.httpcomponents:httpcore:4.4.6. Required by: project :flutter_image_compress > org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.50 > de.undercouch:gradle-download-task:3.4.3 > org.apache.httpcomponents:httpclient:4.5.3 > Could not resolve org.apache.httpcomponents:httpcore:4.4.6. > Could not get resource 'https://dl.google.com/dl/android/maven2/org/apache/httpcomponents/httpcore/4.4.6/httpcore-4.4.6.pom'. > Could not GET 'https://dl.google.com/dl/android/maven2/org/apache/httpcomponents/httpcore/4.4.6/httpcore-4.4.6.pom'. > Connect to dl.google.com:443 [dl.google.com/203.208.40.33] failed: Read timed out > Could not get unknown property 'android' for project ':flutter_image_compress' of type org.gradle.api.Project. * Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights. * Get more help at https://help.gradle.org BUILD FAILED in 1m 44s Running Gradle task 'assembleRelease'... Running Gradle task 'assembleRelease'... Done 105.2s Gradle task assembleRelease failed with exit code 1`` 解决方式: （1） classpath “org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.72”（见作者的该项目GitHub） （2）参看下面的步骤：
1、修改版本，修改android｛｝ compileSdkVersion 22(或者更高) 2、在android｛｝中添加 useLibrary 'org.apache.http.legacy' 3、在dependencies｛｝中添加 compile 'org.apache.httpcomponents:httpcore:4.4.2' ———————————————— 原文链接：https://blog.csdn.net/danwuxie/article/details/84500818