Question

我正在尝试为recyclerview设计自定义字段，但我遇到了有关ConstraintLayout的问题。使用该设计，我将所有设计元素移动到我想要的位置，但是一旦我添加任何类型的约束（使用Infer Contstraints或直接在XML文件中编写，所有元素都移动到完全不同的位置，这绝不是我如何定位它们。这是我的XML代码：

<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:id="@+id/relativeLayout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="@drawable/list_row_selector"
android:padding="8dp"
tools:layout_editor_absoluteY="81dp">

<!-- Thumbnail Image -->
<ImageView
    android:id="@+id/thumbnail"
    android:layout_width="87dp"
    android:layout_height="89dp"
    tools:layout_editor_absoluteX="0dp"
    tools:layout_editor_absoluteY="8dp" />

<!-- Movie Title -->
<TextView
    android:id="@+id/title"
    android:layout_width="216dp"
    android:layout_height="wrap_content"
    android:textSize="@dimen/title"
    android:textStyle="bold"
    tools:layout_editor_absoluteX="90dp"
    tools:layout_editor_absoluteY="8dp" />

<!-- Rating -->
<TextView
    android:id="@+id/rating"
    android:layout_width="72dp"
    android:layout_height="21dp"
    android:textSize="@dimen/rating"
    tools:layout_editor_absoluteX="90dp"
    tools:layout_editor_absoluteY="85dp" />

<!-- Genre -->
<TextView
    android:id="@+id/genre"
    android:layout_width="334dp"
    android:layout_height="28dp"
    android:textColor="@color/genre"
    android:textSize="@dimen/genre"
    tools:layout_editor_absoluteX="0dp"
    tools:layout_editor_absoluteY="114dp" />

<!-- Release Year -->
<TextView
    android:id="@+id/releaseYear"
    android:layout_width="129dp"
    android:layout_height="21dp"
    android:textColor="@color/year"
    android:textSize="@dimen/year"
    tools:layout_editor_absoluteX="172dp"
    tools:layout_editor_absoluteY="85dp" />

<ImageView
    android:id="@+id/btnBookOption"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:focusable="false"
    android:src="@drawable/book_add_touch"
    android:textColor="@color/white"
    tools:ignore="RtlHardcoded"
    tools:layout_editor_absoluteX="304dp"
    tools:layout_editor_absoluteY="39dp" />

<TextView
    android:id="@+id/author"
    android:layout_width="195dp"
    android:layout_height="38dp"
    tools:layout_editor_absoluteX="90dp"
    tools:layout_editor_absoluteY="39dp" />

</android.support.constraint.ConstraintLayout>

以下是我尝试查看列表的方式：

以下是我添加约束

后的看法

如何添加约束，但是同时使布局看起来像第一张图片？谢谢。

Answer 1

您必须正确创建约束。您可以check the documentation了解更多详情。

请注意，tools带注释的参数仅适用于development preview。运行应用程序时，编译器会删除这些参数。

<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:id="@+id/relativeLayout"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:padding="8dp"
    tools:layout_editor_absoluteY="81dp">

    <!-- Thumbnail Image -->
    <ImageView
        android:id="@+id/thumbnail"
        android:layout_width="87dp"
        android:layout_height="89dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:layout_editor_absoluteX="0dp"
        tools:layout_editor_absoluteY="8dp" />

    <!-- Movie Title -->
    <TextView
        android:id="@+id/title"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="8dp"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@id/thumbnail"
        app:layout_constraintTop_toTopOf="@id/thumbnail"
        tools:layout_editor_absoluteX="90dp"
        tools:layout_editor_absoluteY="8dp" />

    <!-- Rating -->
    <TextView
        android:id="@+id/rating"
        android:layout_width="72dp"
        android:layout_height="21dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintStart_toEndOf="@id/thumbnail"
        app:layout_constraintTop_toBottomOf="@id/author"
        tools:layout_editor_absoluteX="90dp"
        tools:layout_editor_absoluteY="85dp" />

    <!-- Genre -->
    <TextView
        android:id="@+id/genre"
        android:layout_width="334dp"
        android:layout_height="28dp"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        tools:layout_editor_absoluteX="0dp"
        tools:layout_editor_absoluteY="114dp" />

