如何在android studio中点击按钮时从另一个活动更改textview文本？

Question

I have seen a lot of tutorials that gives answer for this, but I don't get it. It isn't working. I have a button in MainActivity , that has click listener that does this:

 Intent i = new Intent(MainActivity.this, DetailsActivity.class);
     i.putExtra("Name", "RESULT");
     startActivity(i);

Another actiivty:

txtview = (TextView) find.....(R.id.textView1);
Intent i = getIntent();
String str = i.getStringExtra("Name");
txtview.setText(str);

I don't use an emulator, I build the apk and then transfer it to my mobile. So in my mobile when I click the button, it closes and says "The app is not responding" XML:

<TextView
    android:text="result"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="145dp"
    android:id="@+id/txt" />

Answer 1

Change your TextView id to textView1.

findViewById method is returning null beacause there is no TextView with id textView1