Letters only in Text box?

[Majed93]

Is there a way to only allow letters in ImGui::InputText?

[ocornut]

No but that could be added very easily following what ImGuiInputTextFlags_CharsHexadecimal is doing.

Flag definition in imgui.h

ImGuiInputTextFlags_CharsHexadecimal    = 1 << 1,   // Allow 0123456789ABCDEFabcdef

Code in imgui.cpp, InputTextFilterCharacter()

if (flags & ImGuiInputTextFlags_CharsHexadecimal)
    if (!(c >= '0' && c <= '9') && !(c >= 'a' && c <= 'f') && !(c >= 'A' && c <= 'F'))
        return true;

Would you like a-zA-Z only and not anything else?

[Majed93]

Yes just A-Z, also is there a way so it's only capital letters?

Thanks

[ocornut]

A-Z is a bit specific so I have added a character filtering system so you can filter characters yourself.

// turn input into uppercase
ImGui::InputText("uppercase", buf, 64, ImGuiInputTextFlags_CharsUppercase);

// custom filter, e.g:remove space
static int FilterNoSpace(ImGuiTextEditCallbackData* data)
{ 
    if (data->EventChar == ' ')  return 1;
    return 0;
}

ImGui::InputText("custom: no spaces", buf5, 64, ImGuiInputTextFlags_CallbackCharFilter, FilterNoSpace);

[ocornut]

Here's a callback function that does the filtering you want

                static int FilterAZ(ImGuiTextEditCallbackData* data) 
                { 
                    ImWchar c = data->EventChar;
                    if (!((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
                        return 1;
                    data->EventChar += 'A'-'a';
                    return 0;
                } 

[Majed93]

Got it working now! Thank you so much! :)

[Majed93]

Just noticed a little bug. We you put cap locks on and type letters, they are outputted as numbers or symbols.

[ocornut]

Yes sorry the function i wrote above wasn't tested and its wrong. Just increment the character if its a lowercase.

[ocornut]

e.g. (sorry it's hard typing code in the github box)

static int FilterAZ(ImGuiTextEditCallbackData* data) 
{ 
    ImWchar c = data->EventChar;
    if (c >= 'A' && c <= 'Z') return 0;
    if (c >= 'a' && c <= 'z') { data->EventChar += 'A'-'a'; return 0; }
    return 1;
}