How to prevent button from changing state after long press

How-to
1

Description

How to prevent button from changing state after long press?

What LVGL version are you using?

8.2 in combination with SquareLine Studio

What do you want to achieve?

A button which can be used to switch on and off a lamp. But when long pressed enable e.g. brightness control. But after the long press the button state should not change.

2

I have faced the same issue on my hardware TFT project with my custom board design from SquareLine studio project.

I have solved the issue by writing my own touch device call back function — touchpad_read() as below.

static void touchpad_read(lv_indev_drv_t *indev_drv, lv_indev_data_t data)
{
uint8_t touchpad_cnt = 0;
static uint8_t prvStat = LV_INDEV_STATE_RELEASED;
/Read touch controller is ready or not/
if (touch controller is ready)
{
/ Read data from touch controller */
if (touch found)
{
data->point.x = xdata;
data->point.y = ydata;
data->state = LV_INDEV_STATE_PRESSED;
prvStat = LV_INDEV_STATE_PRESSED;
}
else
{
data->state = LV_INDEV_STATE_RELEASED;
prvStat = LV_INDEV_STATE_RELEASED;
}
}
else{
//touch controller new data is not ready continue with previous state
data->state = prvStat;
}
}