title: Constraint layout has space bottom and top
body: <p>I'm building an app using Constraint layout, but it has extra space bottom and top. I can't find where they come from. I checked maybe ten times from top to bottom all code but there is no margin or padding or anything else for it. </p>
  
  <p><a href="https://i.stack.imgur.com/4CBRD.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/4CBRD.jpg" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/rnA6Q.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/rnA6Q.png" alt="enter image description here"></a></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:tools="http://schemas.android.com/tools"
      android:id="@+id/relativeLayout"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:background="@color/black"
      android:paddingLeft="0dp"
      android:paddingTop="0dp"
      android:paddingRight="0dp"
      android:paddingBottom="0dp"&gt;
  
      &lt;androidx.constraintlayout.widget.ConstraintLayout
          android:id="@+id/Brand"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          app:layout_constraintBottom_toTopOf="@id/guideline"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toTopOf="parent"&gt;
  
          &lt;RelativeLayout
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_gravity="center"
              android:orientation="horizontal"
              app:layout_constraintEnd_toEndOf="parent"
              app:layout_constraintStart_toStartOf="parent"
              app:layout_constraintTop_toTopOf="parent"&gt;
  
              &lt;TextView
                  android:id="@+id/brandname"
                  style="@style/viewParent.headerText"
                  android:text="Did"
                  android:textColor="@color/white" /&gt;
  
              &lt;TextView
                  android:id="@+id/brandname2"
                  style="@style/viewParent.headerText2"
                  android:layout_toRightOf="@id/brandname"
                  android:text="You"
                  android:textColor="@color/yellow" /&gt;
  
              &lt;TextView
                  style="@style/viewParent.headerText2"
                  android:layout_toRightOf="@id/brandname2"
                  android:text="Know!"
                  android:textColor="@color/red"
                  android:textStyle="bold|italic" /&gt;
          &lt;/RelativeLayout&gt;
      &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  
      &lt;androidx.constraintlayout.widget.ConstraintLayout
          android:id="@+id/container_main"
          android:layout_width="0dp"
          android:layout_height="0dp"
          android:layout_margin="4dp"
          android:background="@drawable/card_bg"
          android:paddingLeft="16dp"
          android:paddingRight="16dp"
          app:layout_constraintBottom_toTopOf="@id/guideline2"
          app:layout_constraintEnd_toEndOf="@id/guidelineyazisag"
          app:layout_constraintStart_toStartOf="@id/guidelineyazisol"
          app:layout_constraintTop_toBottomOf="@id/guideline"&gt;
  
          &lt;TextView
              android:id="@+id/activity_main_text_view_id"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_margin="10dp"
              android:text="simple Title Text"
              android:textColor="#5E4C4C"
              android:textStyle="bold"
              app:layout_constraintStart_toStartOf="parent"
              app:layout_constraintTop_toTopOf="parent" /&gt;
  
          &lt;TextView
              android:id="@+id/activity_main_did_u_know"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_margin="10dp"
              android:text="Category"
              android:textColor="#5E4C4C"
              android:textStyle="bold"
              app:layout_constraintEnd_toEndOf="parent"
              app:layout_constraintTop_toTopOf="parent" /&gt;
  
          &lt;androidx.core.widget.NestedScrollView
              android:id="@+id/scrollview"
              android:layout_width="match_parent"
              android:layout_height="0dp"
              android:fillViewport="true"
              app:layout_constraintBottom_toTopOf="@id/activity_main_image_view"
              app:layout_constraintTop_toBottomOf="@id/activity_main_did_u_know"&gt;
  
              &lt;androidx.constraintlayout.widget.ConstraintLayout
                  android:layout_width="match_parent"
                  android:layout_height="0dp"
                  app:layout_constraintBottom_toTopOf="@id/activity_main_image_view"
                  app:layout_constraintTop_toBottomOf="@id/activity_main_did_u_know"&gt;
  
                  &lt;TextView
                      android:id="@+id/factTextView"
                      android:layout_width="match_parent"
                      android:layout_height="match_parent"
                      android:layout_marginTop="8dp"
                      android:gravity="center_vertical|center_horizontal"
                      android:lineSpacingExtra="8dp"
                      android:padding="10dp"
                      android:text="Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged."
                      android:textColor="#000000"
                      android:textSize="16dp"
                      app:layout_constraintBottom_toBottomOf="parent"
                      app:layout_constraintEnd_toEndOf="parent"
                      app:layout_constraintHorizontal_bias="1.0"
                      app:layout_constraintStart_toStartOf="parent"
                      app:layout_constraintTop_toTopOf="parent"
                      app:layout_constraintVertical_bias="0.0" /&gt;
  
