Nullpointerexception - while Passing data via intents

Question

I am having an issue where I can not sort out the NullPointerException (NPE) that I am getting.

Here is my MainActivity code

public void onActivityResult(int requestCode, int resultCode, Intent data) {
        IntentResult result = IntentIntegrator.parseActivityResult(requestCode, resultCode, data);
        String bccode = result.getContents();

        if(result != null) {
            if(result.getContents() == null) {
                Toast.makeText(this, "Cancelled", Toast.LENGTH_LONG).show();
            } else {
                Intent sendBarCode= new Intent(MainActivity.this, showdata.class);
                sendBarCode.putExtra("barccode", bccode);
                startActivity(sendBarCode);
                startActivity(new Intent(MainActivity.this, showdata.class));
            }
        } else {
            super.onActivityResult(requestCode, resultCode, data);

        }
 }

And my class that receives it showdata.class:

public String barcode = getIntent().getStringExtra("barccode"); 

The exact error:

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Intent.getStringExtra(java.lang.String)' on a null object reference

This particular NPE has me a bit perplexed as I have followed all the instructions I can find online.

Answer 1

Protect from NPE

final Intent intent = getIntent();
if (intent != null) {
   ...
}
else {
    Log.d(TAG, "No intent");
}

Answer 2

因此，您要两次调用startActivity ，一次是使用数据，一次是使用不会包含任何数据的新Intent 。

Answer 3

TRY This out in the showdata class.

public String barcode = null;
Intent i = getIntent();
barcode =i.getStringExtra("barccode");