Why Shared Preferences can't deal with my String?

Question

I'm using shared preferences to store some images thumbnails, these thumbnails are like the following :

"image:\/\/http%3a%2f%2fimage.tmdb.org%2ft%2fp%2foriginal%2fwBtEVh8Q5dglfjyulGZtgXVy9qi.jpg\/"

and :

"image:\/\/http%3a%2f%2fimage.tmdb.org%2ft%2fp%2foriginal%2fojgf8iJpS4VX6jJfWGLpuEx0wm.jpg\/"

I found that when put some regular Strings into it it works efficiently and I can get it without any problems(that makes me make sure that my code doesn't have any problems), but when putting these thumbnails and trying to get it back it can't find it. So, is there's some String formats that the SharedPreferences don't take?

And this is my code(if needed):

to put :

SharedPreferences sharedPreferences = PreferenceManager
                    .getDefaultSharedPreferences(this);

Editor editor = sharedPreferences.edit();
editor.putString(thumbnail, "some string");
editor.commit();

to get:

String  def_value = sharedPreferences.getString(thumbnail, "value");

Are you sure it doesn't have something to do with how you are escaping the characters in that string? — Rudi Kershaw, Mar 23 '14 at 12:18
Try printing the string value in Log.d() before you store it to check what the value is showing as when printed. That will also make sure it's not null as Aashish suggests. — Rudi Kershaw, Mar 23 '14 at 12:22

score 1 · Answer 1 · edited May 23 '17 at 11:44

Try with this (from this):

To put:

 // provide the app package name
   SharedPreferences prefs = this.getSharedPreferences(
      "com.example.app", Context.MODE_PRIVATE);
 Editor editor = sharedPreferences.edit();
 editor.putString("thumbnail", "some string");
 editor.commit();

To GET:

SharedPreferences sharedPreferences = getSharedPreferences("com.example.app", Activity.MODE_PRIVATE);
String  def_value = sharedPreferences.getString("thumbnail", "value");

Rudi Kershaw · Accepted Answer · 2014-03-23T12:43:41.037

In Java any character preceeded by a \ is considered an escape character. For example \n is the escape character representing a new line. In the following string;

"image:\/\/http%3a%2f%2fimage.tmdb.org%2ft%2fp%2foriginal%2fojgf8iJpS4VX6jJfWGLpuEx0wm.jpg\/"

The \/ is an illegal escape character (ie, it doesn't mean anything). So, if you really wanted those two character together what you need is the escape character for back slash (\\) followed by a forward slash, which would look like \\/.

Given that your strings look like urls, I imagine what you are actually looking for doesn't require escape characters at all, and could just look like this.

"image://http%3a%2f%2fimage.tmdb.org%2ft%2fp%2foriginal%2fojgf8iJpS4VX6jJfWGLpuEx0wm.jpg/"

well, I used your solution but with another way, I changed my String by using like `substring` with the retrieved thumbnail in order to escape unnecessary characters and that works — MRefaat, Mar 23 '14 at 12:42

Why Shared Preferences can't deal with my String?

2 Answers2