Initialize the app

public class MainActivity extends AppCompatActivity {

    private final String TAG = "MainActivity";
    static final int DEVICE_ADMIN_ADD_RESULT_ENABLE = 1;

    private Button mToggleAdminBtn;
    private ComponentName mDeviceAdmin;
    private DevicePolicyManager mDPM;
    private Utils mUtils;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        //...called when the activity is starting. This is where most initialization should go.
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TextView LogView = (TextView) findViewById(R.id.logview_id);
        LogView.setMovementMethod(new ScrollingMovementMethod());
        mToggleAdminBtn = (Button) findViewById(R.id.ToggleAdminbtn);
        Button ActivateLicenseBtn = (Button) findViewById(R.id.ActivateLicencebtn);
        Button ShowEnabledAppsBtn = (Button) findViewById(R.id.ShowEnabledAppsbtn);
        Button ShowDisabledAppsBtn = (Button) findViewById(R.id.ShowDisabledAppsbtn);
        Button EnableAllDisabledAppsBtn = (Button) findViewById(R.id.EnableAllDisabledAppsbtn);
        Button EnableGivenAppBtn = (Button) findViewById(R.id.EnableGivenAppbtn);
        Button DisableGivenAppBtn = (Button) findViewById(R.id.DisableGivenAppbtn);

        mDeviceAdmin = new ComponentName(MainActivity.this, SampleAdminReceiver.class);
        mDPM = (DevicePolicyManager) getSystemService(Context.DEVICE_POLICY_SERVICE);
        mUtils = new Utils(LogView, TAG);

        // Check if device supports Knox SDK
        mUtils.checkApiLevel(24, this);

        mToggleAdminBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {toggleAdmin();
            }
        });
        ActivateLicenseBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                activateLicense();
            }
        });
        ShowEnabledAppsBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                showAppState(true);
            }
        });
        ShowDisabledAppsBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                showAppState(false);
            }
        });
        EnableAllDisabledAppsBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) { enableAllDisabledApps();
            }
        });
        EnableGivenAppBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) { promptUserForPackageName(true);
            }
        });
        DisableGivenAppBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) { promptUserForPackageName(false);
            }
        });
    }

    //the logic for onClickListener functions are done here

}