javascript - 向上滚动文本并在使用 html5 音频读取文本时将其隐藏

Question

我正在使用代码来突出显示用 html5 音频读取的文本单词，并在单击相邻句子时也读取音频。

我需要的是让正在读取的行从页面中消失，并且正在读取的下一行跳转到它的位置，等等......所以到最后页面中什么都没有留下，但是:1-音频播放器，2-“突出显示开/关”按钮，3-“滚动开/关”按钮。

因此页面中有两个选项，用户希望在阅读时同时看到所有文本，或者只看到正在听到的行(以及它下面的行)。

正在使用的代码是:

var textHighlightOn = true,
    btnToggle = document.getElementById('toggleTxt'),
    textDiv   =  document.querySelector('.text-highlight')
    spns = document.querySelectorAll('span'),
    audi = document.getElementById("adi");

audi.addEventListener("timeupdate", f1);

function f1(){
  
  // remove all previous actives;
  [].forEach.call(spns, function(e){
      e.classList.remove('active');
      e.classList.remove('active-prev');
  });

  var i;  
  for (i = 0 ; i< spns.length ; i++){
     
    
  
    var time = Number(spns[i].id.slice(2));
    if(time < audi.currentTime){
      
       if (i>0) {
       
           spns[i-1].classList.remove('active');
           spns[i-1].classList.add('active-prev');
       
       }
       
       spns[i].classList.add('active');
      
    }
    
  }
}


// listen for clicks on the spans.
[].forEach.call(spns, function(spn) {

    spn.addEventListener("click", function() {
    
        for(var i in spns){
            
            

        }
        
        var time = Number(this.id.slice(2));
        audi.currentTime = time;
        
    });
    
});

// Toggle text highlight
btnToggle.addEventListener("click", function(){

    if(textHighlightOn){
       textDiv.classList.add('off');
    } else {
       textDiv.classList.remove('off');
    }

    this.innerHTML = 'Highlight ' + (textHighlightOn ? 'off ' : ' on');         

    textHighlightOn = !textHighlightOn;

});

body {
  background: #008000;
}
.text-highlight span.active-prev {
   background: #fff;
}
.text-highlight span.active {
   background: #03a9f4;
}
.text-highlight.off span {
   background: transparent;
}

<audio id="adi" controls>
  <source src="https://ia802508.us.archive.org/5/items/testmp3testfile/mpthreetest.mp3"/>
</audio>

<button id="toggleTxt">Highlight on</button>

<div class="text-highlight">
  <pre>
<span id="ts0.5">Ok, we're trying this for a second time</span> ,
<br><span id="ts3">to test the ability</span>
<br><span id="ts6">to upload an M P</span>
<br><span id="ts9">3 file.</span>
<br><span id="ts10">Hopefully this will work!</span>

    </pre>
</div>

Answer 1

这应该可以做到。

var 
// Controlls
textHighlightOn  = true,
showAllTxt       = true,
btnToggle        = document.getElementById('toggleTxt'),
btnToggleShowTxt = document.getElementById('toggleShowTxt'),
    
textDiv =  document.querySelector('.text-highlight'),
spns = document.querySelectorAll('span'),
audi = document.getElementById("adi");

audi.addEventListener("timeupdate", f1);

function f1(){
  
  // remove all previous actives;
  [].forEach.call(spns, function(e){
      e.classList.remove('active');
      e.classList.remove('active-prev');
  });

  var i;  
  for (i = 0 ; i< spns.length ; i++){
     
    var time = Number(spns[i].id.slice(2));
    if(time < audi.currentTime){
      
       if (i>0) {
       
           spns[i-1].classList.remove('active');
           spns[i-1].classList.add('active-prev');
       
       }
       
       spns[i].classList.add('active');
      
    }
    
  }
}


// listen for clicks on the spans.
[].forEach.call(spns, function(spn) {

    spn.addEventListener("click", function() {
    
        for(var i in spns){
            
            

        }
        
        var time = Number(this.id.slice(2));
        audi.currentTime = time;
        
    });
    
});

// Toggle text highlight
btnToggle.addEventListener("click", function(){

    if(textHighlightOn){
       textDiv.classList.add('off');
    } else {
       textDiv.classList.remove('off');
    }

    this.innerHTML = 'Highlight ' + (textHighlightOn ? 'off ' : ' on');         

    textHighlightOn = !textHighlightOn;

});


// 
btnToggleShowTxt.addEventListener("click", function(){

    if(showAllTxt){
       textDiv.classList.remove('show-all');
    } else {
       textDiv.classList.add('show-all');
    }

    this.innerHTML = 'See All Text ' + (showAllTxt ? 'off ' : ' on');         

    showAllTxt = !showAllTxt;

});

body {
  background: #008000;
}
span {
   padding:0;
   margin:0;
}

.text-highlight span {
   display:block;
   margin-bottom:1px;
}

.text-highlight span.active-prev {
   display:none;
   background:#fff;
}
.text-highlight span.active {
   background: #03a9f4;
   display:block;
}
.text-highlight.show-all span {
   display:block !important;  
}


/* turn off highlight */
.text-highlight.off span {
   background: transparent;
}

<audio id="adi" controls>
  <source src="https://ia802508.us.archive.org/5/items/testmp3testfile/mpthreetest.mp3"/>
</audio>

<button id="toggleTxt">Highlight on</button>
<button id="toggleShowTxt">See All Text on</button>

<div class="text-highlight show-all">
   <span id="ts0.5">Ok, we're trying this for a second time,</span>
   <span id="ts3">to test the ability</span>
   <span id="ts6">to upload an M P</span>
   <span id="ts9">3 file.</span>
   <span id="ts10">Hopefully this will work!</span>
</div>