android studioUI控件位置

android studioUI控件位置全在左上角，该怎么解决

<?xml version="1.0" encoding="utf-8"?>
<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"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context=".MainActivity"
    tools:layout_editor_absoluteY="56dp"
    tools:showIn="@layout/activity_main">


    <TextView
        android:id="@+id/textView"
        android:layout_width="0dp"
        android:layout_height="35dp"
        android:layout_marginStart="78dp"
        android:layout_marginLeft="78dp"
        android:layout_marginEnd="20dp"
        android:layout_marginRight="20dp"
        android:gravity="center"
        android:text="用户名"
        android:textSize="20dp"
        app:layout_constraintBaseline_toBaselineOf="@+id/editText"
        app:layout_constraintEnd_toStartOf="@+id/editText"
        app:layout_constraintStart_toStartOf="parent" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="0dp"
        android:layout_height="35dp"
        android:layout_marginStart="78dp"
        android:layout_marginLeft="78dp"
        android:layout_marginEnd="20dp"
        android:layout_marginRight="20dp"
        android:gravity="center"
        android:text="密码"
        android:textSize="20dp"
        app:layout_constraintBaseline_toBaselineOf="@+id/editText2"
        app:layout_constraintEnd_toStartOf="@+id/editText2"
        app:layout_constraintStart_toStartOf="parent" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="登录"
        app:layout_constraintBaseline_toBaselineOf="@+id/button2"
        app:layout_constraintEnd_toEndOf="@+id/textView2" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="46dp"
        android:layout_marginEnd="21dp"
        android:layout_marginRight="21dp"
        android:text="注册"
        app:layout_constraintEnd_toEndOf="@+id/editText2"
        app:layout_constraintTop_toBottomOf="@+id/editText2" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="0dp"
        android:layout_height="35dp"
        android:layout_marginTop="144dp"
        android:layout_marginEnd="67dp"
        android:layout_marginRight="67dp"
        android:ems="10"
        android:inputType="textPersonName"
        android:text=""
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@+id/textView"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="0dp"
        android:layout_height="35dp"
        android:layout_marginTop="70dp"
        android:layout_marginEnd="67dp"
        android:layout_marginRight="67dp"
        android:ems="10"
        android:inputType="numberPassword"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@+id/textView2"
        app:layout_constraintTop_toBottomOf="@+id/editText" />

</android.support.constraint.ConstraintLayout>

https://blog.csdn.net/qq_34489091/article/details/84028063

android.support.constraint.ConstraintLayout改为线性布局Linearlayout