Null pointer exception when calling setOnClickListener()

Question

I am confused by this error:

java.lang.NullPointerException: Attempt to invoke virtual method `void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)` on a null object reference
        at 

    com.example.myapplication.MainActivity.onCreate(MainActivity.kt:20)

It says that this is the problem: Mainactivity.kt:

package com.example.myapplication

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        setSupportActionBar(toolbar)

        goToAddProduct.setOnClickListener {
            startActivity(Intent(this,AddProductActivity::class.java))
        }
    }
}

What is the problem?

Add the logcat error and activity and xml code , to investigate it further — Ravi, Apr 13 '20 at 07:36
You need to initialize `goToAddProduct` on which you are setting click listener. — Rajen Raiyarela, Apr 13 '20 at 07:41

score 0 · Answer 1 · answered Apr 13 '20 at 07:43

0

Use the following

Button goToAddProduct = findViewById(R.id.id_of_product_in_xml);

and then use the onclick like this

goToAddProduct.setOnClickListener {
        startActivity(Intent(this,AddProductActivity::class.java))
    }

answered Apr 13 '20 at 07:43

Ravi

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Kindly Upvote if answer was helpful to you – Ravi Apr 13 '20 at 08:22

Null pointer exception when calling setOnClickListener()

1 Answers1