Resources$NotFoundException

[MummyDing]

I run the project,and it occurs the following exception:

Process: com.example.customview, PID: 25757 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.customview/com.example.customview.MainActivity}: android.content.res.Resources$NotFoundException: Resource ID #0x7f020004

at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2610) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2684) at android.app.ActivityThread.access$800(ActivityThread.java:177) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1542) at android.os.Handler.dispatchMessage(Handler.java:111) at android.os.Looper.loop(Looper.java:194) at android.app.ActivityThread.main(ActivityThread.java:5743) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:988) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:783) Caused by: android.content.res.Resources$NotFoundException: Resource ID #0x7f020004 at android.content.res.Resources.getValue(Resources.java:1484) at android.content.res.Resources.getDrawable(Resources.java:912) at android.content.Context.getDrawable(Context.java:413) at com.android.internal.widget.ToolbarWidgetWrapper.setIcon(ToolbarWidgetWrapper.java:321) at com.android.internal.widget.ActionBarOverlayLayout.setIcon(ActionBarOverlayLayout.java:738) at com.android.internal.policy.impl.PhoneWindow.setDefaultIcon(PhoneWindow.java:1735) at android.app.Activity.initWindowDecorActionBar(Activity.java:2184) at android.app.Activity.setContentView(Activity.java:2219) at com.example.customview.MainActivity.onCreate(MainActivity.java:45) at android.app.Activity.performCreate(Activity.java:6119) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1115) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2557) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2684)  at android.app.ActivityThread.access$800(ActivityThread.java:177)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1542)  at android.os.Handler.dispatchMessage(Handler.java:111)  at android.os.Looper.loop(Looper.java:194)  at android.app.ActivityThread.main(ActivityThread.java:5743)  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:988)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:783)