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Constraint Layout Vertical Align Center

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How do I center align a view in constraint layout?

Center a view horizontally, set layout_constraintLeft_toLeftOf and layout_constraintRight_toRightOf to parent. Center a view vertically, set layout_constraintTop_toTopOf and layout_constraintBottom_toBottomOf to parent. Align to the top left.

What is vertical bias in constraint layout?

Bias, in terms of ConstraintLayout , means "if there is extra room, slide the widget in this direction along the axis". The default bias is 0.5, meaning that the widget is centered in the available space.

How do I center an image in constraint layout in Android Studio?

You can use layout_constraintCircle for center view inside ConstraintLayout .


It's possible to set the center aligned view as an anchor for other views. In the example below "@+id/stat_2" centered horizontally in parent and it serves as an anchor for other views in this layout.

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/stat_1"
        android:layout_width="80dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:gravity="center"
        android:maxLines="1"
        android:text="10"
        android:textColor="#777"
        android:textSize="22sp"
        app:layout_constraintTop_toTopOf="@+id/stat_2"
        app:layout_constraintEnd_toStartOf="@+id/divider_1" />

    <TextView
        android:id="@+id/stat_detail_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Streak"
        android:textColor="#777"
        android:textSize="12sp"
        app:layout_constraintTop_toBottomOf="@+id/stat_1"
        app:layout_constraintStart_toStartOf="@+id/stat_1"
        app:layout_constraintEnd_toEndOf="@+id/stat_1" />

    <View
        android:id="@+id/divider_1"
        android:layout_width="1dp"
        android:layout_height="0dp"
        android:layout_marginEnd="16dp"
        android:background="#ccc"
        app:layout_constraintTop_toTopOf="@+id/stat_2"
        app:layout_constraintEnd_toStartOf="@+id/stat_2"
        app:layout_constraintBottom_toBottomOf="@+id/stat_detail_2" />

    <TextView
        android:id="@+id/stat_2"
        android:layout_width="80dp"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:maxLines="1"
        android:text="243"
        android:textColor="#777"
        android:textSize="22sp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintBottom_toBottomOf="parent" />

    <TextView
        android:id="@+id/stat_detail_2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:maxLines="1"
        android:text="Calories Burned"
        android:textColor="#777"
        android:textSize="12sp"
        app:layout_constraintTop_toBottomOf="@+id/stat_2"
        app:layout_constraintStart_toStartOf="@+id/stat_2"
        app:layout_constraintEnd_toEndOf="@+id/stat_2" />

    <View
        android:id="@+id/divider_2"
        android:layout_width="1dp"
        android:layout_height="0dp"
        android:layout_marginStart="16dp"
        android:background="#ccc"
        app:layout_constraintBottom_toBottomOf="@+id/stat_detail_2"
        app:layout_constraintStart_toEndOf="@+id/stat_2"
        app:layout_constraintTop_toTopOf="@+id/stat_2" />

    <TextView
        android:id="@+id/stat_3"
        android:layout_width="80dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:gravity="center"
        android:maxLines="1"
        android:text="3200"
        android:textColor="#777"
        android:textSize="22sp"
        app:layout_constraintTop_toTopOf="@+id/stat_2"
        app:layout_constraintStart_toEndOf="@+id/divider_2" />

    <TextView
        android:id="@+id/stat_detail_3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:maxLines="1"
        android:text="Steps"
        android:textColor="#777"
        android:textSize="12sp"
        app:layout_constraintTop_toBottomOf="@+id/stat_3"
        app:layout_constraintStart_toStartOf="@+id/stat_3"
        app:layout_constraintEnd_toEndOf="@+id/stat_3" />

</android.support.constraint.ConstraintLayout>

Here's how it works on smallest smartphone (3.7 480x800 Nexus One) vs largest smartphone (5.5 1440x2560 Pixel XL)

Result view


If you have a ConstraintLayout with some size, and a child View with some smaller size, you can achieve centering by constraining the child's two edges to the same two edges of the parent. That is, you can write:

app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"

or

app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"

Because the view is smaller, these constraints are impossible. But ConstraintLayout will do the best it can, and each constraint will "pull" at the child view equally, thereby centering it.

This concept works with any target view, not just the parent.

Update

Below is XML that achieves your desired UI with no nesting of views and no Guidelines (though guidelines are not inherently evil).

