ConstraintLayout，当约束相关视图消失时，布局视图表现异常 [英] ConstraintLayout, when constraint dependent view is gone, the layout view behave weirdly

问题描述

我正在使用ConstraintLayout，如下所示

I'm using ConstraintLayout where I will show as below

我想隐藏First(使用走了)，我希望它的视图如下所示(ElasticBody会在其中延伸以同时占用原始的First视图空间.

I would like to hide First (using gone), and which the view I expect to be as below (where ElasticBody will stretch over to use up the original First view space as well.

但是，当我实际将First设置为gone时，我的视图显示如下(所有图像均来自Android Studio设计视图).我的Elastic Body也丢失了，高度也怪异地扩展了.

However, when I actual set First to gone, my view turn out to be as below (all image as from Android Studio Design view). My Elastic Body is missing as well, and the height expanded weirdly.

我的布局代码如下

<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:padding="16dp">

    <TextView
        android:id="@+id/txt_first"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#0ff"
        android:text="First"
        android:visibility="gone"
        android:textSize="26sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/txt_body"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/txt_body"
        android:layout_width="0dp"
        android:background="#f0f"
        android:layout_height="wrap_content"
        android:text="Elastic Body"
        android:textSize="26sp"

        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/txt_tail"
        app:layout_constraintStart_toEndOf="@+id/txt_first"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/txt_tail"
        android:background="#ff0"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Tail"
        android:textSize="26sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@+id/txt_body"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

(注意，如果删除gone，将获得第一个图像视图). 为什么会这样呢?当我的First消失时，如何解决?Elastic Body是否可以正确伸展?

(Note, if you remove the gone, you'll get the first image view). Why is this so? How could I fix it where when my First is gone, I could the Elastic Body stretch out correctly?

p/s:我知道如何在LinearLayout和RelativeLayout中进行操作...但是想知道这是否对ConstraintLayout有所限制吗?

p/s: I know how to do it in LinearLayout and RelativeLayout... but wonder if this is a limitation on ConstraintLayout?

推荐答案

尝试关注.

将第一个视图的左侧和顶部约束设置为父".之后:

Set the first view's left and top constraints to "parent". After that:

• 将txt_body文本视图的宽度设置为"0dp"
• 将左约束设置为第一个视图的右侧
• 在尾视图的左侧设置右约束.

因此，每当您将第一个视图的可见性设置为"gone"时，主体视图就会像您想要的那样被拉伸.

So, whenever you set the first view's visibility to "gone", the body view will be stretched like how you want it.

<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:padding="16dp">

    <TextView
        android:id="@+id/txt_first"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#0ff"
        android:text="First"
        android:textSize="26sp"
        android:visibility="gone"
        app:layout_constraintEnd_toStartOf="@+id/txt_body"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent" />

    <TextView
        android:id="@+id/txt_body"
        android:layout_width="0dp"
        android:background="#f0f"
        android:layout_height="wrap_content"
        android:text="Elastic Body"
        android:textSize="26sp"
        app:layout_constraintRight_toLeftOf="@+id/txt_tail"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toRightOf="@+id/txt_first"
        />

    <TextView
        android:id="@+id/txt_tail"
        android:background="#ff0"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Tail"
        android:textSize="26sp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintRight_toRightOf="parent" />

</android.support.constraint.ConstraintLayout>

更新

如果您想使用障碍物，那么也可以做到.

If you want to do using barrier then also you can do it.

<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"
    android:padding="16dp">

    <TextView
        android:id="@+id/txt_first"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#0ff"
        android:text="First"
        android:textSize="26sp"
        android:visibility="gone"
        app:layout_constraintEnd_toStartOf="@+id/barrier"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/txt_body"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:background="#f0f"
        android:text="Elastic Body"
        android:textSize="26sp"
        app:layout_constraintStart_toEndOf="@+id/barrier"
        app:layout_constraintEnd_toStartOf="@+id/txt_tail"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/txt_tail"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#ff0"
        android:text="Tail"
        android:textSize="26sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <androidx.constraintlayout.widget.Barrier
        android:id="@+id/barrier"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:barrierDirection="start"
        app:constraint_referenced_ids="txt_body,txt_first" />

    <androidx.constraintlayout.widget.Barrier
        android:id="@+id/barrier1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:barrierDirection="end"
        app:constraint_referenced_ids="txt_body,txt_tail" />

</androidx.constraintlayout.widget.ConstraintLayout>

这篇关于ConstraintLayout，当约束相关视图消失时，布局视图表现异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！