How To Set Navigationicon On Toolbar ("java.lang.classcastexception" Error)

I want to have a back button on my toolBar, but I am stuck with this error: java.lang.ClassCastException: androidx.appcompat.widget.Toolbar cannot be cast to android.widget.Too

Solution 1:

You have to import in your code:

import androidx.appcompat.widget.Toolbar;

instead of android.widget.Toolbar

Also remove the casting:

//Toolbar mToolbar = (android.widget.Toolbar) findViewById(R.id.toolbar);ToolbarmToolbar= findViewById(R.id.toolbar);