android 虚拟设备中的布局与布局预览和真实设备中的布局不同

android layout in virtual device is not the same as in layout preview and real device

环境:
Android Studio 3.4.1
activity_main.xml代码

<?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"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/editText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="16dp"
        android:ems="10"
        android:hint="@string/edit_message"
        android:inputType="textPersonName"
        app:layout_constraintEnd_toStartOf="@+id/button"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginEnd="16dp"
        android:layout_marginRight="16dp"
        android:onClick="sendMessage"
        android:text="@string/button_send"
        app:layout_constraintBaseline_toBaselineOf="@+id/editText"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/editText" />
</androidx.constraintlayout.widget.ConstraintLayout>

在android工作室布局设计选项卡中,显示如下。

my real phone device profile :
resolution: 1440x720 px
screen size: 5.45 inch
android version: 8.1.0

在真机上正常显示

While in android studio virtual device EditText's hint message is not completely displayed.
virtual device profile:
resoluton: 480x800
density: hdpi
API: 26
Target:Android 8.0(Google APIs)
Size: 4.0 inch

您可以尝试使用 LinearLayout 而不是 ConstraintLayout。它将轻松解决您的问题。

代码

 <LinearLayout
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:orientation="horizontal">


<EditText
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="0.75"
    android:hint="Enter a message"/>


<Button
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="0.25"
    android:text="Button"/>