[Flutter 实战] Rejecting re-init on previously-failed class java.lang.Class<com.yalantis.ucrop.UCro...

在此记录项目中所遇到问题及解决方案

Rejecting re-init on previously-failed class java.lang.Class<com.yalantis.ucrop.UCropActivity>: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v7/app/AppCompatActivity

在android/app/build.gradle文件中的dependencies节添加

implementation 'com.android.support:appcompat-v7:28.0.0'

如果在编译阶段不通过，可以android.support库换成AndroidX

1.在android/gradle/wrapper/gradle-wrapper.properties文件中把distributionUrl参数换成:

distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.2-all.zip

2. 在android/build.gradle文件中把

dependencies {
    classpath 'com.android.tools.build:gradle:3.2.1'
}

换成

dependencies {
    classpath 'com.android.tools.build:gradle:3.3.0'
}

3. 在android/gradle.properties文件中加

android.enableJetifier=true
android.useAndroidX=true
In android/app/build.gradle:

4. compileSdkVersion 和 targetSdkVersion 必须是28以上.

5. 在android/app/build.gradle文件中

把

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

换成

testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

把

androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

换成

androidTestImplementation 'androidx.test:runner:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'

官方指南：
How to migrate a Flutter app to AndroidX