使用焦點激活AppBar時顯示軟鍵盤，使內容跳回到頂部

Question

目前剛剛開始開發UWP WinJS應用程序，並在Windows 10移動版上進行了測試。

我有一個應用程序欄和一個內容可編輯的div-如果按應用欄上的按鈕以加粗內容區域中的某些單詞，則div會將其加粗，但在調用editor.focus（）時也將完全跳到頂部。 我希望它保持當前位置。

我想做的是即使在AppBar上按下按鈕時也要出現鍵盤。 （如果沒有editor.focus（），則在單擊按鈕時鍵盤會消失。）不幸的是，有了這些額外的代碼行，我遇到了上面的滾動問題。

<div id="editor" contenteditable="true">
    Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam tristique convallis aliquet. Proin ac urna ut diam luctus facilisis vel in ligula. Morbi porta volutpat est eget semper. Sed elementum tincidunt libero. Cras a felis leo. Fusce lacinia turpis vel turpis facilisis sollicitudin. Suspendisse blandit, nisi gravida fermentum placerat, velit ipsum volutpat mi, ut finibus enim mauris at massa. Etiam placerat et mi eget iaculis. Aliquam et semper nisl. Integer id magna non sapien tempus suscipit at eget sem. Integer quam risus, placerat sit amet iaculis ac, ultrices non diam. Aliquam at convallis velit, vitae iaculis lectus. Morbi non orci eget mi placerat aliquet. Sed at neque a eros efficitur egestas. Donec sed luctus leo, ac ullamcorper dui.

    Nullam volutpat ultricies leo, ut congue risus egestas euismod. Suspendisse nisi ligula, volutpat id tempor convallis, facilisis in justo. Nulla porta neque eget ante tincidunt pellentesque. Integer felis libero, rutrum eu interdum eu, finibus a felis. Vestibulum vel est dictum, tempor ex vel, facilisis lorem. Nulla facilisi. Nulla ut ornare tortor, vitae blandit augue. Quisque imperdiet pretium turpis, ac fermentum diam imperdiet vitae. Pellentesque vel mollis odio. Quisque tempus eget neque non pretium.

    Cras eu velit sit amet dolor pulvinar ultricies at id lectus. Suspendisse quis metus sem. Etiam lectus mauris, lobortis volutpat consectetur at, sodales in nisl. Fusce euismod magna in leo tempor, quis bibendum leo gravida. Nulla varius velit vel ultrices sollicitudin. Morbi at odio efficitur, iaculis odio ut, auctor mauris. Phasellus nec lacus arcu. Duis porttitor, urna sit amet tempor dapibus, velit libero malesuada erat, eget pulvinar velit quam id leo. Quisque vulputate vehicula ante, vel condimentum dui consectetur eget.

    Curabitur lobortis porta justo quis pulvinar. Aliquam quam nisl, aliquam vel risus et, semper molestie nulla. Aenean mollis facilisis odio vel convallis. Suspendisse vestibulum nec sapien ut pretium. Duis vehicula, mi sed rutrum luctus, odio magna hendrerit nisl, laoreet eleifend augue neque vestibulum dui. Proin vitae metus convallis, condimentum enim in, volutpat nisl. Aliquam at est id felis placerat fermentum. Duis suscipit commodo convallis. Aliquam imperdiet mollis tortor, sit amet placerat tellus malesuada in. Nunc fringilla sem lorem, nec efficitur purus lobortis mollis. Duis non eros aliquam, luctus libero sed, ullamcorper odio.

