我的应用程序中有一个按钮,应该在单击时启动另一个活动。我在按钮中添加了一个android:onClick属性,如下所示:
<android.support.v7.widget.AppCompatButton
android:id="@+id/btn_show_toc_id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="false"
android:layout_centerHorizontal="true"
android:text="@string/show_book_content"
android:onClick="showTOC"
/>
showTOC的实现如下:
public void showTOC(View view) {
intent= new Intent(CoverActivity.this,MainActivity.class);
intent.putExtra(EXTRA_MESSAGE,true);
startActivity(intent);
}
这在Nougat(模拟器)和Marshmallow(手机)中运行良好,但每次单击按钮时都会在Jelly Bean(模拟器和手机)上崩溃,并显示错误对话框“不幸[App Name]已停止”。
有趣的是,使用“Button”代替AppCompatButton或使用onClickListener解决了这个问题。有谁知道为什么会这样?
发生错误后,堆栈跟踪(来自Android Monitor的输出):
06-01 11:55:16.352 3480-3480/mypackage.khateratebook E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.IllegalStateException: Could not find a method showTOC(View) in the activity class android.support.v7.widget.TintContextWrapper for onClick handler on view class android.support.v7.widget.AppCompatButton with id 'btn_show_toc_id'
at android.view.View$1.onClick(View.java:3586)
at android.view.View.performClick(View.java:4204)
at android.view.View$PerformClick.run(View.java:17355)
at android.os.Handler.handleCallback(Handler.java:725)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5041)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NoSuchMethodException: showTOC [class android.view.View]
at java.lang.Class.getConstructorOrMethod(Class.java:460)
at java.lang.Class.getMethod(Class.java:915)
at android.view.View$1.onClick(View.java:3579)
at android.view.View.performClick(View.java:4204)
at android.view.View$PerformClick.run(View.java:17355)
at android.os.Handler.handleCallback(Handler.java:725)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5041)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
styles.xml的内容:
<resources>
<!-- Base application theme. -->
<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="BookTheme" parent="Theme.AppCompat.DayNight.NoActionBar">
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
</style>
</resources>
我使用BookTheme风格的唯一地方是我的第三个活动,即以下列方式的activity_main2.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="mypackage.khateratebook.MainActivity2">
<WebView
android:id="@+id/webview_id"
android:layout_width="match_parent"
android:layout_height="495dp"
tools:layout_editor_absoluteX="8dp"
tools:layout_editor_absoluteY="100dp"
android:theme="@style/BookTheme"
android:textDirection="rtl"
/>
</RelativeLayout>