一,通过判断输入值长度是否为零
String serch_textip=mEdit1.getText().toString().trim();
if(serch_textip.length()==0) //判断IP输入框是否为空
{Toast.makeText(MainActivity.this,"请输入ip", Toast.LENGTH_LONG).show();}
二,比较输入值是否为Empty
String serch_textip=mEdit1.getText().toString().trim();
if(serch_textip.isEmpty()) //判断IP输入框是否为空
{Toast.makeText(MainActivity.this,"请输入IP", Toast.LENGTH_LONG).show();}
三,比较输入值是否为null或者“ ”
String serch_textinfo =mEdit.getText().toString();
if(null == serch_textinfo || "".equals(serch_textinfo))
{Toast.makeText(this,"请输入Info", Toast.LENGTH_LONG).show();} //判断Info输入框是否为空