Androidstudio pulls this in an attempt to open MaterialDialog in OnClick.

[Anderson]

What's the mistake (this) in the code

button2.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
         new MaterialDialog.Builder(this)
                .title(R.string.app_name)
                .show();
    }
});

Screen:

[carriann]

MaterialDialog Builder https://github.com/afollestad/material-dialogs/blob/master/core/src/main/java/com/afollestad/materialdialogs/MaterialDialog.java#L476 ♪

You. this - reference to anonymous class OnClickListener♪

For example:

new MaterialDialog.Builder(НазваниеВашегоActivity.this){...}