raylib/examples/text/text_input_box.c
Francisco Javier Andrés Casas Barrientos 4dd5643402
Added missing null terminator (#1820)
Added missing null terminator when adding characters to the string, otherwise garbage values are read (often zeros which are equal to '\0', but not every time).

This error results in random characters appearing in the text box every one in a while:
```
asdfg??? ll??
```
It is corrected with the proposed fix.

This problem was observed by my student, Gonzalo Rivera Lazo.
2021-06-10 20:24:08 +02:00

128 lines
4.5 KiB
C

/*******************************************************************************************
*
* raylib [text] example - Input Box
*
* This example has been created using raylib 3.5 (www.raylib.com)
* raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
*
* Copyright (c) 2017 Ramon Santamaria (@raysan5)
*
********************************************************************************************/
#include "raylib.h"
#define MAX_INPUT_CHARS 9
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
const int screenWidth = 800;
const int screenHeight = 450;
InitWindow(screenWidth, screenHeight, "raylib [text] example - input box");
char name[MAX_INPUT_CHARS + 1] = "\0"; // NOTE: One extra space required for null terminator char '\0'
int letterCount = 0;
Rectangle textBox = { screenWidth/2 - 100, 180, 225, 50 };
bool mouseOnText = false;
int framesCounter = 0;
SetTargetFPS(10); // Set our game to run at 10 frames-per-second
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
if (CheckCollisionPointRec(GetMousePosition(), textBox)) mouseOnText = true;
else mouseOnText = false;
if (mouseOnText)
{
// Set the window's cursor to the I-Beam
SetMouseCursor(MOUSE_CURSOR_IBEAM);
// Get char pressed (unicode character) on the queue
int key = GetCharPressed();
// Check if more characters have been pressed on the same frame
while (key > 0)
{
// NOTE: Only allow keys in range [32..125]
if ((key >= 32) && (key <= 125) && (letterCount < MAX_INPUT_CHARS))
{
name[letterCount] = (char)key;
name[letterCount+1] = '\0'; // Add null terminator at the end of the string.
letterCount++;
}
key = GetCharPressed(); // Check next character in the queue
}
if (IsKeyPressed(KEY_BACKSPACE))
{
letterCount--;
if (letterCount < 0) letterCount = 0;
name[letterCount] = '\0';
}
}
else SetMouseCursor(MOUSE_CURSOR_DEFAULT);
if (mouseOnText) framesCounter++;
else framesCounter = 0;
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(RAYWHITE);
DrawText("PLACE MOUSE OVER INPUT BOX!", 240, 140, 20, GRAY);
DrawRectangleRec(textBox, LIGHTGRAY);
if (mouseOnText) DrawRectangleLines(textBox.x, textBox.y, textBox.width, textBox.height, RED);
else DrawRectangleLines(textBox.x, textBox.y, textBox.width, textBox.height, DARKGRAY);
DrawText(name, textBox.x + 5, textBox.y + 8, 40, MAROON);
DrawText(TextFormat("INPUT CHARS: %i/%i", letterCount, MAX_INPUT_CHARS), 315, 250, 20, DARKGRAY);
if (mouseOnText)
{
if (letterCount < MAX_INPUT_CHARS)
{
// Draw blinking underscore char
if (((framesCounter/20)%2) == 0) DrawText("_", textBox.x + 8 + MeasureText(name, 40), textBox.y + 12, 40, MAROON);
}
else DrawText("Press BACKSPACE to delete chars...", 230, 300, 20, GRAY);
}
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}
// Check if any key is pressed
// NOTE: We limit keys check to keys between 32 (KEY_SPACE) and 126
bool IsAnyKeyPressed()
{
bool keyPressed = false;
int key = GetKeyPressed();
if ((key >= 32) && (key <= 126)) keyPressed = true;
return keyPressed;
}