class 내에서 layout background 수정
setContentView(R.layout.main); // Now get a handle to any View contained // within the main layout you are using View someView = findViewById(R.id.randomViewInMainLayout); // Find the root view View root = someView.getRootView() // Set the color root.setBackgroundColor(android.R.color.red); 출처 ; http://stackoverflow.com/questions/4761686/how-to-set-background-color-of-activity-to-white-programma..