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Android

David Kotecki
David Kotecki
162 Points
Posted by David Kotecki
David Kotecki
162 Points

I need help with android studio error I get when trying to run my app

I tried running my app and get this error I am building this app for my senior project and could use help 09-18 15:46:12.936 26761-26761/mteck.skylinehighschooleventsapp E/AndroidRuntime: FATAL EXCEPTION: main Process: mteck.skylinehighschooleventsapp, PID: 26761 java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at mteck.skylinehighschooleventsapp.MainActivity.onNavigationItemSelected(MainActivity.java:112) at android.support.design.widget.NavigationView$1.onMenuItemSelected(NavigationView.java:153) at android.support.v7.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:810) at android.support.v7.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:152) at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:957) at android.support.design.internal.NavigationMenuPresenter$1.onClick(NavigationMenuPresenter.java:328) at android.view.View.performClick(View.java:5697) at android.view.View$PerformClick.run(View.java:22526) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:158) at android.app.ActivityThread.main(ActivityThread.java:7224) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) 09-18 15:46:14.746 26761-26761/mteck.skylinehighschooleventsapp I/Process: Sending signal. PID: 26761 SIG: 9

1 Answer

Alvin Abia
PLUS
Alvin Abia
Courses Plus Student 23,034 Points
Alvin Abia
Alvin Abia
Courses Plus Student 23,034 Points

You are trying to set an on click listener on a button reference that is null. Make sure that you set the button reference's value, 

// Put this in your activity's onCreate method.
mButton = findViewById(R.id.whateverYourButtonIdIs);

// or if you're using ButterKnife, put this when you declare your member variable.
BindView(R.id.whateverYourButtonIdIs) Button mButton;