Determines whether the input string consists of spaces, tabs, carriage returns, and line breaks.

 1 public class StringUtils 

2 {
3 /**
4 * determine whether the given string is a blank string. <Br>
5 * a blank string is a string consisting of spaces, tabs, carriage returns, and line breaks. <br>
6 * If the input string is null or a null String, true is returned.
7 * @ param input
8 * @ return boolean
9 */
10 public static boolean isBlank (String input)
11 {
12 if (input = null | "". equals (input ))
13 return true;
14
15 for (int I = 0; I <input. length (); I ++)
16 {
17 char c = input. charAt (I );
18 if (c! = ''& C! = '\ T' & c! = '\ R' & c! = '\ N ')
19 {
20 return false;
21}
22}
23 return true;
24}
25}

1 private boolean checkContent (){
2 boolean ret = true;
3 if (StringUtils. isBlank (content. getText (). toString ())){
4 Toast. makeText (mContext, "Please input your feedback. Thank you", Toast. LENGTH_SHORT). show ();
5 ret = false;
6}
7 return ret;
8}