How to display a text or graphics without flicker on the TFT LCD

[aaronchih]

I'm building a new device with 1.44" TFT LCD and ATMEGA328.
I'm using this library.
There are several features like a logo, a button image, and a graph.
But I have an issue when text or line display on the TFT LCD.
After displaying, and then, refresh and overwrite a text or graph.
In this time, there is blinking on the screen, so text and graph are flickering.
How can I display statically text and graph without flicker?

`if (count >= 100)
{
for (uint8_t x = 20; x < 120; x++)
{
tft.drawPixel(x, vol_1[x - 20] * 1 / 5, TFT_BLACK);
}
uint16_t tmp[99];
memcpy(tmp, &vol_1[1], sizeof(uint16_t) * 99);
memcpy(vol_1, tmp, sizeof(uint16_t) * 99);
vol_1[99] = voltage1 / 10;
}
else {
vol_1[count] = voltage1 / 10;
count++;
}

for (int16_t y = 0; y < tft.height(); y += 10) {
tft.drawFastHLine(0, y, tft.width(), color1);
}
for (int16_t x = 0; x < tft.width(); x += 10) {
tft.drawFastVLine(x, 0, tft.height(), color2);
}
for (uint8_t x = 20; x < 120; x++)
{
tft.drawPixel(x, vol_1[x - 20] * 1 / 5, TFT_GREEN);
}`