Android Studio 2.2 Preview 3 Layout Error

问题

I just updated my android studio to the 2.2 Preview 3 and on trying the new constraint layout i placed a edittext into the layout and ran the app on my phone but this is what i got

i then tried converting the constraint layout back to how the code was before constraint layout, the results were the same.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    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:fitsSystemWindows="true"
    tools:context="com.ellohinc.constrainttest.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_height="wrap_content"
        android:layout_width="match_parent"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>

    <include layout="@layout/content_main"/>

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="@dimen/fab_margin"
        android:src="@android:drawable/ic_dialog_email" />

content_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/content_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:showIn="@layout/activity_main"
    tools:context="com.ellohinc.constrainttest.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="@+id/content_main"
        app:layout_constraintLeft_toLeftOf="@+id/content_main"
        app:layout_constraintRight_toRightOf="@+id/content_main"
        app:layout_constraintTop_toTopOf="@+id/content_main" />

    </android.support.constraint.ConstraintLayout>

Please any help would be much appreciated.

回答1:

I had the same issue. I resolved it by Downgrading the gradle version. It will stop instant run though.

回答2:

In your gradle file change gradle version under your dependency to lower version like this com.android.tools.build:gradle:2.0.0. It works for me.

来源：https://stackoverflow.com/questions/37908232/android-studio-2-2-preview-3-layout-error