在TextWatcher mEditTextChangeListener监听中afterTextChanged这个方法里添加以下代码
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT)lp.width = LinearLayout.LayoutParams.MATCH_PARENT;
lp.height = editText.getLineHeight() * edittext .getLineCount();
//注意：这里要用editText.getLineHeight()这个，LinearLayout.LayoutParams.WRAP_CONTENT这个会获取不到高度
editText.setLayoutParams(lp);