javascript - setTimeout and recursive IFFEs, nested!? How to calculate the delay. -


this problem has reminded me regarding js skills... :(

i feel i'm right on cusp i'm struggling understand conceptually, it's not syntax issue feel cracked it.

what need

  • i'm trying console.log series of strings, 1 letter @ time.
  • there needs delay between each letter outputted, 300ms.
  • there must delay between each string outputted, 2000ms.
  • there 2 strings in example array, solution must support dynamic number of strings.

my current code (can pasted console)

var stringlist = ['first test','second test'],     stringlistlen = stringlist.length;        for(var = 0; < stringlistlen; i++){      // begin first string , read it's length iterations             var stringnumber = 0;     var currentstring = stringlist[stringnumber];     var currentstringlen = currentstring.length;      // see word clarification @ point in code     console.log(currentstring);       (function (i) {         settimeout(function () {                              (var j = 0; j < currentstringlen; j++) {                (function (j) {                 settimeout(function () {                      // magic happens here                     console.log(j, currentstring.charat(j));                      // end of string, read next string, reset letter count                     if(j === currentstringlen - 1){                         stringnumber++;                         currentstring = stringlist[stringnumber];                         j = 0;                                           }                  }, 300 * j); // each letter * specified delay               })(j);             };          }, currentstringlen * 300 * i); // letter * delay * letters in word     })(i);         }

the issue

the good: getting short delay between letters outputted, , check switch new word , reset letter counter when end of first word working...

the bad: can't wait between 2 words work. have tried few ideas , have got myself confused don't know if approach correct now.

the ugly: final letter of last term not outputting, , totally unexpected.

what i've tried.

okay, i've tried changing "currentstringlen * 300 * i" elements various combinations seemed logical had no effect better or worse. think trying calculate "wait number of letters in current string times 300 (the letter delay) * " <---- strikethrough...

i don't know i'm calculating , that's issue.

i think want split 2 functions, not 2 nested ones. 1 read , pass in string function outputs letters short delay, once gets last letter calls first function asking next word. i'm still going need recurse number of strings in array creates same issue...

am missing fundamental here people?

is had in mind?

function printletters(stringlist) {      var wordindex = 0,          letterindex = 0;        printnext();        function printnext() {          var word = stringlist[wordindex];          var letter = word.charat(letterindex);            console.log(letter);            ++letterindex;            if (letterindex === word.length) {              letterindex = 0;              ++wordindex;                if (wordindex < stringlist.length) {                  settimeout(printnext, 2000);              }                            return;          }            settimeout(printnext, 300);      }  }    printletters(['first test', 'second test']);

here there's ever 1 settimeout running @ once , new 1 being set required appropriate time.

while don't recommend having multiple timers running @ once, can done. this:

function printletters(stringlist) {      var lettercount = 0,          starttime = date.now();        stringlist.foreach(function(word, wordcount) {          word.split('').foreach(function(letter) {              settimeout(function() {                  console.log(letter, date.now() - starttime);              }, wordcount * 1700 + (lettercount * 300));                ++lettercount;          });      });  }    printletters(['first test', 'second test']);

here i've included time delta in logging give better sense of going on when. gap between strings 2000 constant in code 1700 because there's 300 being added.


Comments

Post a Comment

Popular posts from this blog

angular - Ionic slides - dynamically add slides before and after -

hi i'm using ngfor create set of 3 slides while starting in middle i'm guaranteed able slide left or right on start. when slide right can simple listen reachedend , push slide array i'm looping. but have problem adding slide beginning. if same above , use e.g. array.unshift() or spread add item beginning, view think it's on position 0 , snaps view new slide. the code below work animates slide change index 1. slide = [0,1,2] //example loop slidechanged(event) { if(this.slides.isbeginning()){ this.slide = [this.slide[0]-1, ...this.slide]; this.slides.update(); this.slides.slideto(1) } } <ion-slides [initialslide]="1" (ionslidedidchange)="slidechanged($event)"> <ion-slide *ngfor="let item of slide"> <h1>slide {{item}}</h1> </ion-slide> </ion-slides> any appreciated! you can using ionslidenextend , ionslideprevend events slides . please
Read more

minify - Minimizing css files -

i want know how css files can minimized. currently, using external sites css minifier compress css files. however, after removing whitespaces, comments, etc, file sizes reduced 10-15%. how frameworks bootstrap manage make minimized versions kilobytes. as example, css is: body { background-color: #ff0; } the reduction goes 28 bytes 22 bytes other css files have lot more characters still smaller this. actually minifying code means it's remove thing code white space characters new line characters comments block delimiters it reduces amount of code has transferred on web , speed site load fastly.but unreadable format.
Read more

Add a dynamic header in angular 2 http provider -

i have http interceptor built via tutorial https://scotch.io/@kashyapmukkamala/using-http-interceptor-with-angular2 the problem need have dynamic header changes automatically once changes 'mode' in app. service able tell interceptor change header, or have interceptor pull header (which string)from service each request. able throwing away patch method, call http.patch('new header string') set header string. call in service controls 'mode' setting. wondering if there way interceptor pull recent value service each request or if can add method http provider via interceptor? i've tried call service in interceptor each request returns undefined. because creating new instance of service or copying value before service fired , loaded/changed data. i don't want pass header string every http provider call because defeats purpose of having interceptor, id able set once changes or have provider fetch service before makes request. tl;dr : need add autom
Read more