Develop Reference

Android. ConstraintLayout: constraint end not working

I need to create chain with ConstraintLayout.I want the TextView to be attached to the left side, the text is immediately followed by a ImageView, and another ImageView is attached to the right side of the screen. See an example.
If the TextView contains long text, I need the text to go to another line. That is, so that the TextView does not overlap with the image view on the right, but is limited to margin. See an example.
Here is my code:
<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:layout_width="match_parent"
android:layout_height="wrap_content"
tools:ignore="MissingPrefix">
<TextView
android:id="#+id/tvTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/text"
android:textColor="#color/black"
android:textSize="#dimen/text_size_14"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0" />
<ImageView
android:id="#+id/ivFirst"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="16dp"
android:src="#drawable/ic_first"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#id/ivSecond"
app:layout_constraintHorizontal_bias="0"
app:layout_constraintStart_toEndOf="#id/tvTitle"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0" />
<ImageView
android:id="#+id/ivSecond"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_second"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0" />
</androidx.constraintlayout.widget.ConstraintLayout>
If the text is not long, then everything works well, but if the text is long, then it is superimposed on the ImageView and goes beyond the screen. I tried to use chain but nothing worked. Please, help me.

You can achieve this by fixing ivSecond to the end of the parent and then creating a horizontal chain of tvTitle and ivFirst, so long as you apply a packed chain style and a bias of 0 to the chain and use constrainedWidth on the text view.
<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:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="#+id/tvTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constrainedWidth="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#id/ivFirst"
app:layout_constraintHorizontal_bias="0"
app:layout_constraintHorizontal_chainStyle="packed"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:text="hello world"/>
<ImageView
android:id="#+id/ivFirst"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#id/ivSecond"
app:layout_constraintStart_toEndOf="#id/tvTitle"
app:layout_constraintTop_toTopOf="parent"/>
<ImageView
android:id="#+id/ivSecond"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>
When the text is short, the first image is right up against it:
When the text is long, the first image stops at the edge of the second image and the text wraps to another line:

you can do it with layout_constrainedWidth . For this your text view needs to be constrained horizontally . try the layout below i have made few changes in it .
<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:layout_width="match_parent"
android:layout_height="wrap_content"
tools:ignore="MissingPrefix">
<TextView
android:id="#+id/tvTitle"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textSize="14sp"
app:layout_constrainedWidth="true"
app:layout_constraintEnd_toStartOf="#+id/ivFirst"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0" />
<ImageView
android:id="#+id/ivFirst"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="16dp"
android:src="#mipmap/ic_launcher"
app:layout_constraintEnd_toStartOf="#id/ivSecond"
app:layout_constraintStart_toEndOf="#id/tvTitle"
app:layout_constraintTop_toTopOf="parent"
/>
<ImageView
android:id="#+id/ivSecond"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#mipmap/ic_launcher"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
/>
</androidx.constraintlayout.widget.ConstraintLayout>

You can use FlexboxLayout to wrap the tvTitle TextView & the ivFirst ImageView; So that it controls to wrap the content of the TextView to the next line and avoid pushing the ivFirst to the right/end.
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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">
<com.google.android.flexbox.FlexboxLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:orientation="horizontal"
app:alignContent="center"
app:alignItems="center"
app:flexDirection="row"
app:flexWrap="nowrap"
app:layout_constraintBottom_toBottomOf="#+id/ivSecond"
app:layout_constraintEnd_toStartOf="#+id/ivSecond"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:id="#+id/tvTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/text"
android:textColor="#color/black"
android:textSize="#dimen/text_size_14"
app:layout_flexShrink="10000" />
<ImageView
android:id="#+id/ivFirst"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_first"
android:layout_marginStart="8dp"
android:layout_marginEnd="16dp"/>
</com.google.android.flexbox.FlexboxLayout>
<ImageView
android:id="#+id/ivSecond"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_second"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Also make sure to add the gradle dependency at module level:
implementation 'com.google.android.flexbox:flexbox:3.0.0'
Preview:

Alignment/wrapping inside the ConstraintLayout

I have 3 text views placed horizontally. Leftmost one and rightmost one are of fixed size, but middle one can vary in length significantly. Something like this:
<?xml version="1.0" encoding="utf-8"?>
<layout 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">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp">
<TextView
android:id="#+id/left"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingEnd="8dp"
android:text="LEFT"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/message"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:paddingEnd="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/right"
app:layout_constraintStart_toEndOf="#+id/left"
app:layout_constraintTop_toTopOf="parent"
tools:text="#tools:sample/lorem/random" />
<TextView
android:id="#+id/right"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="RIGHT"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/message"
app:layout_constraintTop_toTopOf="parent"
tools:visibility="visible" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
This results in following layout:
But if we have short text in the middle, like this:
tools:text="#tools:sample/lorem"
it will look:
Rightmost view is "glued" to the end.
I want it to follow the middle view, like this:
How can it be achieved?

