约束布局中的可滚动文本视图

Question

我正在处理约束布局，我有三个视图。第一个在顶部，第二个与视图1相对位置，最后一个在视图2下方。现在，在第二个视图中，我有一个应该是可滚动的文本视图。问题是ScrollView的高度覆盖了整个屏幕，但我希望它具有固定的高度，并且不会将视图3移出屏幕。我不想硬编码ScrollView的高度，所以不知道应该采用什么方式来解决。简而言之，第二个视图应该保持在视图1和视图3之间，无论文本长度如何。

<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:layout_margin="20dp">


    <ImageView
        android:id="@+id/imageView"
        android:layout_width="48dp"
        android:layout_height="48dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/aandn_icon" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="16dp"
        android:layout_marginStart="16dp"
        android:minHeight="48dp"
        android:text="Lorem ipsum"
        app:layout_constraintLeft_toRightOf="@+id/imageView"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="@+id/imageView" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="48dp"
        android:layout_height="48dp"
        android:layout_marginTop="16dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView"
        app:srcCompat="@drawable/aandn_icon" />


    <ScrollView
        android:id="@+id/scrolltext"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        app:layout_constraintLeft_toRightOf="@+id/imageView2"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="@+id/imageView2">

        <android.support.constraint.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">


            <TextView
                android:id="@+id/start_tv4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignBaseline="@+id/sound"
                android:layout_gravity="top|left"
                android:layout_toLeftOf="@+id/sound"
                android:text="Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
Definition: A happening or sudden event that is not wanted or expected.Example: The cars collided unexpectedly on the road causing an accident.||
"
                android:textColor="#000000"
                android:textSize="20sp" />


        </android.support.constraint.ConstraintLayout>

    </ScrollView>

    <ImageView
        android:id="@+id/imageView4"
        android:layout_width="48dp"
        android:layout_height="48dp"
        android:layout_marginTop="16dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/scrolltext"
        app:srcCompat="@drawable/aandn_icon" />

    <TextView
        android:id="@+id/textView4"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="16dp"
        android:layout_marginStart="16dp"
        android:minHeight="48dp"
        android:text="Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. "
        app:layout_constraintLeft_toRightOf="@+id/imageView4"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="@+id/imageView4" />

</android.support.constraint.ConstraintLayout>

这是输出结果

- User42590

---

在第二个TextView中尝试使用android:lines="5"，当超过5行时它将会滚动。 - Vidhi Dave

Answer 1

您想将textView4固定在屏幕底部，并让ScrollView填充在其上方，但在顶部TextView下方。如果我理解正确，这是一种方法：

要将textView4固定在屏幕底部：

<ImageView
    android:id="@+id/imageView4"
    ...
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent" />

这是图片视图，但文本视图与其相关联。

要使用ScrollView填充中心部分：

<ScrollView
    android:id="@+id/scrolltext"
    android:layout_width="0dp"
    android:layout_height="0dp"
    app:layout_constraintBottom_toTopOf="@id/imageView4"
    app:layout_constraintLeft_toRightOf="@+id/imageView2"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="@+id/imageView2"
    app:layout_constraintVertical_bias="0.0">

滚动视图的高度设置为MATCH_CONSTRAINTS（0dp），并且顶部和底部都受到滚动视图相关联的图像视图和底部图像视图的限制。这将使滚动视图在这两个限制之间居中，因此需要垂直偏差来将滚动视图移动到范围的顶部。

- Cheticamp

Answer 2

ConstraintLayout允许您创建具有平面视图层次结构（无嵌套视图组）的大型和复杂布局。 @

<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:layout_margin="20dp">

<ImageView
 android:id="@+id/imageView"
 android:layout_width="48dp"
 android:layout_height="48dp"
 app:layout_constraintLeft_toLeftOf="parent"
 app:layout_constraintTop_toTopOf="parent"
 app:srcCompat="@drawable/ic_launcher"/>

<TextView
 android:id="@+id/textView"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:layout_marginLeft="16dp"
 android:layout_marginStart="16dp"
 android:minHeight="48dp"
 android:text="Lorem ipsum"
 app:layout_constraintLeft_toRightOf="@+id/imageView"
 app:layout_constraintRight_toRightOf="parent"
 app:layout_constraintTop_toTopOf="@+id/imageView"/>

<ImageView
 android:id="@+id/imageView2"
 android:layout_width="48dp"
 android:layout_height="48dp"
 android:layout_marginTop="16dp"
 app:layout_constraintLeft_toLeftOf="parent"
 app:layout_constraintTop_toBottomOf="@+id/textView"
 app:srcCompat="@drawable/ic_launcher"/>


<ScrollView
 android:id="@+id/scrolltext"
 android:layout_width="0dp"
 android:layout_height="0dp"
 app:layout_constraintBottom_toTopOf="@+id/textView4"
 app:layout_constraintHeight_default="wrap"
 app:layout_constraintLeft_toRightOf="@+id/imageView2"
 app:layout_constraintRight_toRightOf="parent"
 app:layout_constraintTop_toTopOf="@+id/imageView2"
 app:layout_constraintVertical_bias="0.0">
    <TextView
     android:id="@+id/start_tv4"
     android:layout_width="wrap_content"
     android:layout_height="0dp"
     android:layout_gravity="top|start"
     android:text="@string/huge_text"
     android:textColor="#000000"
     android:textSize="20sp"
     app:layout_constraintBottom_toTopOf="@+id/textView4"
     app:layout_constraintHeight_default="wrap"/>

</ScrollView>

<ImageView
 android:id="@+id/imageView4"
 android:layout_width="48dp"
 android:layout_height="48dp"
 android:layout_marginTop="16dp"
 app:layout_constraintBottom_toBottomOf="parent"
 app:layout_constraintLeft_toLeftOf="parent"
 app:layout_constraintTop_toBottomOf="@+id/scrolltext"
 app:srcCompat="@drawable/ic_launcher"/>

<TextView
 android:id="@+id/textView4"
 android:layout_width="0dp"
 android:layout_height="0dp"
 android:layout_marginLeft="16dp"
 android:layout_marginStart="16dp"
 android:minHeight="48dp"
 android:text="@string/lorem"
 app:layout_constraintBottom_toBottomOf="parent"
 app:layout_constraintHeight_default="wrap"
 app:layout_constraintLeft_toRightOf="@+id/imageView4"
 app:layout_constraintRight_toRightOf="parent"
 />

其余的可以想出来。

- Johnny