1-在build下面添加dataBinding功能:

android {
...
buildFeatures {
        dataBinding true
    }
...
}

2-将匕首版本改为2.31.2

annotationProcessor "com.google.dagger:dagger-compiler:$daggerVersion"
implementation "com.google.dagger:dagger:$daggerVersion"

3- butterKnife版本也更改为10.2.3

implementation 'com.jakewharton:butterknife:10.2.3'
annotationProcessor 'com.jakewharton:butterknife-compiler:10.2.3'

出现此警告是因为

    dataBinding {
        enabled=true
    }

    viewBinding {
        enabled=true
    }

这种代码风格已弃用，并将从gradle版本5中删除 现在如果你仍然想使用这个，那么你可以使用androidx遗留的支持依赖项

在应用程序级别build.gradle

implementation 'androidx.legacy:legacy-support-v4:1.0.0'

否则，您可以使用新的代码样式来启用数据绑定和视图绑定

像这样

android {

  buildFeatures {

         dataBinding = true

         // for view binding:
         // viewBinding = true
    }
}

1-在build下面添加dataBinding功能:

android {
...
buildFeatures {
        dataBinding true
    }
...
}

2-将匕首版本改为2.31.2

annotationProcessor "com.google.dagger:dagger-compiler:$daggerVersion"
implementation "com.google.dagger:dagger:$daggerVersion"

3- butterKnife版本也更改为10.2.3

implementation 'com.jakewharton:butterknife:10.2.3'
annotationProcessor 'com.jakewharton:butterknife-compiler:10.2.3'

如果您正在寻找新的特性viewBinding，可以试试Groovy的这个特性

android {
    ...
    buildFeatures {
        viewBinding true
    }
}

这是给Kotlin的

android {
    ...
    buildFeatures {
        viewBinding true
    }
}

但是，要使用默认的android数据绑定

android {
    ...
    buildFeatures {
        dataBinding true
    }
}

另外，要注意使用

kapt "com.android.databinding:compiler:4.0.0"

你必须在gradle模块中添加buildFeatures

android {
    buildFeatures{
        dataBinding true
    }
}

例子:

plugins {
    id 'com.android.application'
}

android {
    compileSdkVersion 30

    defaultConfig {
        applicationId "com.demo"
        minSdkVersion 21
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    buildFeatures{
        dataBinding true
    }
}

dependencies {

    implementation 'androidx.appcompat:appcompat:1.3.0'
    implementation 'com.google.android.material:material:1.3.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
    implementation 'org.jetbrains:annotations:15.0'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}

buildFeatures {

        //just for dataBinding ，It has nothing to do with viewBinding 
        dataBinding = true

        //just for viewBinding ，It has nothing to do with dataBinding
        viewBinding = true
    }

看看上面的注释，应该很清楚了