文本在epub阅读器ios中突出显示并添加注释功能 [英] Text Highlighting and add notes function in epub reader ios

问题描述

我正在为ios和android开发epub阅读器。我想实现文本高亮，并为我的epub阅读器添加注释功能。我想知道如何为固定布局epub使用这些功能。我可以通过 javascript：window.getSelection（）获取所选对象。我想保存并检索这些对象以备将来使用。这里我用来突出显示和保存文本的代码：

I am developing epub reader for ios and android. I want to implement text highlights and add note function to my epub reader. And I want to know how to these functionality for fixed layout epub. I can get selected object by javascript:window.getSelection(). I want to save and retrieve these objects for future use. Here the code I used for highlighting and saving text:

var selection;
var storedSelections[];

function highlightText() {
if (window.getSelection) {
    selection = window.getSelection();
}
 if (selection.rangeCount > 0) {
    var range = selection.getRangeAt(0);
    var selectedText = range.toString();
    var span = document.createElement("span");
    span.id = "span_" + range.startOffset + "_" + range.endOffset ;
     alert(span.id);
    span.onclick = function() {
    myOnclikFunction(selectedText);};
span.setAttribute("class","uiWebviewHighlight");
    span.style.backgroundColor  = "skyblue";
    range.surroundContents(span);

    selection.removeAllRanges();
    selection.addRange(range);

    for (var i = 0; i < selection.rangeCount; i++) {
        storedSelections.push (selection.getRangeAt (i));
    }
    selection.removeAllRanges();
    localStorage.setItem('storedSelections',storedSelections);
}}

我使用此代码检索突出显示的文字：

I used this code for retrieve highlighted text:

function ShowStoredSelections () {
storedSelections.length=0;
var retrieved= localStorage.getItem('storedSelections');
storedSelections.push (retrieved);
var selection = window.getSelection ();
for (var i = 0; i < storedSelections.length; i++) {
    selection.removeAllRanges ();
    selection.addRange (storedSelections[i]);
    if (selection.rangeCount > 0) {
        var range = selection.getRangeAt(0);
        var selectedText = range.toString();

        var span = document.createElement("span");
        span.id = "span_" + range.startOffset + "_" + range.endOffset ;
        span.onclick = function() {
            myOnclikFunction(selectedText);
        };
        span.setAttribute("class","uiWebviewHighlight");
        span.style.backgroundColor  = "red";
        range.surroundContents(span);
        selection.removeAllRanges();
        selection.addRange(range);
    }
}}

我无法将检索到的文本添加到 selection.addRange 。我在这方面做错了什么？

I can't add retrieved text to selection.addRange. What am I doing wrong in this?

请给我一些想法或建议来解决这个问题。

Please give me some ideas or suggestions to overcome this problem.

提前感谢您的回复或回复。

Thanks in advance for any reply or answer.

推荐答案

我已经为androd的本地epub播放器实现了所有这些iOS-它是组织的产品R& D

I have implemented all these for native epub player of androd and iOS- its a product R&D for an organisation

而不是使用getSelection，请按照以下步骤操作。它很乏味但功能完全不足你的控件

Instead of using getSelection follow the below steps.Its tedious but functionality would be fully under your control

- >在webview didload的回调中给url到UIWebView（iOS）或WebView（android）


- >将所有文本单词包装成具有唯一ID的跨度


- >将触摸事件传播到webview- javascript将使用函数onTouchMove（e）处理这些触摸


- >使用 document.elementFromPoint


- >突出显示那些跨度（单词） ）
- >您将获得每个范围的位置 $（'＃wordID - '+ sWordID）.pos ition（），您可以将这些值从javascript传递到本机代码


- >将便签视图添加到webview的超级视图

-> Give url to UIWebView (iOS) or WebView (android)

-> in call back of webview didload - wrap all text words into spans with unique ids

-> propagate touch events to webview- javascript will handle those touches using function onTouchMove(e)

-> get touched span using document.elementFromPoint

-> highlight those spans (words) -> You will get position of each span $('#wordID-'+sWordID).position(),you can pass those values from javascript to native code

-> Add sticky notes view to the super view of webview

注意：最好在运行时将jQuery注入webview，将单词包装成跨度

Note: better inject jQuery in run time into webview for wrapping words into spans

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