View goes out of screen with ConstraintLayout Kotlin

Question

I need to build UI with two TextViews which are constrained first top parent, and second is constrained below first TextView. The problem comes when text_one has more text and bring text_two outside the screen. The desired behavior is when text_one has more text text_two to be aligned bottom to parent and to don't go outside the screen. Something like weight 9:1 but this needs to be achieved only when text_one has more text. Normal behavior is represented in screen1 the problem is shown in screen2.

    <?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"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/txt_one"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:background="#FF00"
        android:text="the majority have suffered alteration in some form etc..."
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/txt_two"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:background="@color/colorPrimary"
        android:text="It is a long established etc......"
        app:layout_constraintTop_toBottomOf="@+id/txt_one"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent" />


</androidx.constraintlayout.widget.ConstraintLayout>

Answer 1

try the following sample it's maintain the other textView height even if first one take larger space on the screen

<?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="match_parent">

<TextView
    android:id="@+id/txt_one"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:background="#FF00"
    android:textSize="35sp"
    android:text="the majority
     e suffered alteration in some form etc..."
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintVertical_bias="0.0"
    app:layout_constrainedHeight="true"
    app:layout_constraintVertical_chainStyle="packed"
    app:layout_constraintTop_toTopOf="parent"
    app:layout_constraintBottom_toTopOf="@id/txt_two"
    />

<TextView
    android:id="@+id/txt_two"
    android:layout_width="0dp"
    app:layout_constraintBottom_toBottomOf="parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:textSize="25sp"
    android:background="@color/colorPrimary"
    android:text="It is a long etc......"
    app:layout_constraintTop_toBottomOf="@+id/txt_one"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintEnd_toEndOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

Answer 2

You can make use of

 app:layout_constraintHeight_max 

property of constraint layout.

For programmatically use

setMaxHeight()

In your use case, while screen rendering get screen height,

val text1MaxHeight = screenHeight*0.9
text1.setMaxHeight(text1MaxHeight)

It should work.

But If your textview1 will have more content, you would want it scrollable, so a new solution would suggest you to Encapsulate textview1 in scrollView, and take scrollview and textview2 in NestedScrollView like below

<NestedScrollView>
    <ScrollView>
      <TextView1/>
    <ScrollView/>
    <TextView2/>
<NestedScrollView>

Make nestedScrollingEnabled flag false in ScrollView, set ScrollView's maxHeight dynamically