无法克隆<template>附加到<div>

Question

I create this template successfully with javascript:

I create the template in an async function:

this.createBoxes = async function() {
    var row_counter = 0;
    for (var i = 1; i < this.fake_data.length + 1; i++) {

        var item_box = document.createElement("div");
        item_box.style.flex = "0.5";
        item_box.style.backgroundColor = "white";
        item_box.style.display = "flex";
        item_box.style.flexDirection = "column";
        item_box.style.justifyContent = "flex-end";
        item_box.id = "item_box_"+i;

        var item_name = document.createElement("h3");
        item_name.style.flex = "0.2";
        item_name.style.backgroundColor = "orange";
        item_name.style.alignSelf = "center";
        item_name.innerText = this.fake_data[i - 1].name;
        item_name.id = "item_name_"+i;

        item_box.appendChild(item_name);

        this_row = document.getElementsByClassName("row")[row_counter];
        this_row.appendChild(item_box);

        if(i % 2 == 0) {
            var pool = document.getElementById("pool");
            var inner_row = document.createElement("div");
            inner_row.style.display = "flex";
            inner_row.style.flexDirection = "row";
            inner_row.style.flex = "0.5";
            inner_row.style.justifyContent = "space-around";
            inner_row.style.alignItems = "center";
            inner_row.style.backgroundColor = "green";
            inner_row.className = "row";

            pool.appendChild(inner_row);

            row_counter++;
        }
        else if(i == this.fake_data.length) {
            return;
        }
    }
}

Then I do this:

    this.createBoxes().then(function() {
        var template = document.querySelector('#pool');
        var clone = template.content.cloneNode(true);
        document.querySelector(".app").appendChild(clone);
    })

But as you can see from my screenshot, .app is empty. What am I doing wrong? I am using Cordova and I am assuming that it is able to use the template tag, I haven't been able to find anything saying I can't.

UPDATE

This happens:

When I do this:

    this.createBoxes().then(function() {
        var template = document.querySelector('#pool');
        var clone = template.cloneNode(true);
        document.querySelector(".app").appendChild(clone);
    });

Using template.cloneNode successfully moves the <template> but this is obviously not what I want, I want to get the contents of the <template> and move them to .app container, not the whole <template> .

Answer 1

Well, if cloning the node itself works, then the answer is pretty simple - just clone/append children of the template:

this.createBoxes().then(function() {
    let template = document.querySelector('#pool');
    let app = document.querySelector(".app");
    for(let child of template.childNodes) {
        let clone = child.cloneNode(true);
        app.appendChild(clone);
    }
});

Note that I have not tested this code - you may need to debug it as necessary.

Answer 2

I added a container to the template programmatically:

    var pool = document.getElementById("pool");

    var container = document.createElement("div");
    container.style.flex = "1";
    container.style.backgroundColor = "white";
    container.style.display = "flex";
    container.style.flexDirection = "column";
    container.id = "container";

    var row = document.createElement("div");
    row.style.display = "flex";
    row.style.flexDirection = "row";
    row.style.flex = "0.5";
    row.style.justifyContent = "space-around";
    row.style.alignItems = "center";
    row.style.backgroundColor = "green";
    row.className = "row";

    container.appendChild(row);
    pool.appendChild(container); 

Then instead of adding my content to the #pool <template> , I added it to #container , and then stored the #container node in a variable, and then imported that into .app :

var container_in_temp = document.querySelector('#pool>#container');
var targetContainer = document.querySelector('.app');
targetContainer.appendChild(document.importNode(container_in_temp, true));

So it ends up looking like this, with a container in .app which is actually kind of preferable structure wise :).

Answer 3

You should be cloning the template's .content instead, as demonstrated in the documentation .

  var temp = document.getElementsByTagName("template")[0];
  var clon = temp.content.cloneNode(true);
  document.body.appendChild(clon);