You should use app:layout_constraintWidth_default="wrap" for the middle view and app:layout_constraintHorizontal_chainStyle="packed". Also don't forget to set app:layout_constraintHorizontal_bias="0.0" for the first view to align the whole layout to the start of the screen. Here how the whole layout should look:
<?xml version="1.0" encoding="utf-8"?>
<layout 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">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp">
<TextView
android:id="#+id/left"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="8dp"
android:text="LEFT"
app:layout_constraintEnd_toStartOf="#id/message"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintHorizontal_chainStyle="packed"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/message"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:padding="8dp"
app:layout_constraintEnd_toStartOf="#id/apply_text"
app:layout_constraintStart_toEndOf="#id/left"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintWidth_default="wrap"
tools:text="#tools:sample/lorem" />
<TextView
android:id="#+id/apply_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="8dp"
android:text="RIGHT"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#id/message"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Here is the result:

It is quite a challenge. AFAIK, To do what you want, you have to change the width of the middle TextView to wrap_content and remove right TextView constraint with parent's right.
You could try something like calculating width of left and right then if the total width of the device is more than or equal left + right + middle then you switch from
to this

Android Constraint layout, views with weight?

So like the picture below, I want view B be twice the length of view A.
What I exactly need is view A sticks to the left edge, view B sticks to the right edge and they stick to each other in between. And in the length, the B is going to be twice the length of A. I tried a lot, but no luck! in the end, something is not what I want. Either there is unwanted space between a view and its according edge or between the two views.
Here is my last try:
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp"
tools:context=".MainActivity">
<EditText
android:id="#+id/editText"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_marginTop="36dp"
android:ems="10"
android:text="B"
android:inputType="textPersonName"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_weight="2"
app:layout_constraintStart_toEndOf="#+id/textView"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_marginTop="36dp"
android:gravity="center"
android:text="A"
app:layout_constraintHorizontal_weight="1"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

You can use app:layout_constraintWidth_percent ti tell your view how to spread on the screen.
For your wanted look you can use it like this:
<?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">
<Button
android:id="#+id/button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Button"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/button2"
app:layout_constraintWidth_percent=".33"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/button2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Button"
app:layout_constraintBottom_toBottomOf="#+id/button"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintWidth_percent=".66"
app:layout_constraintStart_toEndOf="#+id/button"
app:layout_constraintTop_toTopOf="#+id/button" />
</android.support.constraint.ConstraintLayout>
It will look like this

To use layout_constraintHorizontal_weight, you have to put your Views in a chain first. That means you have to constraint both Views to each other and the parent horizontally. What you are missing in your case is the app:layout_constraintEnd_toStartOf="#id/editText" on the TextView. You also need to change the android:layout_width of both Views to 0dp so that the weight is enforced:
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp"
tools:context=".MainActivity">
<EditText
android:id="#+id/editText"
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_marginTop="36dp"
android:ems="10"
android:text="B"
android:inputType="textPersonName"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_weight="2"
app:layout_constraintStart_toEndOf="#+id/textView"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/textView"
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_marginTop="36dp"
android:gravity="center"
android:text="A"
app:layout_constraintHorizontal_weight="1"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toStartOf="#id/editText"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

ConstraintLayout align text right in TextView

How to align text in TextView when it is inside ConstraintLayout? I cannot use layout_width="match_parent. Tried this, does not work :(
android:gravity="start"
android:textAlignment="gravity"

Make the TextView match parent with:
android:layout_width="0dp"
Then define the textAlignment property:
android:textAlignment="viewEnd"
Example, align right in a left to right language:
<TextView
android:id="#+id/tv_item"
style="#style/text_highlight_small_title"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="#string/my_text"
android:textAlignment="viewStart"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:text="Sample Text" />
Note you can use different values for textAlignment as defined in the documentation.

