为什么我的按钮在Android Studio中不起作用？

Question

I am doing A Level computing and I'm trying to make an app for my Comp 4 project. All the other classes i have done with buttons seem to be working fine but the buttons on my main menu are not working.

public class MainActivity extends AppCompatActivity {

Button bLogin;
Button bProducts;
EditText etName, etAge, etUsername;

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

@Override
protected void onStart() {
    super.onStart();
}

@Override
public boolean onCreateOptionsMenu (Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id= item.getItemId();
    switch (id) {
    case R.id.bLogin:
        break;
    case R.id.bProducts:
        break;
    }
    return super.onOptionsItemSelected(item);
}

public void ProductsOnClick(View b) {
    startActivity(new Intent(".Products"));
    switch (b.getId()) {
    case R.id.bProducts:
    }
}

public void LoginOnClick(View a) {
    startActivity(new Intent(".Login"));
    switch (a.getId()){
    case R.id.bLogin:
    }
}

}

This Activity runs but the buttons on the Options Menu don't work.

I am using Android Studio to program this.

Answer 1

Because there is nothing to execute when the menu item is selected, change your code like that:

 @Override
    public boolean onOptionsItemSelected(MenuItem item){
         int id= item.getItemId();
         switch (id) {
             case R.id.bLogin:
               startActivity(new Intent(".Login"));
             break;

             case R.id.bProducts:
               startActivity(new Intent(".Products"));
             break;
         }
         return super.onOptionsItemSelected(item);
}

---

PS:

Make sure that you're using the right Intent constructor, because with Intent(String) you need an action as parameter not an activity name or something else.

Answer 2

You can use OnClickListener instead. Put this in your onCreate :

bProducts.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        startActivity(new Intent(".Products"));
    }
});

bLogin.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        startActivity(new Intent(".Login"));
    }
});