Could not resolve com.android.support:design:26.1.0 - android-gradle-plugin

Question

I have been having this problem for quite a while, that my com.android.support:design:26.1.0 fails me and I have no clue what to change anymore.
These are my files for module gradle.
Build.gradle (app)
apply plugin: 'com.android.application'
android {
compileSdkVersion 26
buildToolsVersion '26.0.2'
defaultConfig {
applicationId "com.xxx.yyy"
minSdkVersion 16
targetSdkVersion 26
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:26.1.0'
implementation 'com.android.support.constraint:constraint-layout:1.0.2'
implementation 'com.android.support:design:26.1.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.1'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
compile 'com.android.support:support-v4:26.1.0'
compile 'com.google.android.gms:play-services-vision:9.4.0'
// compile 'com.android.support:design:26.1.0'
}
//apply plugin: 'com.google.gms.google-services'
The project gradle file
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
google()
jcenter({ url "http://jcenter.bintray.com/" })
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.1'
// classpath 'com.google.gms:google-services:3.2.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
google()
jcenter({ url "http://jcenter.bintray.com/" })
maven { url "https://maven.google.com" }
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
Error:Unable to resolve dependency for
':app#releaseUnitTest/compileClasspath': Could not resolve
com.android.support:design:26.1.0.
Error:Unable to resolve dependency
for ':app#release/compileClasspath': Could not resolve
com.android.support:design:26.1.0.
Error:Unable to resolve dependency
for ':app#debugUnitTest/compileClasspath': Could not resolve
com.android.support:design:26.1.0.
Error:Unable to resolve dependency
for ':app#debugAndroidTest/compileClasspath': Could not resolve
com.android.support:design:26.1.0.
Error:Unable to resolve dependency
for ':app#debug/compileClasspath': Could not resolve
com.android.support:design:26.1.0.
And only the 'Snackbar' function does not work but rest of it seems fine.
When I change the design to 25.1.0 version instead, it works but it clashes with other 26.1.0 ones so it's not recommended by the Android Studio. Anyone..?
I have tried putting the
compile 'com.android.support:design:26.1.0'
instead of implement, it does not work. When I tried to change the whole thing to either 25.4.0 or any other 25 version, a lot of other things doesnt compile as well. I have unchecked the Offline work, tried removing / adding maven directory, un-commenting a few more of dependencies, changing all to compile instead of implement but just gives me more errors.
Yes I have updated all my SDKs to the newest but I have a feeling that Gradle just cannot download certain dependencies from the websites that's why I cannot download any more of the other dependencies. (Although my off-line work is unchecked)
Also, whatever that are uncommented in the code above, it means I have tried inputting those lines but it did not solve the issue or rather created more issues.

Answer 1

Here is the way i found it please try the below
Go to File->Settings->Build, Execution, Deployment->Gradle->Uncheck Offline work option.

Answer 2

Try this once ,instead of implementing compile the design support gradle code
compile 'com.android.support:design:26.1.0'
and remove this
implementation 'com.android.support:design:26.1.0'

Answer 3

Problem that I realized in the end was that when I was setting up the android proxy, I have only set up 1 proxy which was for HTTP and did not realize that HTTPS proxy was not set up.
So after fixing that issue by setting HTTPS proxy, there was no more problems.