              &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  
          &lt;/androidx.core.widget.NestedScrollView&gt;
  
          &lt;ImageView
              android:id="@+id/activity_main_image_view"
              android:layout_width="30dp"
              android:layout_height="40dp"
              android:layout_marginStart="16dp"
              android:layout_marginLeft="16dp"
              android:clickable="true"
              android:src="@drawable/ic_share_black_24dp"
              app:layout_constraintBottom_toBottomOf="parent"
              app:layout_constraintStart_toStartOf="parent"
              app:layout_constraintTop_toBottomOf="@id/scrollview" /&gt;
  
          &lt;ImageView
              android:id="@+id/activity_main_fav_button"
              android:layout_width="30dp"
              android:layout_height="40dp"
              android:layout_margin="16dp"
              android:clickable="true"
              android:src="@drawable/ic_favorite_border_black_24dp"
              app:layout_constraintBottom_toBottomOf="parent"
              app:layout_constraintEnd_toEndOf="parent"
              app:layout_constraintTop_toBottomOf="@id/scrollview" /&gt;
  
      &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  
      &lt;androidx.constraintlayout.widget.ConstraintLayout
          android:id="@+id/LeftRight"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          app:layout_constraintBottom_toTopOf="@id/adView"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toBottomOf="@+id/guideline2"&gt;
  
          &lt;ImageView
              android:id="@+id/activity_main_left_button"
              android:layout_width="60dp"
              android:layout_height="60dp"
              android:clickable="true"
              android:src="@drawable/ic_previous"
              android:elevation="3dp"
              android:background="@drawable/okarka"
              app:layout_constraintBottom_toBottomOf="parent"
              app:layout_constraintEnd_toStartOf="@id/guideline3"
              app:layout_constraintStart_toStartOf="parent"
              app:layout_constraintTop_toTopOf="parent" /&gt;
  
          &lt;ImageView
              android:id="@+id/activity_main_right_button"
              android:layout_width="60dp"
              android:layout_height="60dp"
              android:clickable="true"
              android:src="@drawable/ic_next"
              app:layout_constraintBottom_toBottomOf="parent"
              app:layout_constraintEnd_toEndOf="parent"
              app:layout_constraintHorizontal_bias="0.5"
              android:background="@drawable/okarka"
              app:layout_constraintStart_toEndOf="@+id/guideline3"
              app:layout_constraintTop_toTopOf="parent" /&gt;
  
          &lt;androidx.constraintlayout.widget.Guideline
              android:id="@+id/guideline3"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:orientation="vertical"
              app:layout_constraintGuide_percent="0.5" /&gt;
      &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  
      &lt;com.google.android.gms.ads.AdView xmlns:ads="http://schemas.android.com/apk/res-auto"
          android:id="@+id/adView"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_centerHorizontal="true"
          ads:adSize="SMART_BANNER"
          ads:adUnitId="ca-app-pub-3940256099942544/6300978111"
          ads:layout_constraintBottom_toBottomOf="parent"
          ads:layout_constraintLeft_toLeftOf="parent"
          ads:layout_constraintRight_toRightOf="parent"
          app:layout_constraintTop_toBottomOf="@id/LeftRight" /&gt;
  
      &lt;androidx.constraintlayout.widget.Guideline
          android:id="@+id/guideline"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:orientation="horizontal"
          app:layout_constraintGuide_percent="0.076" /&gt;
  
      &lt;androidx.constraintlayout.widget.Guideline
          android:id="@+id/guideline2"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:orientation="horizontal"
          app:layout_constraintGuide_percent="0.7" /&gt;
  
      &lt;androidx.constraintlayout.widget.Guideline
          android:id="@+id/guidelineyazisol"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:orientation="vertical"
          app:layout_constraintGuide_percent="0.07" /&gt;
  
      &lt;androidx.constraintlayout.widget.Guideline
          android:id="@+id/guidelineyazisag"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:orientation="vertical"
          app:layout_constraintGuide_percent="0.93" /&gt;
  &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  </code></pre>
  
