javascript - 如何为 Greasemonkey 脚本创建切换按钮？

Question

因此，我试图弄清楚如何为油脂猴扩展程序制作一个切换按钮，该扩展程序可以运行并导航到各个页面。

这就是我到目前为止所拥有的

var keepgoing = true

if 语句和此处内容的开头

else if keepgoing == true
  { newsearch(); }

点击按钮:

 if keepgoing == true { keepgoing = false }
 else if keepgoing == false { keepgoing = true }

所以基本上我需要帮助在网页上放置一个按钮。并且在浏览页面时需要记住 var。

谢谢，雷

Answer 1

如果您想要一个持久按钮(或任何数据)，您将需要使用某种存储。如果涉及多个域，则使用GM_setValue() 。如果所有内容都在同一域中，请使用 localStorage .

我自己添加了这种持久按钮，这是一个精简的脚本，显示了我使用的内容。在我看来，它不仅仅是添加一个按钮，它还使按钮 UI 更加用户友好。

注意:

1. 按钮状态在页面加载和网站之间保持不变。
2. 该按钮停留在左上角(由 CSS 设置)，当鼠标悬停在其上方时，该按钮会淡出至接近不透明的状态。
3. 我使用对象，因为有时我会向页面添加多个控件。
4. 您可以see a demo of how the button appears and behaves at jsFiddle 。 (除了演示中的值无法在页面加载过程中持续存在。它们在 GM 脚本中是这样的。)

// ==UserScript==
// @name     _Keep going button
// @include  http://YOUR_SERVER_1.COM/YOUR_PATH/*
// @include  http://YOUR_SERVER_2.COM/YOUR_PATH/*
// @require  http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js
// ==/UserScript==

//--- Add the button.
$("body").append (
      '<div class="gmPersistentButton">'
    + '<button id="gmContinueBtn">Init failed!</button></div>'
);

//--- Define and init the matching control object:
var btnControl  = new PersistentButton (
    "gmContinueBtn",        //-- HTML id
    "StopContinueBtn",      //-- Storage label
    ["Stop", "Continue"],   //-- Text that the button cycles through
    [false, true]           //-- Matching values for the button's states
);

//--- Activate the button click-handler.
$("#gmContinueBtn").click ( function () {
    var btnValue    = this.value;
    keepgoing       = btnValue
    btnControl.SetNextValue ();

    if (keepgoing == "true") {
        // CALL YOUR FUNCTION HERE.
    }
} );

//--- The button will fade when we aren't using it.
var zDisplayPanel   = $('div.gmPersistentButton');
zDisplayPanel.hover (
    function () { $(this).stop (true, false).fadeTo (50,  1  ); },
    function () { $(this).stop (true, false).fadeTo (900, 0.1); }
);
zDisplayPanel.fadeTo (2900, 0.1);


//--- CSS styles to make it work and to improve appearance.
GM_addStyle ( (<><![CDATA[
    .gmPersistentButton {
        background:         orange;
        color:              black;
        position:           fixed;
        top:                1em;
        right:              1em;
        z-index:            6666;
        padding:            1em;
        border:             3px double gray;
        border-radius:      1ex;
        opacity:            0.8;
    }
    .gmPersistentButton button {
        cursor:             pointer;
    }
    .gmPersistentButton button:hover {
        color:              red;
    }
]]></>).toString () );


//--- Button object
function PersistentButton (htmlID, setValName, textArry, valueArry) {
    //--- Initialize the button to last stored value or default.
    var buttonValue     = valueArry[0];
    fetchValue ();
    storeValue ();      //-- Store, in case it wasn't already.
    setButtonTextAndVal ();

    //--- DONE with init.  Set click and keyboard listeners externally.

    //***** Public functions:
    this.Reset          = function () {
        buttonValue     = valueArry[0];
        storeValue ();    
        setButtonTextAndVal ();
    };

    this.SetNextValue   = function () {
        var numValues   = valueArry.length;
        var valIndex    = 0;

        for (var J = numValues - 1;  J >= 0;  --J) {
            if (buttonValue == valueArry[J]) {
                valIndex    = J;
                break;
            }
        }
        valIndex++;
        if (valIndex >= numValues)
            valIndex    = 0;

        buttonValue     = valueArry[valIndex];

        storeValue ();    
        setButtonTextAndVal ();
    };


    //***** Private functions:
    function fetchValue () {
        buttonValue     = GM_getValue (setValName, buttonValue);
    }

    function storeValue () {
        GM_setValue (setValName, buttonValue);
    }

    function setButtonTextAndVal () {
        var buttonText  = "*ERROR!*";

        for (var J = valueArry.length - 1;  J >= 0;  --J) {
            if (buttonValue == valueArry[J]) {
                buttonText  = textArry[J];
                break;
            }
        }

        var theBtn      = document.getElementById (htmlID);
        if (theBtn) {
            theBtn.textContent  = buttonText;
            theBtn.setAttribute ("value", buttonValue);
        }
        else
            alert ('Missing persistent button with ID: ' + htmlID + '!');
    }
}