Hey,

i tried to reproduce this behaviour, but for me it works fine on Leopard and Lion with processing 1.5.1 and 2.0b3.
Could you post an example-code, where the issue occurs?

Yep, should have to begin with!  Also, it appears that I didn't update Processing 2.0 to the most recent version - running 2.0a6 the method for selectInput() returns a string, but the code doesn't work at all in 2.0b.

1. void setup() {
   
2.   size(500, 500);
   
3.   smooth();
   
4.   textAlign(CENTER, CENTER);
   
5. }
   
6. 
   
7. // in the draw, just display some instructions until a key is pressed
   
8. void draw() {
   
9.   background(0);
   
10.   fill(255);
    
11.   text("o  =  open file\ns  =  save file", width/2, height/2);
    
12. }
    
13. 
    
14. // letter 'o' opens file, 's' saves it
    
15. void keyPressed() {
    
16.   if (key == 'o') {
    
17.     openFile();
    
18.   }
    
19.   else if (key == 's') {
    
20.     saveFile();
    
21.   }
    
22. }
    
23. 
    
24. void openFile() {
    
25. 
    
26.   // load the full path to the file
    
27.   String inputFilename = selectInput("Select a file to open:");
    
28. 
    
29.   // if the load was successful, print the filename
    
30.   if (inputFilename != null) {
    
31.     println("File selected: " + inputFilename);    // let us know what happened
    
32.   }
    
33. 
    
34.   // if the user cancels we would normally do nothing at all...
    
35.   else {
    
36.     println("User did not select a file...");
    
37.   }
    
38. }
    
39. 
    
40. void saveFile() {
    
41. 
    
42.   // create a new complete path
    
43.   String outputFilename = selectOutput("Save As...");
    
44. 
    
45.   // if we've created a valid filename and path...
    
46.   if (outputFilename != null) {
    
47.     println("Saving to: " + outputFilename);
    
48.   }
    
49. 
    
50.   // if the save was canceled, we would normally do nothing...
    
51.   else {
    
52.     println("Save canceled...");
    
53.   }
    
54. }
    

Ok, now i see what you mean, i could reproduce it in 1.5.1
I can't explain why this happens, but you can avoid it by calling "noLoop()" before using "selectInput()", and "loop()" after.

1.   noLoop();
     String inputFilename = selectInput("Select a file to open:");
     loop();
   

The selectInput() in newer processing versions now uses a callback-function, an example of how to use it, is in the release-notes here.

FYI, the sketch works fine in 1.5.1 with Windows 7.

@PhiLho:
Hmm, Windows.  Perhaps it's an enter vs return thing?

@benja:
Your method seems to work, but the callback version in the release notes seems better.  The example isn't very clear, and the docs are less so.  Eventually, I realized that the callback argument isn't a string, but rather a string that is the same name as the function to handle the open/save.  I ended up with this:

1. File f;
   
2. 
   
3. void setup() {
   
4.   size(300,300);
   
5.   smooth();
   
6.   textAlign(LEFT, CENTER);
   
7. }
   
8. 
   
9. void draw() {
   
10.   background(0);
    
11.   fill(255);
    
12.   text("o  =  open a file\ns  =  save a file", 50, height/2);
    
13. }
    
14. 
    
15. void keyPressed() {
    
16.   if (key == 'o') {
    
17.     selectInput("Open...", "openFile");
    
18.   }
    
19.   else if (key == 's') {
    
20.     selectInput("Save As...", "writeFile");
    
21.   }
    
22. }
    
23. 
    
24. void openFile(File f) {
    
25.   if (f != null) {
    
26.     println("file: " + f.getAbsolutePath());
    
27.   }
    
28.   else {
    
29.     println("no file selected...");
    
30.   }
    
31. }
    
32. 
    
33. void writeFile(File f) {
    
34. 
    
35.   if (f != null) {
    
36.     println("saving: " + f.getAbsolutePath());
    
37.   }
    
38.   else {
    
39.     println("save file canceled...");
    
40.   }
    
41. }

I do prefer the File object being returned rather than a String, since I can do a lot more with it other than get the path.