Problems not seeing Android xml layout (Gradle build problem)

https://mplatform.seoul.go.kr/w/contest/award/2016/wnpz/selectPageListWinner.do

I didn't know how to play Android, so I tried to open an open source and study, but it worked, but the layout preview didn't come up properly. So I was googling to solve it, but I ended up asking a question because I got a bigger error.

1) When I opened the open source, I couldn't see the layout preview.

2) So when I googled the error message, I saw a stack overflow post, and I knew that Gradle was wrong, but I couldn't apply it because the gradle code shown there was different from my gradle code. (I tried copying and pasting the answers, but they didn't work)

3) There was a red line on my Gradle code, and I googled it with that error code. ( compile 'com.android.support:appcompat-v7:23.4.0' )

The code for that red line is as follows. build.gradle (Module: app)

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'

android {
    compileSdkVersion 23
    buildToolsVersion '26.0.2'

    defaultConfig {
        applicationId "com.runfive.hangangrunner"
        minSdkVersion 19
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
        multiDexEnabled true
    }

    dexOptions {
        jumboMode true
        javaMaxHeapSize "2g"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
repositories {
    mavenCentral()
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.4.0'
    compile 'com.android.support:support-v4:23.4.0'
    compile 'com.android.support:design:23.4.0'
    //compile 'com.naver.maps.open:naver-map-api:2.1.2@aar'Change to Google Maps
    compile project(':decoviewlib')
    compile project(':calendarlib')
    compile 'com.google.android.gms:play-services:9.0.2'
    compile 'com.google.android.gms:play-services:7.5.+'
    //compile 'com.google.android.gms:play-services-maps:9.4.0'
    //compile 'com.google.android.gms:play-services:9.4.0'
    compile 'com.google.maps.android:android-maps-utils:0.4'
    compile 'com.squareup.okhttp:okhttp:2.7.2'
    compile 'com.google.code.gson:gson:2.6.2'
    // Written by daily fragment

    // Facebook link
    compile 'com.facebook.android:facebook-android-sdk:4.6.0'

    // Naver login link
    compile files('libs/3rdparty_login_library_android_4.1.4.jar')

    // Card View
    compile 'com.android.support:recyclerview-v7:23.4.0'
    compile 'com.android.support:cardview-v7:23.4.0'

    // Font
    compile 'com.tsengvn:Typekit:1.0.0'

    // Subversion Support
    compile 'com.android.support:multidex:1.0.0'
}

I searched the red line first. However, even if I tried copying and pasting the answer, the error could not be solved.

https://stackoverflow.com/questions/39188699/failed-to-resolve-com-android-supportappcompat-v723-4-0

So I googled the error code below.

I googled and found a tea story blog.

According to the blog, "In Android Studio 3.1.0 and later versions, these build errors appear in existing projects, so add the code below."

http://dwfox.tistory.com/73

So I added those three lines to the code as the blog told me to.

    // Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
        google()
    }
   dependencies {
       classpath 'com.android.tools.build:gradle:3.0.1'
       classpath 'com.android.tools.build:gradle:1.3.0-beta1'
       classpath 'com.google.gms:google-services:1.3.0-beta1'

       compile 'com.android.support:appcompat-v7:25.3.0' //Google Component
       compile 'com.android.support:customtabs:25.3.0'
       compile 'com.android.support:mediarouter-v7:25.3.0'

      // // 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
}

Then, this time, a new error appeared.

Please install the Android Support Repository from the Android SDK Manager.

When I googled and pasted the answers to solve the problem, a new error appears again...

I'm repeating this like an infinite loop. How do we solve this?

android xml layout gradle build

2022-09-21 21:37