SetOnClickListener按钮不工作Android Studio

Question

我是新来的Java，我试图在Android Studio制作食品应用程序。我在应用中有一个酒吧，当我单击购物车时，我的应用程序正在崩溃。

这是我的主动脉

public class MainActivity extends AppCompatActivity {
private RecyclerView.Adapter adapter, adapter2;
private RecyclerView recyclerViewCategotyList, recyclerViewPopularList;

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

    recyclerViewCategoty();
    recyclerViewPopular();
    bottomNavigation();
}

private void bottomNavigation() {
    LinearLayout homeBtn=findViewById(R.id.homeBtn);
    LinearLayout cartBtn=findViewById(R.id.cartBtn);

    homeBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            startActivity(new Intent(MainActivity.this,MainActivity.class));
        }
    });

    cartBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
           startActivity(new Intent(MainActivity.this,CartActivity.class));
        }
    });
} 

，我有一个错误：在com.example.food.activity.Activity.MainActivity $ 2.Onclick（MainActivity.java:48）

这是一次性的，

public class CartActivity extends AppCompatActivity {
private RecyclerView.Adapter adapter;
private RecyclerView recyclerViewList;
private ManagementCart managementCart;
private TextView totalFeeTxt, taxTxt, deliveryTxt, totalTxt, emptyTxt;
private double tax;
private ScrollView scrollView;

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

    managementCart = new ManagementCart(this);

    initView();
    initList();
    bottomNavigation();
    calculateCard();
}

private void bottomNavigation() {
    LinearLayout homeBtn = findViewById(R.id.homeBtn);
    LinearLayout cartBtn = findViewById(R.id.cartBtn);

    homeBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            startActivity(new Intent(CartActivity.this, MainActivity.class));
        }
    });

    cartBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            startActivity(new Intent(CartActivity.this, MainActivity.class));
        }
    });
} 

我不知道有什么问题，以及为什么我的SetOnClicklistener不起作用。

谢谢。

Answer 1

我认为您的按钮r.id.homebtn不是线性的，您可以显示XML文件吗？

如果您的按钮是按钮类，请尝试

private void bottomNavigation() {
    Button homeBtn = findViewById(R.id.homeBtn);
    Button cartBtn = findViewById(R.id.cartBtn);

    homeBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            startActivity(new Intent(CartActivity.this, MainActivity.class));
        }
    });

    cartBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            startActivity(new Intent(CartActivity.this, MainActivity.class));
        }
    });
}