please help me i keep my appliction keep crashing when i open it

Question

E/: Cannot load libgui-plugin D/AndroidRuntime: Shutting down VM E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.ayushjain.myapplication33, PID: 24308 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.ayushjain.myapplication33/com.example.ayushjain.myapplication33.Main2Activity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2911) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2989) at android.app.ActivityThread.-wrap11(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1688) at android.os.Handler.dispatchMessage(Handler.java:106) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6753) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:482) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at com.example.ayushjain.myapplication33.Main2Activity.onCreate(Main2Activity.java:37) at android.app.Activity.performCreate(Activity.java:7041) at android.app.Activity.performCreate(Activity.java:7032) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1231) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2864) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2989)  at android.app.ActivityThread.-wrap11(Unknown Source:0)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1688)  at android.os.Handler.dispatchMessage(Handler.java:106)  at android.os.Looper.loop(Looper.java:164)  at android.app.ActivityThread.main(ActivityThread.java:6753)  at java.lang.reflect.Method.invoke(Native Method)  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:482)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) 

Answer 1

you did not instantiate your button before executing the Button.setOnClickListener so you can solve this way,

Button your_button = (Button) findViewById(R.id. your_button);

then add your click listener like below,

your_button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
//do your stuff
});