Question

I’m trying to make a check box to show/hide a HTML element, but I am trying to make it as efficient as possible (recycling one function and enabling it to evolve, rather than manually and statically writing unique functions).

I have already succeeded at this once, but in a slightly different scenario (included: “JavaScript Extract – Working Recycled Function”) but cannot get it to work in this new scenario (included: “JavaScript Extract – Not Working Recycled Function). I have scavenged what I can from it but I am having difficultly this time around. My brain has kinda ground to a halt after a couple of hours to solving other problems. I have multiple elements waiting to also use this, but for now I’m just trying to get it to work with the Google element first.

HTML Extract

<div id="googleContainer">
    <input type="text" id="googleSearchBox" title="Google Search" class="searchBox" />
    <input type="button" id="googleSearchButton" onClick="execSearchWithClick(this.id)" />
</div>
<input type="checkbox" id="googleCheck" checked="checked" onClick="setPref(this.id)"/>

JavaScript Extract – Working Recycled Function

var googleHome = "http://www.google.com/"; //Set home page
var googleSearchURL = googleHome + "search?q="; //Prime search URL
function execSearchWithClick(id){
    alert(id) //Check ID
    var searchBox = document.getElementById(id.replace("Button", "Box")); //Convert "googleSearchButton" to "googleSearchBox" to match target element
    var searchQuery = searchBox.value; //Extract value from converted string-to-variable

    if (searchQuery == ""){
        if (id == "googleSearchButton") {
            window.open(googleHome);
        } //I would use "if(condition && condition)" rather than nested IFs here, but I plan to use ELSE IF very soon
    } else {
        if (id == "googleSearchButton") {
            window.open(googleSearchURL + searchQuery);
        } 
    }
}

JavaScript Extract – Not Working Recycled Function

var googleDisplay = true;
function setPref(id){
    alert(id) //Check ID
    var checkboxDisplayString = document.getElementById(id.replace("Check", "Display")); //Convert "googleCheck" to "googleDisplay" to match boolean variable
    alert(checkboxDisplayString) //Null value reply
    var checkboxDisplayVar = checkboxDisplayString //Convert (what I suspect to be) String to variable name
    alert(checkboxDisplayVar) //Null value reply

    if (id == "googleCheck" && checkboxDisplayVar == true){
        checkboxDisplayVar = false;
        applyPref();
    } else {
        checkboxDisplayVar = true;
        applyPref();
    }
}

function applyPref(){
    if (googleDisplay == true){
        document.getElementById("googleContainer").style.display = "block";
    } else {
        document.getElementById("googleContainer").style.display = "none";
    }
}

EDIT: I’ve added much more detail for those who asked now. Sorry if everything has become more confusing.

Answer 1

This would be my attempt:

    function setPref(id){
        var checkbox = document.getElementById(id);
        applyPref(checkbox.checked);      
    }

    function applyPref(show){
        if (show){
            document.getElementById("googleContainer").style.display = "block";
        } else {
            document.getElementById("googleContainer").style.display = "none";
        }
    }

I may be missing something, but I think that something like the above should work