  <p>I tried adding guidelines to 0 points in the bottom but it also starts in that space. I gave -(minus) values to margin and padding but doesn't work. I don't know what else to do. You can see from screenshots how it looks. </p>
  
  <pre><code>public class MainActivity extends AppCompatActivity {
  
      private ColorWheel colorWheel = new ColorWheel();
      private TextView factTextView;
      private TextView textViewId;
      private TextView textViewTableName;
      ImageView tableImageView;
      AdView adView;
      ImageView shareImageView;
      ImageView favImageView;
      float x1,x2,y1,y2;
      int i = 1;
      int adCounter = 0;
      private ConstraintLayout constraintLayout;
      String fact;
      ArrayList&lt;Fact&gt; favList = new ArrayList&lt;&gt;();
      private InterstitialAd mInterstitial;
      AdRequest interAdRequest;
      int favId;
      String favTable;
      Typeface typeface;
      List&lt;Fact&gt; mData;
      private DatabaseFacts db;
      GradientDrawable shape;
  
      @SuppressLint({"ClickableViewAccessibility", "SetTextI18n"})
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
          db = new DatabaseFacts(this);
          db.copyDbIfNotExists();
          shape =  new GradientDrawable();
          shape.setCornerRadius(40);
          mData = new ArrayList&lt;&gt;();
          MobileAds.initialize(this, "ca-app-pub-2469721886989416~7390658870");
          adView = findViewById(R.id.adView);
          AdRequest bannerAdRequest = new AdRequest.Builder().build();
          adView.loadAd(bannerAdRequest);
  
          interAdRequest = new AdRequest.Builder().build();
          mInterstitial = new InterstitialAd(this);
          mInterstitial.setAdUnitId("ca-app-pub-2469721886989416/9441000894");
          mInterstitial.loadAd(interAdRequest);
  
          factTextView = findViewById(R.id.factTextView);
          constraintLayout = (ConstraintLayout) findViewById(R.id.container_main);
          textViewId = findViewById(R.id.activity_main_text_view_id);
          favImageView = findViewById(R.id.activity_main_fav_button);
          shareImageView = findViewById(R.id.activity_main_image_view);
          textViewTableName = findViewById(R.id.activity_main_did_u_know);
  //        tableImageView = findViewById(R.id.img_user);
  //        if (android.os.Build.VERSION.SDK_INT &gt;= android.os.Build.VERSION_CODES.O) {
  //            typeface = getResources().getFont(R.font.sourceserifproregular);
  //        }
          factTextView.setTypeface(typeface);
          Intent intent  = getIntent();
          final int choice = intent.getIntExtra("choice",0);
  
          switch (choice) {
              case 1:
  
                  textViewTableName.setText("General Facts");
                  factTextView.setText(db.getFact((readFromShared("defaultKey") - 1), DatabaseFacts.TABLE_GENERAL_NAME).getFact());
                  textViewId.setText("Fact " + (readFromShared("defaultKey") - 1) + " of " + db.getFactsCount(DatabaseFacts.TABLE_GENERAL_NAME));
  
                  if (db.getFact((readFromShared("defaultKey") - 1), DatabaseFacts.TABLE_GENERAL_NAME).isFavorite() == 0) {
                      favImageView.setImageResource(R.drawable.ic_favorite_border_black_24dp);
                  } else {
                      favImageView.setImageResource(R.drawable.ic_favorite_black_24dp);
                  }
  
                  ImageView leftClick = (ImageView) findViewById(R.id.activity_main_left_button);
                  leftClick.setOnClickListener(new View.OnClickListener() {
                      @Override
                      public void onClick(View v) {
                          leftClickMethod("defaultKey", DatabaseFacts.TABLE_GENERAL_NAME);
  
                      }
                  });
  
                  ImageView rightClick = (ImageView) findViewById(R.id.activity_main_right_button);
                  rightClick.setOnClickListener(new View.OnClickListener() {
                      @Override
                      public void onClick(View v) {
                          rightClickMethod("defaultKey",DatabaseFacts.TABLE_GENERAL_NAME);
                          return;
                      }
                  });
  
                  favImageView.setOnClickListener(v -&gt; handleFavorites("defaultKey", DatabaseFacts.TABLE_GENERAL_NAME));
                  break;
  </code></pre>