Cant move a simple button around a constraint layout

Question

I have a constraint layout defined, and inside it a button. The problem is I cant seem to move the button around as it is fixed on the top left of the screen.

Any help?

<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"
android:padding="16dp"
tools:context=".MainActivity">

<Button
    android:id="@+id/button2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Button" />

Answer 1

That helped for me. Android studio -> Build -> Clean Project.

Answer 2

Please use constraints, in design tab, or Text tab, to position the widget, in addition to adding margin. XML code: app:layout_constraintTop_toTopOf="parent" app:layout_constraintLeft_toLeftOf="parent"

You could add margin in Design tab (properties pane on right-top) and then see the added XML in Text tab to view the change in XML.

By default, in Constraint layout, any widget falls to the right-top if it is not constrained.