错误：没有为类“BuildContext”定义方法“ancestorInheritedElementForWidgetOfExactType”

Question

我是 Flutter 的初学者，一直坚持这一点，请帮助。

错误如下所述

插件项目：firebase_core_web 未找到。请更新 settings.gradle。

插件项目：firebase_auth_web 未找到。请更新 settings.gradle。

插件项目：cloud_firestore_web 未找到。请更新 settings.gradle。

/C:/Flutter/.pub-cache/hosted/pub.dartlang.org/provider-2.0.1+1/lib/src/provider.dart:179:19：错误：方法“inheritFromWidgetOfExactType”是'没有为类'BuildContext'定义。 -'BuildContext' 来自'package:flutter/src/widgets/framework.dart' （'/C:/Flutter/packages/flutter/lib/src/widgets/framework.dart'）。 尝试将名称更正为现有方法的名称，或定义名为“inheritFromWidgetOfExactType”的方法。 ? context.inheritFromWidgetOfExactType(type) as _Provider

              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/C:/Flutter/.pub-cache/hosted/pub.dartlang.org/provider-2.0.1+1/lib/src/provider.dart:180:19：错误：方法“ancestorInheritedElementForWidgetOfExactType”是'没有为类'BuildContext'定义。 -'BuildContext' 来自'package:flutter/src/widgets/framework.dart' （'/C:/Flutter/packages/flutter/lib/src/widgets/framework.dart'）。 尝试将名称更正为现有方法的名称，或定义名为“ancestorInheritedElementForWidgetOfExactType”的方法。 : context.ancestorInheritedElementForWidgetOfExactType(type)?.widget ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

或者请告诉我在下面这张图片中写什么来代替第 179,180 行 image description here

Answer 1

像这样去 android 文件夹更新你的 buildgradle 文件：

buildscript {
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.0'
        classpath 'com.google.gms:google-services:4.3.3'
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

然后转到Android->App->src->build gradle 检查应用插件是否存在。

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

apply plugin: 'com.android.application'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"

   def keystoreProperties = new Properties()
   def keystorePropertiesFile = rootProject.file('key.properties')
   if (keystorePropertiesFile.exists()) {
       keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
   }

   android {
    compileSdkVersion 28

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.asd.emediadesk"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

   signingConfigs {
       release {
           keyAlias keystoreProperties['keyAlias']
           keyPassword keystoreProperties['keyPassword']
           storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
           storePassword keystoreProperties['storePassword']
       }
   }
   buildTypes {
       release {
           signingConfig signingConfigs.release
       }
   }
}

flutter {
    source '../..'
}

dependencies {
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
}

apply plugin: 'com.google.gms.google-services'