comparison of two Strings doesn't work in android

here's my code, Eclipse doesn't show any errors, program's working fine, but it simply doesn't do exactly what i want:)

    View image_view_danger_rate = (ImageView) findViewById(R.id.origin);
    View image_view_origin = (ImageView) findViewById(R.id.danger_rate);

    String entry_tag = (String) descriptionResultView.findViewById(resID).getTag();

    String dangerous = "dangerous";
    String not_dangerous = "not_dangerous";

    if ( entry_tag == dangerous) {
        image_view_danger_rate.setBackgroundResource(R.drawable.attention);
    }else if ( entry_tag == not_dangerous) {
        image_view_danger_rate.setBackgroundResource(R.drawable.its_ok);
        image_view_origin.setBackgroundResource(R.drawable.artificial);
    }

The application should choose between two images to pop-up on the screen, depending on a tag stored in the xml file. So, if the tag says "dangerous", then should be shown the "attention"-image. If the tag says "not_dangerous", there should be the "its_ok"-image.

Now, displaying the images without an if-comparison works perfectly.

If i print out the tags as a string, it works, it prints correctly "dangerous" or "not_dangerous", depending on the tag.

But if there's a if-comparison as shown above, nothing happens, no image is shown.

Please anyone help!!=)