gradle问题

1, my gradle version is 4.6 .

in project.gradle :

change

dependencies {

     classpath 'com.android.tools.build:gradle:3.0.0'

     ```
    // NOTE: Do not place your application dependencies here; they belong

    // in the individual module build.gradle files

}

to:

dependencies {

    classpath 'com.android.tools.build:gradle:3.2.1'

    ```
    // NOTE: Do not place your application dependencies here; they belong

    // in the individual module build.gradle files

}

2, delete 

<uses-sdk android:minSdkVersion="21" />

this code line in manifest.xml

3, change `compile` to `implementation` in app.gradle(Module gradle)