    <!-- Release Year -->
    <TextView
        android:id="@+id/releaseYear"
        android:layout_width="129dp"
        android:layout_height="21dp"
        android:layout_marginStart="8dp"
        app:layout_constraintStart_toEndOf="@id/rating"
        tools:layout_editor_absoluteX="172dp"
        tools:layout_editor_absoluteY="85dp" />

    <ImageView
        android:id="@+id/btnBookOption"
        android:layout_width="24dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:focusable="false"
        app:layout_constraintBottom_toTopOf="@id/releaseYear"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@id/author"
        app:layout_constraintTop_toBottomOf="@id/title"
        tools:ignore="RtlHardcoded"
        tools:layout_editor_absoluteX="304dp"
        tools:layout_editor_absoluteY="39dp" />

    <TextView
        android:id="@+id/author"
        android:layout_width="0dp"
        android:layout_height="38dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="8dp"
        app:layout_constraintEnd_toStartOf="@id/btnBookOption"
        app:layout_constraintStart_toEndOf="@id/thumbnail"
        app:layout_constraintTop_toBottomOf="@id/title"
        tools:layout_editor_absoluteX="90dp"
        tools:layout_editor_absoluteY="39dp" />

<android.support.constraint.ConstraintLayout>

Answer 2

试试这个..

<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:id="@+id/relativeLayout"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="@android:color/white"
    android:padding="8dp"
    tools:layout_editor_absoluteY="81dp">

    <!-- Thumbnail Image -->
    <ImageView
        android:id="@+id/thumbnail"
        android:layout_width="87dp"
        android:layout_height="89dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:background="@tools:sample/backgrounds/scenic" />

    <!-- Movie Title -->
    <TextView
        android:id="@+id/title"
        android:layout_width="216dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:textSize="18sp"
        android:textStyle="bold"
        app:layout_constraintStart_toEndOf="@id/thumbnail"
        tools:text="@tools:sample/first_names" />

    <!-- Rating -->
    <TextView
        android:id="@+id/rating"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:textSize="@dimen/rating"
        app:layout_constraintEnd_toStartOf="@+id/releaseYear"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintHorizontal_chainStyle="spread"
        app:layout_constraintHorizontal_weight="3"
        app:layout_constraintStart_toEndOf="@+id/thumbnail"
        app:layout_constraintTop_toBottomOf="@id/btnBookOption"
        tools:text="@tools:sample/us_zipcodes" />

    <!-- Genre -->
    <TextView
        android:id="@+id/genre"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="20dp"
        android:layout_marginTop="12dp"
        android:textColor="@color/genre"
        android:textSize="@dimen/genre"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/rating"
        tools:text="@tools:sample/cities" />

    <!-- Release Year -->
    <TextView
        android:id="@+id/releaseYear"
        android:layout_width="129dp"
        android:layout_height="21dp"
        android:textColor="@color/year"
        android:textSize="@dimen/year"
        app:layout_constraintEnd_toStartOf="@id/btnBookOption"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintHorizontal_weight="5"
        app:layout_constraintStart_toEndOf="@+id/rating"
        app:layout_constraintTop_toBottomOf="@id/btnBookOption"
        tools:text="@tools:sample/date/ddmmyy" />

    <TextView
        android:id="@+id/author"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        app:layout_constraintTop_toTopOf="@id/btnBookOption"
        app:layout_constraintBottom_toBottomOf="@id/btnBookOption"
        app:layout_constraintEnd_toStartOf="@+id/btnBookOption"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintHorizontal_weight="1"
        app:layout_constraintStart_toEndOf="@+id/thumbnail"
        tools:text="@tools:sample/full_names" />

    <ImageView
        android:id="@+id/btnBookOption"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:focusable="false"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/author"
        app:layout_constraintTop_toBottomOf="@id/title"
        tools:ignore="RtlHardcoded"
        tools:src="@android:drawable/alert_dark_frame" />


</android.support.constraint.ConstraintLayout>

ConstraintLayout，添加约束会移动我的所有元素

2 个答案: