My Application Crashes On Startup

My app crashes on startup without showing any error. I can't find why. I tried many solutions, but in vain here is MainActivity.java package com.example.android.mycourses; import

Solution 1:

Try cleaning your build: (Settings -> Applications -> MyApp -> Memory -> Clear data) has been known to fix class loader problems.

Otherwise there might be a problem in your xml layouts.

Solution 2:

These need to be in the adapter, not the Activity if you want the app to run

courseTV = (TextView) findViewById(R.id.messageTextView);

checkbox = ( CheckBox ) findViewById( R.id.checkbox );
checkbox.setOnCheckedChangeListener

Neither of those views are inside activity_main