Unfortunately, we are missing the whole XML of your layout, but let's assume you have something like this:
<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:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Something Important to align"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
Now if you create exactly this layout, TextView is gonna be in the center. This is the default behavior of the ConstraintLayout, it always tries to center views in it if you set constraints this way. This behavior can be influenced by app:layout_constraintHorizontal_bias and app:layout_constraintVertical_bias property of the TextView. Default values for both are 0.5 what you can translate to 50%. If you set them both to 0, you will find the TextView in the top left position. If you set them both to 1, the TextView will end up in the bottom right position. You got the idea, this way you can position your TextView or any View wherever you want.
The bias properties are also described in the official documentation here.
Fully working example of TextView aligned to center vertically and aligned to right horizontally:
<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:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Something Important to align"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.5" />
</android.support.constraint.ConstraintLayout>

Solution:
use this xml code
<?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:text="TextView"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:id="#+id/textView"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginLeft="16dp"
android:layout_marginEnd="16dp"
android:gravity="start"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginRight="16dp" />
</android.support.constraint.ConstraintLayout>
Hope it helps.

use this xml code
<?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:text="TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/textView"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginLeft="16dp"
android:layout_marginEnd="16dp"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginRight="16dp" />
</android.support.constraint.ConstraintLayout>

In general, if you have more then one TextView in a single line it is not trivial to align the first TextView to the left. I have used a Guideline for this pourpose and it works perfectly. If you remove the GuideLine it doesn't works.
Here is the xml:
<TextView
android:id="#+id/textView1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="130dp"
android:ellipsize="end"
android:maxLines="1"
android:text="first very long very long long long long long very long text"
android:textAlignment="viewStart"
app:layout_constraintEnd_toStartOf="#id/textView2"
app:layout_constraintStart_toStartOf="#+id/guideline"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="130dp"
android:text="second text"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<android.support.constraint.Guideline
android:id="#+id/guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_begin="0dp" />

Try this:
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/textView"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:gravity="right"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginLeft="16dp"
android:layout_marginEnd="16dp"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginRight="16dp" />

Try this:
<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="match_parent"
tools:context="com.example.YOURUSER.YOURPROJECT.YOURACTIVITY">
<TextView
android:id="#+id/TextView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" />

Use design because it is much easier than xml video file

Android Setup constraint for view2 to follow start of view1. But view1 has constraint to start of its parent

I cannot achieve this one.
I want viewB to follow the start of viewA.
Then I want to create a constraint to have a space from the start of viewA to its parent.
.
Code I tried:
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="10dp">
<TextView
android:id="#+id/descriptionTxt"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginEnd="32dp"
android:layout_marginStart="8dp"
android:text="Txt1"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/descriptionTxt2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="Txt2"
app:layout_constraintEnd_toEndOf="#+id/descriptionTxt"
app:layout_constraintStart_toStartOf="#+id/descriptionTxt"
app:layout_constraintTop_toBottomOf="#+id/descriptionTxt" />
</android.support.constraint.ConstraintLayout>
The code above will show in Preview that only viewA will have a margin from the left. viewB does not follow the left of viewA.
Im using com.android.support.constraint:constraint-layout:1.0.2

Do not use match_parent. Instead, start using "0dp" for match_parent and define left/right or top/bottom parent constraints
Here is working code:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_margin="10dp"
xmlns:android="http://schemas.android.com/apk/res/android">
<TextView
android:id="#+id/descriptionTxt"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginEnd="32dp"
android:layout_marginStart="8dp"
android:text="Txt1"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/descriptionTxt2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="Txt2"
app:layout_constraintEnd_toEndOf="#+id/descriptionTxt"
app:layout_constraintStart_toStartOf="#+id/descriptionTxt"
app:layout_constraintTop_toBottomOf="#+id/descriptionTxt" />
</android.support.constraint.ConstraintLayout>
Also , it is good to use Guidelines to have uniform left/top/right/bottom margin.

try this :
<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">
<TextView
android:id="#+id/descriptionTxt"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Txt1"
android:layout_marginTop="20dp"
android:layout_marginLeft="20dp"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
/>
<TextView
android:id="#+id/descriptionTxt2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Txt2"
android:layout_marginTop="8dp"
app:layout_constraintRight_toRightOf="#+id/descriptionTxt"
app:layout_constraintLeft_toLeftOf="#+id/descriptionTxt"
app:layout_constraintTop_toBottomOf="#+id/descriptionTxt"
/>
</android.support.constraint.ConstraintLayout>