How to Add a Button Click Event in Android Studio

How do I implement a button click event in Android Studio?

private Button btnClick;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    btnClick = (Button) findViewById(R.id.button);
    btnClick.setOnClickListener(this); // Setting click listener
}

To implement a button click event in Android Studio, ensure that the containing class implements the `View.OnClickListener` interface and overrides the `onClick` method. This allows you to define the actions that should occur when the button is clicked.

public class MainActivity extends AppCompatActivity implements View.OnClickListener { 
    private Button btnClick;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btnClick = findViewById(R.id.button);
        btnClick.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        // Handle button click event here
    }
}

Causes

• The containing class does not implement `View.OnClickListener` interface.
• Incorrect invocation of `setOnClickListener(this);` due to context misalignment.

Solutions

• Make sure your class extends `AppCompatActivity` or a related Activity class.
• Implement the `View.OnClickListener` interface in your `MainActivity` class.
• Override the `onClick(View v)` method to handle button clicks.

Mistake: Failing to implement `View.OnClickListener` interface, resulting in a type mismatch.

Solution: Add 'implements View.OnClickListener' to your class definition.

Mistake: Incorrect use of `equals()` method to compare string values.

Solution: Use `getText().toString().isEmpty()` to check if `EditText` fields are empty.