问图像在约束布局中具有从顶部开始的页边距

EN

<?xml version="1.0" encoding="utf-8"?>
<ScrollView 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.support.constraint.ConstraintLayout
            android:id="@+id/constraintLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
        <!-- have whatever children you want inside -->
        <ImageView
                app:srcCompat="@drawable/main_header"
                android:id="@+id/img_icon"
                android:layout_width="0dp"
                android:layout_height="0dp"
                android:background="#ffccbb"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:layout_constraintWidth_percent="1"
                android:contentDescription="TODO" app:layout_constraintDimensionRatio="1:1"
                app:layout_constraintHorizontal_bias="0.0" app:layout_constraintVertical_bias="0.0"/>
    </android.support.constraint.ConstraintLayout>
</ScrollView>