android怎么实现代码高量EditText

dm = new DisplayMetrics();
getActivity().getWindowManager().getDefaultDisplay().getMetrics(dm);
edit_params = new LinearLayout.LayoutParams(
LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
edit_params.bottomMargin=8;
setEtContentHeight();
edit_problem_reson_send_msg_content.setLayoutParams(edit_params);

private void setEtContentHeight(){
if(edit_problem_reson_send_msg_content.getHeight()==dm.widthPixels /4){
edit_params.height=LayoutParams.WRAP_CONTENT;
}else{
edit_params.height=dm.widthPixels /4;
}
}