There are errors in com.android.support:appcompat-v7:28.0.0 what should I do?

Question

android studio

until now everything was working fine. application compiled. even put it on google play.
What have I done wrong? in builde.gradle underlines in red implementation ' com.android.support:appcompat-v7:28.0.0 '
when compiling, an error occurs like this:

Duplicate class android.support.v4.app.INotificationSideChannel found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android .support.v4.app.INotificationSideChannel$Stub found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android. support.v4.app.INotificationSideChannel$Stub$Proxy found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android .support.v4.graphics.drawable.IconCompatParcelizer found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android.support.v4.os.IResultReceiver found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android .support.v4.os.IResultReceiver$Stub found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android. support.v4.os.IResultReceiver$Stub$Proxy found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android .support.v4.os.ResultReceiver found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android.support.v4.os.ResultReceiver$1 found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android.support.v4.os.ResultReceiver$MyResultReceiver found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class android .support.v4.os.ResultReceiver$MyRunnable found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class androidx. core.graphics.drawable.IconCompatParcelizer found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class androidx.core.internal.package-info found in modules classes.jar (androidx.core:core:1.0.0) and classes.jar (com.android.support:support-compat:28.0.0)
Duplicate class androidx
.versionedparcelable.CustomVersionedParcelable found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0) jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.ParcelField found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.ParcelImpl found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.ParcelImpl$1 found in modules classes.jar (androidx.versionedparcelable :versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.ParcelUtils found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcel found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcel$1 found in modules classes.jar (androidx.versionedparcelable :versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcel$ParcelException found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcelParcel found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcelStream found in modules classes.jar (androidx. versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcelStream$FieldBuffer found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcelStream $
InputBuffer found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0) androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Duplicate class androidx.versionedparcelable.VersionedParcelize found in modules classes.jar (androidx.versionedparcelable:versionedparcelable:1.0.0) and classes.jar (com.android.support:versionedparcelable:28.0.0)
Go to the documentation to learn how to Fix dependency resolution errors.

Build.gradle itself:

apply plugin: 'com.android.application'
android {
compileSdkVersion 28
defaultConfig {
applicationId "xxxxxxxxxxxxxxxxxxxxxxx"
minSdkVersion 16
targetSdkVersion 28
versionCode 3
versionName "1.0.3"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
sourceSets { main { assets.srcDirs = ['src/main/assets', 'src/main/assets/'] } }
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support.constraint:constraint-layout :1.0.2'
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'
implementation 'com.google.firebase:firebase-iid:19.0.1'
implementation 'com.google.firebase:firebase-ads:18.1.1'
implementation 'androidx.cardview:cardview:1.0.0'
implementation 'com.google.code .gson:gson:2.8.5'
implementation 'com.google.android.gms:play-services-ads:18.1.1'
}

Answer 1

I had this. I played with versions of dependencies - it was cured.

Answer 2

Who needs I found a solution to the problem!
The first thing I did was copy all my projects.
second - deleted the current version of android. and cleaned all folders after android studio.
Then I downloaded the new version. installed accordingly.
Created a new project.
I copied my projects into the projects folder.
Opened my project and a new one. copied builde.gradle settings and library list.
and most importantly, in gradle.properties,
you need to enter
android.useAndroidX=true
android.enableJetifier=true
https://developer.android.com/jetpack/androidx/migrate
That is, make the project migrate.
These manipulations helped me.

Answer 3

Here is the code from the tutorial describing the simplest program - We take a number from the input.txt file and write it to output.txt

Program Vvod_Vivod;

  var

    a:longint;

    t:text;

Begin

  assign(t,'input.txt');

  reset(t);

  read(t,a);

  close(t);

<b>ВОТ ЗДЕСЬ ВАШ IF СЧИТАЮЩИЙ КОЛ-ВО РАЗРЕЗОВ</b>

  assign (t,'output.txt');

  rewrite(t);

  write(t,a);

  close(t);

End.