How to capture text in first line of current screen in Android?

Question

My projec is a e-book reader application. There is only a VebView in screen and getting data from html file. It has only text content. I need to do get text in first line of current screen. In next step, I need to find the text in document and getting the text's position of screen. Finally, I need to scroll the found position. All of things necessary to solve that problem: (WebView Text Zoom Issue in Android)

html content:

<!DOCTYPE html>

    <head>
        <style type="text/css"> 
            p{} p.x1{} p.x2{} p.x3{} p.x4{} 
            h2.x1{} h2.x2{} h2.x3{} h2.x4{}
        </style>
    </head>

    <body>

        //paragraph-1
        <p class="x1">Title-1</p>
        <p class="x2">Title-2</p>
        <p class="x3">Title-3</p>
        <p class="x4">Title-4</p>
        <p>Text content.</p>


        //paragraph-2
        <h class="x1">Title-1</p>
        <h class="x2">Title-2</p>
        <p>Text content.</p>


        //paragraph-3
        <h class="x3">Title-1</p>
        <h class="x4">Title-2</p>
        <p class="x3">Title-3</p>
        <p>Text content.</p>


        //paragraph-4
        <h class="x2">Title-1</p>
        <p class="x3">Title-2</p>
        <p>Text content.</p>


        //...

    </body>

</html>

if you dont need to render it, then why use a WebView? Just make a raw HTTP(S) request. — Matt Clark, Apr 03 '16 at 04:55

score 2 · Accepted Answer · answered Apr 03 '16 at 13:58

I think you are searching for this?

function findTopObject (elements) {
    var top = Number.POSITIVE_INFINITY;
    var obj = null;

    Array.from(elements).forEach(function (o) {
        var t = o.getBoundingClientRect(o).top;
        if (t > 0.0 && top > t) {
            obj = o;
            top = t;
        }
    });

    return obj;
}

for (var i = 0; i < 1000; i++) {
  var p = document.createElement("p");
  p.innerText = "Line " + i;
  document.body.appendChild(p);
}

var elements = document.querySelectorAll("p");
var obj = null;

window.onscroll = function() {
  if (obj != null) {
    obj.style.backgroundColor = "";
  }

  obj = findTopObject(elements);

  if (obj != null) {
    obj.style.backgroundColor = "red";
  }
};

function findTopObject(elements) {
  var top = Number.POSITIVE_INFINITY;
  var obj = null;
  Array.from(elements).forEach(function(o) {
    var t = o.getBoundingClientRect(o).top;
    if (t > 0.0 && top > t) {
      obj = o;
      top = t;
    }
  });
  return obj;
}

<body></body>

score 1 · Answer 2 · edited May 23 '17 at 12:07

There is no direct way to do what you want, First get html content by doing

HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet(url);
HttpResponse response = client.execute(request);

String html = "";
InputStream in = response.getEntity().getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
StringBuilder str = new StringBuilder();
String line = null;
while((line = reader.readLine()) != null)
{
    str.append(line);
}
in.close();
html = str.toString();

Then use sub string conccept to get what you want, have look Get Html content

Or you can use Jsoap parser to get value from specified tag in HTML

Document doc=Jsoup.connect("http://www.yahoo.com").get();
Elements elements=doc.select("img");

for(Element e:elements)
 {
  System.out.println(e.attr("src"));
 }

html file has many
...
tags mixed. I don't want to all, I want to only get first row in current screen — ATES, Apr 03 '16 at 05:10
can you show us your html source ? we can figure out what you want ? — Kathi, Apr 03 '16 at 05:14

How to capture text in first line of current screen in Android?

2 Answers2