我一直试图创建3天的自定义视图。我已经按照每个教程进行了操作，但我不断收到错误＆＃34; ClassNotFoundException＆＃34;。我想制作一个操纵杆，但为了简化这个问题，我试图扩展Button并使用它，我无法成功。
MainActivity.java：
package com.stefan.example;
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.AttributeSet;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
public class CustomButton extends Button
{
public CustomButton(Context context) {
super(context);
}
public CustomButton(Context context, AttributeSet attrs) {
super(context, attrs);
}
public CustomButton(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
acitivity_main.xml：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.stefan.example.MainActivity">
<com.stefan.example.MainActivity.CustomButton
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
它根本不会在编译时抱怨，但是一旦我启动应用程序，它就会崩溃并出现此错误：
10-14 17:31:58.476 15869-15869/com.stefan.example E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.stefan.example, PID: 15869
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.stefan.example/com.stefan.example.MainActivity}: android.view.InflateException: Binary XML file line #12: Error inflating class com.stefan.example.MainActivity.CustomButton
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2306)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2366)
at android.app.ActivityThread.access$800(ActivityThread.java:149)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1284)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5297)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)
Caused by: android.view.InflateException: Binary XML file line #12: Error inflating class com.stefan.example.MainActivity.CustomButton
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:757)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)
at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
at android.view.LayoutInflater.inflate(LayoutInflater.java:365)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
at com.stefan.example.MainActivity.onCreate(MainActivity.java:30)
at android.app.Activity.performCreate(Activity.java:6020)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2259)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2366)
at android.app.ActivityThread.access$800(ActivityThread.java:149)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1284)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5297)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.stefan.example.MainActivity.CustomButton" on path: DexPathList[[zip file "/data/app/com.stefan.example-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
at android.view.LayoutInflater.createView(LayoutInflater.java:571)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:743)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)
at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
at android.view.LayoutInflater.inflate(LayoutInflater.java:365)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
at com.stefan.example.MainActivity.onCreate(MainActivity.java:30)
at android.app.Activity.performCreate(Activity.java:6020)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2259)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2366)
at android.app.ActivityThread.access$800(ActivityThread.java:149)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1284)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5297)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)
Suppressed: java.lang.ClassNotFoundException: Didn't find class "com.stefan.example.MainActivity.CustomButton" on path: DexPathList[[dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-support-annotations-24.1.1_6ce5cf7d8fc68e278012c1fdb63847d6984b1a82-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_9-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_8-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_7-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_6-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_5-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_4-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_3-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_2-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_1-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-slice_0-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-internal_impl-24.1.1_d7334ac7335287759c12e17e515a73749d4ea418-classes.dex", dex file "/data/data/com.stefan.example/files/instant-run/dex/slice-com.android.support-support-vector-drawable-24.1.1_e21575ccf9da39363d36f579d76036b9825e0829-classes.dex
我尝试过更改xml文件：
<Button
class = "com.stefan.example.MainActivity.CustomButton"
android:layout_width="match_parent"
android:layout_height="match_parent" />
它运行，但视图的行为类似于普通按钮，我的类未被使用。
我已经在不同设备上试用了该应用;都给出了同样的例外。
我会忘记一些事吗？我希望我犯了一个简单的错误。 提前谢谢！
答案 0 :(得分：1)
将CustomButton班级移至最高级别，或将其设为static。 LayoutInflater无法实例化您的类，因为它是非静态内部类。