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std::string += not working

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Join Date: Jun 2008

Posts: 408

Reputation: sciwizeh is on a distinguished road

Solved Threads: 22

sciwizeh

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Posting Pro in Training

std::string += not working

Apr 10th, 2009

Hello all, I'm trying to make a simple text box with SDL, I have loosely based it off of The Lazy Foo Tutorial on sting input, but this code doesn't seem to work...

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if(event.type==SDL_MOUSEBUTTONDOWN){
             if(isIn(event.button.x,event.button.y)){
                     hasFocus=true;
             } else {
                     hasFocus=false;
             }
     }
     if(event.type==SDL_KEYDOWN){
             if(hasFocus){
                     if(event.key.keysym.sym!=SDLK_BACKSPACE){
                             str+=(char)(event.key.keysym.unicode);
                     } else {
                             if(str.length()!=0){
                                       str.erase(str.length()-1);
                             }
                     }
             }
     }
if(event.type==SDL_MOUSEBUTTONDOWN){
             if(isIn(event.button.x,event.button.y)){
                     hasFocus=true;
             } else {
                     hasFocus=false;
             }
     }
     if(event.type==SDL_KEYDOWN){
             if(hasFocus){
                     if(event.key.keysym.sym!=SDLK_BACKSPACE){
                             str+=(char)(event.key.keysym.unicode);
                     } else {
                             if(str.length()!=0){
                                       str.erase(str.length()-1);
                             }
                     }
             }
     }

From a debug the focusing works fine, as is the display, but for some reason the character is not getting appended. What can I do to fix this?

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Join Date: May 2008

Posts: 374

Reputation: Clockowl is on a distinguished road

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Clockowl

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Re: std::string += not working

Apr 10th, 2009

Maybe make sure that conversion is going alright?

Output (char) (event.key.keysym.unicode) or something.

ASCII chars in UTF-8 might be something like, {\x00\x<ASCII-code>}, in that case, you're appending \x00

. It's my best guess.

Last edited by Clockowl; Apr 10th, 2009 at 6:22 pm.

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Join Date: Jun 2008

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Reputation: sciwizeh is on a distinguished road

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sciwizeh

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Re: std::string += not working

Apr 10th, 2009

Thanks for the reply, I'll check that out in a little bit, and post results.

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Join Date: May 2008

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Reputation: Clockowl is on a distinguished road

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Clockowl

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Re: std::string += not working

Apr 10th, 2009

From the reference:

"... The unicode field is only used when UNICODE translation is enabled with SDL_EnableUNICODE. ... "

I suppose you did that, but below there is code on how to translate that code back to ASCII.

Buuuuttt as he also notes, if you're not using unicode, don't enable it. Why not grab the .sym instead and convert that? Hope it helps anyway.

Last edited by Clockowl; Apr 10th, 2009 at 6:42 pm.