我不知道您发布的错误，正确或输入错误，但根据您的代码，应该是

I don't know that you posted wrong or right or typing mistake but according to your code it should be

 ImageView image = new ImageView(activity_main,this);

到

 ImageView image = new ImageView(activity_main.this);

您也可以使用

 image.setImageResource(R.drawable.element_wall);

代替

 image.setBackgroundResource(R.drawable.element_wall);