Nextion button

Hello .
I created a code for a led strip , blinking , and i want to stop the blink whenever i press the button Stop , the s button on the code . Can you help me ? What i need to put inside the do-while for making the blinking stop.
Thanks.

#include <Nextion.h>
#include <NexButton.h>

NexButton s = NexButton(10 , 8 , "S");
NexButton br = NexButton(10 , 2 , "R");
NexTouch *nex_listen_list[] =
{
&s,
&br
};
void brPushCallback(void *ptr)
{

pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
do
{
digitalWrite(5, HIGH);
digitalWrite(6, LOW);
digitalWrite(7, LOW);
delay(450);
digitalWrite(5, LOW);
delay(450);

} while(...);
digitalWrite(5, LOW);
digitalWrite(6, LOW);
digitalWrite(7, LOW);
}
void sPushCallback(void *ptr)
{
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
digitalWrite(5, LOW);
digitalWrite(6, LOW);
digitalWrite(7, LOW);
}
void setup() {
// put your setup code here, to run once:
nexInit();
Serial.begin(9600);

s.attachPush(sPushCallback , &s);

br.attachPush(brPushCallback, &br);
}

void loop() {
// put your main code here, to run repeatedly:

nexLoop(nex_listen_list);
}

This seems suspiciously similar to your original post:
http://forum.arduino.cc/index.php?topic=489279

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