    Fusce orci est, rutrum non urna a, finibus suscipit dolor. Mauris suscipit mi ut dolor cursus, quis laoreet est porta. Etiam bibendum fringilla turpis et sagittis. Aenean vehicula maximus dui ut pretium. Vestibulum iaculis id sapien nec condimentum. Donec a aliquet enim. Donec non mauris convallis, tincidunt elit sit amet, ultrices nulla. Duis vel auctor nisl, vitae ultrices mi. Suspendisse potenti. Vivamus sit amet lacus urna. Fusce a sagittis risus. Cras facilisis porta purus, vitae scelerisque mauris vehicula eu. 
</div>

<div data-win-control="WinJS.UI.AppBar" id="appBar" data-win-options="{placement: 'bottom', sticky: 'true'}" style="background-color: #e6e6e6;">       
        <button  data-win-control="WinJS.UI.AppBarCommand" data-win-options="{id: 'boldBtn', icon: 'bold', section:'selection', tooltip:'bold'}"></button>
</div>

使用Javascript：

element.querySelector("#boldBtn").addEventListener("click", toggleBold, false);

function toggleBold() {
    document.execCommand('bold', false, null);
    editor.focus();   // this will cause the div to jump back to the top if it's not already at the top
}

使用tryShow（）嘗試了另一種解決方案，以檢測何時鍵盤將被隱藏。 一旦檢測到，請強制出現鍵盤。 另外，顯示AppBar（因為它消失了），將編輯器放在焦點上，然后滾動回到以前的位置。 這需要花費幾秒鍾的時間來完成，並且滾動效果太明顯了，因此不可行。

Answer 1

如果要將屏幕滾動到所選位置，則應計算坐標的offset ，該offset是由軟件鍵盤的顯示引起的。

這是我的Javascript代碼：

（function（）{“ use strict”;

var app = WinJS.Application;
var activation = Windows.ApplicationModel.Activation;

var userHeight, cursorY0, range;

app.onactivated = function (args) {
    if (args.detail.kind === activation.ActivationKind.launch) {
        if (args.detail.previousExecutionState !== activation.ApplicationExecutionState.terminated) {
            // TODO: This application has been newly launched. Initialize your application here.
        } else {
            // TODO: This application was suspended and then terminated.
            // To create a smooth user experience, restore application state here so that it looks like the app never stopped running.
        }
        args.setPromise(WinJS.UI.processAll().done(
            function () {



                //var editor = document.getElementById("editor");
                //editor.addEventListener("click", toggleBold, false);
                var button = document.getElementById("boldBtn");
                var text = document.getElementById("editor");
                var oRange = document.createRange();
                button.addEventListener("click", toggleBold, false);
                text.addEventListener('mouseup',function(e){

                    if (window.getSelection) {
                        var selection = window.getSelection();
                    } else if (document.selection) {
                        var selection = document.selection.createRange();
                    }
                    range = selection.getRangeAt(0);
                    cursorY0 = window.event.pageY;
                    console.log(cursorY0);
                })
                /*text.addEventListener("click", function () {
                    cursorY0 = window.event.pageY;
                    console.log(cursorY0);
                }, false);*/
                //console.log(window.innerHeight);
                userHeight = window.innerHeight;
            })
            );
    }
};

app.oncheckpoint = function (args) {
    // TODO: This application is about to be suspended. Save any state that needs to persist across suspensions here.
    // You might use the WinJS.Application.sessionState object, which is automatically saved and restored across suspension.
    // If you need to complete an asynchronous operation before your application is suspended, call args.setPromise().
};

function toggleBold() {
    var text = document.getElementById("editor");
    //Array.prototype.slice.apply(document.querySelectorAll("b")).forEach(function (b) {
    //    b.parentNode.replaceChild(b.firstChild, b);
    //});

    text.focus();
    var currentHeight = window.innerHeight;
    var cursorY1 = window.event.pageY;
    if (cursorY1 > currentHeight) {
        window.scrollTo(0, currentHeight - (cursorY1 - cursorY0));
    }

    var selectionContents = range.extractContents();
    var boldDom = document.createElement("b");

    boldDom.appendChild(selectionContents);
    range.insertNode(boldDom);


}

app.start();
})();

這是一個Non-JQuery方法，我想您也可以導入JQuery包，並在此處使用該方法來計算offset 。