无法通过子模块的传递使用找到 lib

问题描述

Android Studio 3.4.2

Android Studio 3.4.2

我有使用模块 mytransport 的主项目(应用程序)，如下所示:

I has main project (app) that use module mytransport like this:

app/build.gradle

dependencies {
    annotationProcessor "org.androidannotations:androidannotations:$AAVersion"

    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation('com.crashlytics.sdk.android:crashlytics:2.7.0@aar') { transitive = true; }
    implementation 'com.google.android.material:material:1.1.0-alpha07'
    implementation "org.androidannotations:androidannotations-api:$AAVersion"

    implementation project(':mytransport')

}

在 mytransport/build.gradle:

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.google.code.gson:gson:2.8.5'

}

在 mytransport 代码中，我成功使用了这样的代码:

In mytransport code I success use code like this:

在 MyProjectmytransportsrcmainjavacommycompanyandroidmytransportutilMyUtil.java

片段:

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;

public class JSONUtil {
private static GsonBuilder gsonbuilder = new GsonBuilder();

不错.

现在我想在主应用程序中使用 gson 库.所以在主应用程序我试试这个

Now I want in main app to use gson lib. So in main app I try this in

MyProjectandroidMyProjectappsrcmainjavacommycompanyandroidmyprojectmainMainApp.java

片段

import android.app.Application;
import android.content.Context;
public class MainApp extends Application {

private static GsonBuilder gsonbuilder = new GsonBuilder();

但我得到编译错误:

Cannot resolve symbol 'GsonBuilder'

为什么在主应用中找不到gson lib?我通过 mytransport 模块使用它TRANSITIVE

Why it can't find gson lib in main app? I use it TRANSITIVE by mytransport module

推荐答案

使用 api 而不是 implementation.

在mytransport/build.gradle:

dependencies {
   //...
   api 'com.google.code.gson:gson:2.8.5'
}

只是一个例子.

在library/build.gradle:

dependencies {
    api project(':libraryA')
}

在app/build.gradle:

dependencies {
    api project(':library')
}

在您的应用中，您将能够访问 both library 和 libraryA.

In your app you will be able to access both library and libraryA.

使用实现配置:

在library/build.gradle:

dependencies {
    implementation project(':libraryA')
}

在app/build.gradle:

dependencies {
    implementation project(':library')
}

在这种情况下，在您的应用中，您无法访问 libraryA 方法.

In this case in your app you can't access the libraryA methods.