有什么方法可以在距离约束布局处设置障碍或在没有约束的一侧向视图添加边距？

Question

要在约束布局中为一组视图设置背景，想法是创建一个视图项并将其约束到极端视图的边界。 但是如果一个组仅依赖于右侧约束，则无法在左侧添加边距，因此可能设置背景的视图组没有左侧填充，

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <data>
        <import type="android.view.View"/>
        <variable
            name="audio"
            type="example.model.observables.AttachmentObservableModel"/>
    </data>

    <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="10dp"
        android:background="@drawable/selector_chat_row"
        >

        <include
            android:id="@+id/message_preview_layout"
            layout="@layout/reply_preview_layout"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:minWidth="160dp"
            android:layout_marginLeft="10dp"
            app:layout_constraintRight_toLeftOf="@+id/guideline"

            app:layout_constraintTop_toTopOf="parent" />

        <android.support.constraint.Barrier
            android:id="@+id/left_barrier"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            app:barrierDirection="left"
            app:constraint_referenced_ids="play_pause,message_preview_layout" />

        <View
            android:id="@+id/view"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="@drawable/chat_me_background"
            app:layout_constraintBottom_toBottomOf="@+id/play_pause"
            app:layout_constraintLeft_toLeftOf="@+id/left_barrier"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <ImageButton
            android:id="@+id/play_pause"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dp"
            android:layout_marginTop="10dp"
            android:layout_marginRight="10dp"
            android:layout_marginBottom="10dp"
            android:background="@null"
            android:enabled="@{!(audio.filePath == null || audio.filePath.isEmpty())}"
            android:onClick="@{() -> audio.playing? audio.onPausePressed(): audio.onPlayPressed()}"
            android:paddingLeft="10dp"
            android:paddingBottom="10dp"
            android:src="@{audio.playing? @drawable/ic_pause_circle_filled: @drawable/ic_play_arrow}"
            app:layout_constraintRight_toLeftOf="@+id/seekbar"
            app:layout_constraintTop_toBottomOf="@+id/message_preview_layout" />

        <android.support.v7.widget.AppCompatSeekBar
            android:id="@+id/seekbar"
            android:layout_width="170dp"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:enabled="@{!(audio.filePath == null || audio.filePath.isEmpty() || !audio.playing)}"
            android:max="@{audio.max}"
            android:onProgressChanged="@{audio::onProgressChanged}"
            android:paddingStart="10dp"
            android:paddingRight="10dp"
            android:paddingBottom="10dp"
            android:progress="@{audio.progress}"
            android:progressTint="@color/selected"
            android:secondaryProgressTint="@color/colorAccent"
            android:thumbTint="@color/colorWhite"
            app:layout_constraintBottom_toBottomOf="@+id/play_pause"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="@+id/play_pause" />

        <ProgressBar

            android:id="@+id/progress"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:indeterminateTint="@color/color_offline"
            android:visibility="@{(audio.filePath == null ||audio.filePath.isEmpty())? View.VISIBLE:View.GONE}"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintLeft_toLeftOf="@+id/play_pause"
            app:layout_constraintRight_toRightOf="@+id/seekbar"
            app:layout_constraintTop_toTopOf="parent"
            style="?android:attr/progressBarStyleSmall"/>

        <android.support.constraint.Guideline
            android:id="@+id/guideline"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            app:layout_constraintGuide_end="15dp"
            />

    </android.support.constraint.ConstraintLayout>
</layout>

这里我想在左侧添加一些填充，其中“视图”是所有视图的背景，但顶部约束布局具有不同的背景。 目前它看起来像这样

Answer 1

找到了解决办法。

在屏障左侧添加一个空视图，宽度为所需的填充。

<View
            android:id="@+id/left_view"
            android:layout_width="15dp"
            android:layout_height="1dp"
            app:layout_constraintRight_toLeftOf="@+id/left_barrier"/>

现在将背景视图的左侧设置为该视图的左侧。 即改变

<View
            android:id="@+id/view"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="@drawable/chat_me_background"
            app:layout_constraintBottom_toBottomOf="@+id/play_pause"
            app:layout_constraintLeft_toLeftOf="@+id/left_barrier"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

到

<View
            android:id="@+id/view"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="@drawable/chat_me_background"
            app:layout_constraintBottom_toBottomOf="@+id/play_pause"
            app:layout_constraintLeft_toLeftOf="@+id/left_view"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

Answer 2

只需添加barrierMargin:

 <androidx.constraintlayout.widget.Barrier
    app:barrierMargin="3dp"
    android:id="@+id/barrier"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    app:barrierDirection="end"
    app:constraint_referenced_ids="textView4,textView3,textView2"
    tools:layout_editor_absoluteX="167dp"
    tools:layout_editor_absoluteY="44dp" />