膨胀Android中的浮动操作按钮时出错

Question

I get this error in my XML file :

java.lang.NoSuchMethodError: android.support.v7.widget.AppCompatImageHelper.<init>(Landroid/widget/ImageView;Landroid/support/v7/widget/AppCompatDrawableManager;)V
at android.support.design.widget.FloatingActionButton.<init>(FloatingActionButton.java:133)
at android.support.design.widget.FloatingActionButton.<init>(FloatingActionButton.java:110)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:465)
at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:172)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:105)
at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:186)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:334)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:345)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:245)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:727)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:858)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:70)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:834)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:518)
at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:324)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:429)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:389)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:548)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:533)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:966)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:533)
at com.android.tools.idea.rendering.RenderTask.lambda$inflate$70(RenderTask.java:659)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)

My XML File is :

<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_input_add"
     />

Gradle File :

compile 'com.android.support:appcompat-v7:23.4.0'
compile 'com.android.support:design:23.4.0'

Styles :

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <!-- Customize your theme here. -->
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>

<style name="AppTheme.NoActionBar">
    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>
</style>

MANIFEST declaration :

<activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:theme="@style/AppTheme.NoActionBar" />

Please help for the above error. The error posted above is while rendering the preview of the xml file. When I run the application the application Stops and it gives an error as Error inflating class android.support.design.widget.FloatingActionButton

Answer 1

com.android.support:appcompat-v7:21+ added support for tinting widgets on devices running pre android 5.1 (API Level 21). To make use of it make sure you extend or set the AppCompat Theme and use app:backgroundTint instead of android:backgroundTint.

<android.support.design.widget.FloatingActionButton 
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="16dp"
android:src="@drawable/icon"
app:backgroundTint="@color/accent"
app:borderWidth="0dp" />

Please change it into AppCompatActivity if you use Activity. Probably it becomes the error when it is Activity.