18、 Caused by: java.lang.NoSuchMethodException: [class android.content.Context..AttributeSet

錯誤日誌:

Caused by: android.view.InflateException: Binary XML file line #20: Error inflating class sourceforge.titlelan.VisualizerView
            at android.view.LayoutInflater.createView(LayoutInflater.java:606)
            at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:699)
            at android.view.LayoutInflater.rInflate(LayoutInflater.java:758)
            at android.view.LayoutInflater.inflate(LayoutInflater.java:495)
            at android.view.LayoutInflater.inflate(LayoutInflater.java:400)
            at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
            at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:290)
            at android.app.Activity.setContentView(Activity.java:1943)
            at sourceforge.titlelan.MainActivity.onCreate(MainActivity.java:31)
            at android.app.Activity.performCreate(Activity.java:5245)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2164)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2249)
            at android.app.ActivityThread.access$800(ActivityThread.java:141)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1212)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5052)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.NoSuchMethodException: <init> [class android.content.Context, interface android.util.AttributeSet]
            at java.lang.Class.getConstructorOrMethod(Class.java:472)
            at java.lang.Class.getConstructor(Class.java:446)
            at android.view.LayoutInflater.createView(LayoutInflater.java:571)
            at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:699)
            at android.view.LayoutInflater.rInflate(LayoutInflater.java:758)
            at android.view.LayoutInflater.inflate(LayoutInflater.java:495)
            at android.view.LayoutInflater.inflate(LayoutInflater.java:400)
            at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
            at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:290)
            at android.app.Activity.setContentView(Activity.java:1943)
            at sourceforge.titlelan.MainActivity.onCreate(MainActivity.java:31)
            at android.app.Activity.performCreate(Activity.java:5245)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2164)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2249)
            at android.app.ActivityThread.access$800(ActivityThread.java:141)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1212)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5052)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
            at dalvik.system.NativeStart.main(Native Method)

1、上面的VisualizerView是我自定義的控制元件,而控制元件只有下面一個構造方法而已

 

public VisualizerView(Context context) {
     super(context);
     init();
}

2、分析：

<init> [class android.content.Context, interface android.util.AttributeSet]

這裡明確說明在定義view時，沒有重寫含有(Context context,AttributeSet attrs)的構造器

3、解決方案:

在自定義View時，必須要重寫(Context context,AttributeSet attrs)構造方法

public VisualizerView(Context context, AttributeSet attrs) {
    super(context, attrs);
    init();
}