Qt 将字符串转成16进制显示

struct UserData
{
    char Head[3] = {'X','J','J'};
    char Flag = '1'-'0x30';
    char X_Position = '1'-'0x30';
    char Y_Position = '@'-'0x30';
    char Sum = Head[0] + Head[1] + Head[2] + Flag + X_Position + Y_Position;
}userdata;

char temp[7];
temp[0] = userdata.Head[0];
temp[1] = userdata.Head[1];
temp[2] = userdata.Head[2];
temp[3] = userdata.Flag;
temp[4] = userdata.X_Position;
temp[5] = userdata.Y_Position;
temp[6] = userdata.Sum;
QString tt = temp;

QByteArray temp1 = tt.toLatin1().toHex();

QByteArray temp2;
for(int i = 0; i < temp1.length()/2;i++)
{
    temp2 += temp1.mid(i*2,2) + " ";
}