I can only solve dependencies by using'+' in Library versions

Question

22 Dec 2017 Error that occurred when with Offlinework

After switching to Online Work

ORIGINAL: I’ve been trying to avoid doing it that way:

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.android.support:appcompat-v7:26.+'

because the use of '+' is discouraged, but Gradle can never "solve dependencies" if I use

...v7:26.1.1 ou v7:27.0.2(com os devidos ajustes)

or any other version you can find on the web.

I put down the full code of the build.Radle of the App (in 1º) and the build.Radle of the project (in 2º).

I ask you: to) How to proceed to avoid the '+'? b) Where can I find the versions (26.x.x, for example) that exist and can be compiled?

apply plugin: 'com.android.application'

android {
    compileSdkVersion 26//23
    buildToolsVersion '26.0.3'

    defaultConfig {
        applicationId "com.example.android.LearnEnglish"
        minSdkVersion 15
        targetSdkVersion 26//23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

repositories {
    jcenter()
    google()
    //maven { url "https://maven.google.com" } Este só se usa com Gradle abaixo de 4.1
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.android.support:appcompat-v7:26.+'
    //compile 'com.android.support:support-v4.app.ActivityCompat'//com.android.support:support-compat:+'
    //compile 'com.android.support:support-v4:23.3.0'
    //compile 'com.android.support:design:23.3.0'
    compile 'com.android.support.constraint:constraint-layout:1.0.2'
    testCompile 'junit:junit:4.12'
    /*compile fileTree(dir: 'libs', include: ['*.jar'])
        compile 'com.android.support:appcompat-v7:23.3.0'
        compile 'com.android.support:support-v4:23.3.0'
        compile 'com.android.support:design:23.3.0'
        compile 'com.android.support.constraint:constraint-layout:1.0.2'
        testCompile 'junit:junit:4.12'*/
}

(project:)

buildscript {
    repositories {
        // Gradle 4.1 and higher include support for Google's Maven repo using
        // the google() method. And you need to include this repo to download
        // Android plugin 3.0.0 or higher.
        jcenter()
        google()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.1'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
        google()


    }
}

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

Answer 1

It is not recommended to use the "+", can cause errors, Android Studio warns about it in dependencies.

To) How to proceed to avoid the '+'?

Use all support libraries in the same version, I recommend 26.1.0 or similar (version 27.0.2 ta with some problems), 'compileSDKVersion': 26, 'buildToolsVersion':26.1.0 and all support library dependencies. ex:

compile 'com.android.support:appcompat-v7:26.1.0'
compile 'com.android.support:design:26.1.0'
compile 'com.android.support:recyclerview-v7:26.1.0'

B) Where can I find the versions (26.x.x, for example) that exist and can be compiled?

Personally I recommend you to look in SDK Manager, you will see the necessary updates, installed versions, etc...

Answer 2

When using the support libraries, in those that are related to each other, you must use the same revision number.

Preferably you should use the last revision, which on this date is version 27.0.2.

In Support Library Packages you find the list of all libraries and their identifier to be used in Gradle.

You can find the lists and details of the most recent revisions on Recent Support Library Revisions.