How to set a view's height match parent in ConstraintLayout?

问题

I am creating a layout.I want to set my custom toolbar(Which is another layout) to the top of layout and the FrameLayout just below the toolbar. But the FrameLayout should get rest of the layout's height(match_parent).How to achieve this using constraint layout ?

Thank you in advance.

回答1:

Use 0dp that is match_contraint in ConstraintLayout.

Like android:layout_height="0dp"

回答2:

Solution: I'm assuming that you have your toolbar as another xml file, something like this:

toolbar.xml

<android.support.v7.widget.Toolbar
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:minHeight="60dp"
    android:background="?attr/colorPrimary"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

then using ConstraintLayout use it with FrameLayout 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"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <include
        android:id="@+id/toolbar"
        layout="@layout/toolbar"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <FrameLayout
        android:id="@+id/container"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/toolbar" />

</android.support.constraint.ConstraintLayout>

Hope this helps. Please comment if you have any issues with it.

回答3:

Note, that unlike other viewgroups in android, constraintlayout should have circular dependencies between the child views. Herewith, you should use 0dp instead of 'match_parent' width and constraints for each side of the child view.

<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">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="0dp"
        android:layout_height="?attr/actionBarSize"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"/>

    <FrameLayout
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/toolbar"/>

</android.support.constraint.ConstraintLayout>

回答4:

give the toolbar an id , and in your frame layout set the width and height to 0dp add the constraints like in this code..

<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context=".Main2Activity">

    <Toolbar
        android:id="@+id/toolbar"
        app:layout_constraintTop_toTopOf="parent"
        android:background="#ab1010"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

    </Toolbar>

    <FrameLayout
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintTop_toBottomOf="@id/toolbar"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        android:background="#f1f1df"
        >

    </FrameLayout>


</android.support.constraint.ConstraintLayout>

来源：https://stackoverflow.com/questions/53299024/how-to-set-a-views-height-match-parent-in-constraintlayout