Newly printed value overlaps the old value instead of replacing it. ESP32

[jelteliekens]

I'm connecting a SSD1283A display to an ESP32 Dev Kit (DOIT ESP32 DEVKIT V1). On the display I want to print a sensor value on screen every 3 seconds but instead of replacing the old printed text, it is overlapping the old value.

Should I be clearing the display first or flush the changes at the end of the loop? I did not see it in any examples so I don't think it is necessary.

Does somebody know what I'm doing wrong?

#include <Arduino.h>
#include <Arduino_GFX_Library.h>

// Millis
u_long previousMillis = 0;
uint16_t interval = 3000;

// Display
#define GFX_BL DF_GFX_BL

Arduino_DataBus *bus = new Arduino_ESP32SPI(27 /* DC */, 5 /* CS */, 18 /* SCK */, 23 /* MOSI */, GFX_NOT_DEFINED /* MISO */, VSPI /* spi_num */);
Arduino_GFX *gfx = new Arduino_SSD1283A(bus, 33 /* RST */);

// Pressure sensor
const int pressureSensorPin = 15;

void setup()
{
  // Setup serial monitor
  Serial.begin(115200);

  // Setup display
#ifdef GFX_BL
  pinMode(GFX_BL, OUTPUT);
  digitalWrite(GFX_BL, HIGH);
#endif

  gfx->begin();
  gfx->fillScreen(BLACK);
  gfx->setTextColor(WHITE);
}

void loop()
{
  u_long currentMillis = millis();

  if (currentMillis - previousMillis >= interval)
  {
    // Set previous millis
    previousMillis = currentMillis;

    // Read pressure sensor value
    uint16_t analogValue = analogRead(pressureSensorPin);

    // Update display
    gfx->setCursor(0, 0);

    gfx->print("Analog: ");
    gfx->println(analogValue); // This value will be overlapping it's previous value 
  }
}

[moononournation]

The default text background color is transparent. I you case you need set a solid background, e.g.:gfx->setTextColor(WHITE, BLACK);

[jelteliekens]

Oh great, this solves it! Thank you very much!