我完全照著老師的代碼敲的 ，可是就是點(diǎn)擊沒有反應(yīng)，就好像start方法沒用一樣

public class MainActivity extends AppCompatActivity {
? ?private wuziqi_panel wuziqiPanel;

? ?@Override
? ?protected void onCreate(Bundle savedInstanceState) {
? ? ? ?super.onCreate(savedInstanceState);
? ? ? ?setContentView(R.layout.activity_main);

? ? ? ?wuziqiPanel = (wuziqi_panel) findViewById(R.id.wuziqi);

? ? ? ?Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
? ? ? ?setSupportActionBar(toolbar);

? ? ? ?FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
? ? ? ?fab.setOnClickListener(new View.OnClickListener() {
? ? ? ? ? ?@Override
? ? ? ? ? ?public void onClick(View view) {
? ? ? ? ? ? ? ?Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
? ? ? ? ? ? ? ? ? ? ? ?.setAction("Action", null).show();
? ? ? ? ? ?}
? ? ? ?});
? ?}

? ?@Override
? ?public boolean onCreateOptionsMenu(Menu menu) {
? ? ? ?// Inflate the menu; this adds items to the action bar if it is present.
? ? ? ?getMenuInflater().inflate(R.menu.menu_main, menu);
? ? ? ?return true;
? ?}

? ?@Override
? ?public boolean onOptionsItemSelected(MenuItem item) {
? ? ? ?// Handle action bar item clicks here. The action bar will
? ? ? ?// automatically handle clicks on the Home/Up button, so long
? ? ? ?// as you specify a parent activity in AndroidManifest.xml.
? ? ? ?int id = item.getItemId();

? ? ? ?//noinspection SimplifiableIfStatement
? ? ? ?if (id == R.id.action_settings) {
? ? ? ? ? ?wuziqiPanel.start();
? ? ? ? ? ?return true;
? ? ? ?}

? ? ? ?return super.onOptionsItemSelected(item);
? ?}

public void start(){
? ?mWhiteArray.clear();
? ?mBlackArray.clear();
? ?mIsGameOver = false;
? ?misWhiteWinner = false;
? ?invalidate();
}