Android ConstraintLayout 实例化失败

Question

我在使用 ConstraintLayout 时遇到错误。错误看起来像这样，

Failed to instantiate one or more classes

The following classes could not be instantiated -android.support.constraint.ConstraintLayout

我已经安装了 android 的约束布局和约束布局的求解器。

我的应用程序中有此依赖项gradle 文件：build.gradle

dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
    exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:25.3.0'

compile 'com.android.support.constraint:constraint-layout:1.0.2'


//butterknife for view binding
compile 'com.jakewharton:butterknife:8.6.0'
annotationProcessor 'com.jakewharton:butterknife-compiler:8.6.0'
//bottom bar navigation
compile 'com.roughike:bottom-bar:2.3.1'
//fragment managment library
compile 'com.ncapdevi:frag-nav:2.0.1'
//for ripple animation
compile 'com.balysv:material-ripple:1.0.2'
testCompile 'junit:junit:4.12'

我的 XML 布局是这样的 -

<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"
tools:context="com.cr.priyankjain.customrom.MainActivity">

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

    </android.support.constraint.ConstraintLayout>

所以我的问题是如何消除此错误？

Answer 1

刚刚解决了这个 FragNav 依赖库导致所有布局问题的问题，所以我刚刚从 gradle 文件中删除了这一行。

compile 'com.ncapdevi:frag-nav:2.0.1'

Android ConstraintLayout 实例化失败

Android ConstraintLayout failed to instantiated

java

android

android-layout

android-constraintlayout