视图被打包在ConstraintLayout中，视图在LinearLayout中用尽屏幕

Question

我正在实现如下所示的注册/登录屏幕

我已经尝试使用ConstraintLayout，如下所示

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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="16dp"
    tools:context=".MainActivity">

    <ImageView
        android:id="@+id/img"
        android:layout_width="250dp"
        android:layout_height="250dp"
        android:layout_marginBottom="72dp"
        android:src="@drawable/ic_launcher_background"
        app:layout_constraintBottom_toTopOf="@+id/btn1"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_chainStyle="packed" />

    <Button
        android:id="@+id/btn1"
        android:layout_width="0dp"
        android:layout_height="56dp"
        android:layout_marginStart="32dp"
        android:layout_marginEnd="32dp"
        android:layout_marginBottom="12dp"
        android:text="Button 1"
        app:layout_constraintBottom_toTopOf="@+id/btn2"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/img" />

    <Button
        android:id="@+id/btn2"
        android:layout_width="0dp"
        android:layout_height="56dp"
        android:layout_marginBottom="48dp"
        android:text="Button 2"
        app:layout_constraintBottom_toTopOf="@+id/txt_already_member"
        app:layout_constraintEnd_toEndOf="@+id/btn1"
        app:layout_constraintStart_toStartOf="@+id/btn1"
        app:layout_constraintTop_toBottomOf="@+id/btn1" />

    <TextView
        android:id="@+id/txt_already_member"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Already Member? Sign In"
        android:textSize="16sp"
        app:layout_constraintBottom_toTopOf="@+id/txt_agreement"
        app:layout_constraintEnd_toEndOf="@+id/btn2"
        app:layout_constraintStart_toStartOf="@+id/btn2"
        app:layout_constraintTop_toBottomOf="@+id/btn2" />

    <TextView
        android:id="@+id/txt_agreement"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="By continuing you agree to our terms and privacy policy"
        android:layout_marginTop="32dp"
        android:textSize="12sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

XML的摘要：

• 垂直链应用于最上面的四个视图
• 垂直链样式设置为压缩
• 最后一个文本视图限制在底部和侧面
• 在视图上设置了页边距以分隔各个项目。

问题是当我在手机上运行此命令时，底部文本视图变得紧凑，如here所示。

接下来我尝试如下所示的LinearLayout

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:gravity="center_horizontal"
    android:layout_margin="16dp"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/img"
        android:layout_width="250dp"
        android:layout_height="250dp"
        android:layout_marginBottom="72dp"
        android:layout_marginTop="72dp"
        android:src="@drawable/ic_launcher_background"/>

    <Button
        android:id="@+id/btn1"
        android:layout_width="match_parent"
        android:layout_height="56dp"
        android:layout_marginStart="32dp"
        android:layout_marginEnd="32dp"
        android:layout_marginBottom="8dp"
        android:text="Button 1" />

    <Button
        android:id="@+id/btn2"
        android:layout_width="match_parent"
        android:layout_marginStart="32dp"
        android:layout_marginEnd="32dp"
        android:layout_height="56dp"
        android:layout_marginBottom="32dp"
        android:text="Button 2" />

    <TextView
        android:id="@+id/txt_already_member"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Already Member? Sign In"
        android:textSize="16sp"
        android:layout_weight="1"/>

    <TextView
        android:id="@+id/txt_agreement"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="By continuing you agree to our terms and privacy policy "
        android:textSize="12sp"/>
</LinearLayout>

在这种情况下，底部文本视图不可见，如here所示。

我的设备分辨率为720 * 1280像素。

我想问题出在硬边距上。无论屏幕高度如何，如何使屏幕看起来像上面的草图一样？使用LinearLayout还是ConstraintLayout？

Answer 1

<?xml version="1.0" encoding="utf-8"?>
<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="match_parent"
android:layout_margin="16dp">

<ImageView
    android:id="@+id/img"
    android:layout_width="@dimen/_200sdp"
    android:layout_height="@dimen/_200sdp"
    android:layout_marginTop="16dp"
    android:src="@drawable/ic_launcher"
    app:layout_constraintBottom_toTopOf="@+id/btn1"
    app:layout_constraintEnd_toStartOf="@+id/right"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="@+id/left"
    app:layout_constraintTop_toTopOf="parent" />

<Button
    android:id="@+id/btn1"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:text="Button 1"
    app:layout_constraintBottom_toTopOf="@+id/btn2"
    app:layout_constraintEnd_toStartOf="@+id/right"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="@+id/left"
    app:layout_constraintTop_toBottomOf="@+id/img" />

<Button
    android:id="@+id/btn2"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:text="Button 2"
    app:layout_constraintBottom_toTopOf="@+id/txt_already_member"
    app:layout_constraintEnd_toStartOf="@+id/right"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="@+id/left"
    app:layout_constraintTop_toBottomOf="@+id/btn1" />

<TextView
    android:id="@+id/txt_already_member"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="20dp"
    android:text="Already Member? Sign In"
    android:textSize="16sp"
    app:layout_constraintBottom_toTopOf="@+id/divider"
    app:layout_constraintEnd_toStartOf="@+id/right"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="@+id/left"
    app:layout_constraintTop_toBottomOf="@+id/btn2" />

<TextView
    android:id="@+id/txt_agreement"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginBottom="24dp"
    android:text="By continuing you agree to our terms and privacy policy"
    android:textSize="12sp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toStartOf="@+id/right"
    app:layout_constraintStart_toStartOf="@+id/left"
    app:layout_constraintTop_toTopOf="@+id/divider"
    app:layout_constraintVertical_bias="1.0" />

<androidx.constraintlayout.widget.Guideline
    android:id="@+id/left"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    app:layout_constraintGuide_begin="@dimen/_16sdp" />

<androidx.constraintlayout.widget.Guideline
    android:id="@+id/right"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    app:layout_constraintGuide_end="@dimen/_16sdp" />

<androidx.constraintlayout.widget.Guideline
    android:id="@+id/divider"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintGuide_percent="0.7"
    app:layout_constraintTop_toBottomOf="@+id/txt_already_member" />

Answer 2

由于app:layout_constraintGuide_percent的值是

percentage