error inflating class错误

09-11 18:44:20.701: E/AndroidRuntime(401): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.testandroid/com.example.testandroid.draw.CustomView}: android.view.InflateException: Binary XML file line #10:
Error inflating class com.example.testandroid.draw.DrawView

09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.os.Handler.dispatchMessage(Handler.java:99)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.os.Looper.loop(Looper.java:123)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.ActivityThread.main(ActivityThread.java:3683)
09-11 18:44:20.701: E/AndroidRuntime(401): at java.lang.reflect.Method.invokeNative(Native Method)
09-11 18:44:20.701: E/AndroidRuntime(401): at java.lang.reflect.Method.invoke(Method.java:507)
09-11 18:44:20.701: E/AndroidRuntime(401): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
09-11 18:44:20.701: E/AndroidRuntime(401): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
09-11 18:44:20.701: E/AndroidRuntime(401): at dalvik.system.NativeStart.main(Native Method)
09-11 18:44:20.701: E/AndroidRuntime(401): Caused by: android.view.InflateException: Binary XML file line #10: Error inflating class com.example.testandroid.draw.DrawView
09-11 18:44:20.701: E/AndroidRuntime(401): at android.view.LayoutInflater.createView(LayoutInflater.java:508)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:570)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.view.LayoutInflater.rInflate(LayoutInflater.java:623)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
09-11 18:44:20.701: E/AndroidRuntime(401): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:207)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.Activity.setContentView(Activity.java:1657)
09-11 18:44:20.701: E/AndroidRuntime(401): at com.example.testandroid.draw.CustomView.onCreate(CustomView.java:18)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-11 18:44:20.701: E/AndroidRuntime(401): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
09-11 18:44:20.701: E/AndroidRuntime(401): … 11 more

09-11 18:44:20.701: E/AndroidRuntime(401): Caused by: java.lang.NoSuchMethodException: DrawView(Context,AttributeSet)

重点在于最后一句话

 java.lang.NoSuchMethodException: DrawView(Context,AttributeSet)

原因是没有对应的方法，就是没有定义inflate需要的默认构造方法，下面我们就实现它

这样就OK了