<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#eee">

    <TextView
        android:id="@+id/title1"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginBottom="12dp"
        android:gravity="center"
        android:textColor="#777"
        android:textSize="22sp"
        android:text="10"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toLeftOf="@+id/divider1"
        app:layout_constraintBottom_toBottomOf="parent"/>

    <TextView
        android:id="@+id/label1"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:textColor="#777"
        android:textSize="12sp"
        android:text="Streak"
        app:layout_constraintTop_toBottomOf="@+id/title1"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toLeftOf="@+id/divider1"/>

    <View
        android:id="@+id/divider1"
        android:layout_width="1dp"
        android:layout_height="55dp"
        android:layout_marginTop="12dp"
        android:layout_marginBottom="12dp"
        android:background="#ccc"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toRightOf="@+id/title1"
        app:layout_constraintRight_toLeftOf="@+id/title2"
        app:layout_constraintBottom_toBottomOf="parent"/>

    <TextView
        android:id="@+id/title2"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginBottom="12dp"
        android:gravity="center"
        android:textColor="#777"
        android:textSize="22sp"
        android:text="243"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toRightOf="@+id/divider1"
        app:layout_constraintRight_toLeftOf="@+id/divider2"
        app:layout_constraintBottom_toBottomOf="parent"/>

    <TextView
        android:id="@+id/label2"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:textColor="#777"
        android:textSize="12sp"
        android:text="Calories Burned"
        app:layout_constraintTop_toBottomOf="@+id/title2"
        app:layout_constraintLeft_toRightOf="@+id/divider1"
        app:layout_constraintRight_toLeftOf="@+id/divider2"/>

    <View
        android:id="@+id/divider2"
        android:layout_width="1dp"
        android:layout_height="55dp"
        android:layout_marginTop="12dp"
        android:layout_marginBottom="12dp"
        android:background="#ccc"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toRightOf="@+id/title2"
        app:layout_constraintRight_toLeftOf="@+id/title3"
        app:layout_constraintBottom_toBottomOf="parent"/>

    <TextView
        android:id="@+id/title3"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginBottom="12dp"
        android:gravity="center"
        android:textColor="#777"
        android:textSize="22sp"
        android:text="3200"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toRightOf="@+id/divider2"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"/>

    <TextView
        android:id="@+id/label3"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:textColor="#777"
        android:textSize="12sp"
        android:text="Steps"
        app:layout_constraintTop_toBottomOf="@+id/title3"
        app:layout_constraintLeft_toRightOf="@+id/divider2"
        app:layout_constraintRight_toRightOf="parent"/>

</android.support.constraint.ConstraintLayout>

enter image description here


May be i did not fully understand the problem, but, centering all view inside a ConstraintLayout seems very simple. This is what I used:

<android.support.constraint.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:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center">

enter image description here

Last two lines did the trick!


 <TextView
        android:id="@+id/tvName"
        style="@style/textViewBoldLarge"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="Welcome"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"/>

You can easily center multiple things by creating a chain. It works both vertically and horizontally

Link to official documentation about chains

Edit to answer comment :

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
    <TextView
        android:id="@+id/first_score"
        android:layout_width="60dp"
        android:layout_height="wrap_content"
        android:text="10"
        app:layout_constraintEnd_toStartOf="@+id/second_score"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/second_score"
        app:layout_constraintBottom_toTopOf="@+id/subtitle"
        app:layout_constraintHorizontal_chainStyle="spread"
        app:layout_constraintVertical_chainStyle="packed"
        android:gravity="center"
        />
    <TextView
        android:id="@+id/subtitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Subtitle"
        app:layout_constraintTop_toBottomOf="@+id/first_score"
        app:layout_constraintBottom_toBottomOf="@+id/second_score"
        app:layout_constraintStart_toStartOf="@id/first_score"
        app:layout_constraintEnd_toEndOf="@id/first_score"
        />
    <TextView
        android:id="@+id/second_score"
        android:layout_width="60dp"
        android:layout_height="120sp"
        android:text="243"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/thrid_score"
        app:layout_constraintStart_toEndOf="@id/first_score"
        app:layout_constraintTop_toTopOf="parent"
        android:gravity="center"
        />
    <TextView
        android:id="@+id/thrid_score"
        android:layout_width="60dp"
        android:layout_height="wrap_content"
        android:text="3200"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@id/second_score"
        app:layout_constraintTop_toTopOf="@id/second_score"
        app:layout_constraintBottom_toBottomOf="@id/second_score"
        android:gravity="center"
        />
</android.support.constraint.ConstraintLayout>

This code gives this result

You have the horizontal chain : first_score <=> second_score <=> third_score. second_score is centered vertically. The other scores are centered vertically according to it.

You can definitely create a vertical chain first_score <=> subtitle and center it according to second_score