Phonegap File API

經過數週的研究，我決定使用Phonegap的File API來更新我的應用程序。在PhoneGap的谷歌I組發現，我必須要經過以下步驟：Phonegap File API

負載使用XHR
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我已經沒有第1步，我的文件，目前正在XHR加載。現在我陷入了第2步。我嘗試了filewriter，但沒有成功，Phonegap的File API上的信息並不十分清晰。誰能幫我這個？

這裏是我的XHR腳本：

<script language="javascript" type="text/javascript"> 
function loadHome() { 
    var request = new XMLHttpRequest(); 
    request.open("GET", "file:///sdcard/Download/home.json", true); 
    request.onreadystatechange = function() {//Call a function when the state changes. 
    if (request.readyState == 4) { 
     if (request.status == 200 || request.status == 0) { 

      var home = JSON.parse(request.responseText); 
      var data = "<table cellspacing='0'>"; 
      for (i = 0; i < home.length; i++) { 
       data += "<td>"; 
       data += "<a href='" + home[i].link + "'/>"; 
       data += "<img src='" + home[i].img + "'/>"; 
       data += "<div class='dsc'>" + home[i].expo + "<br><em>"; 
       data += home [i].datum + "</em></div></a></td>"; 
      } 
      data += "</table>"; 
      var twitter = document.getElementById("home2"); 
      twitter.innerHTML = data; 
     } 
    } 
} 
console.log("asking for home"); 
request.send(); 

</script>

這是我的第一次嘗試在FileWriter的：

<script type="text/javascript" charset="utf-8"> 

document.addEventListener("deviceready", onDeviceReady, false); 

function onDeviceReady() { 
    window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, gotFS, fail); 
} 

function gotFS(fileSystem) { 
    fileSystem.root.getFile("file:///sdcard/Download/home.json", {create: true, exclusive: false}, gotFileEntry, fail); 
} 

function gotFileEntry(fileEntry) { 
    fileEntry.createWriter(gotFileWriter, fail); 
} 

function gotFileWriter(writer) { 
    writer.onwriteend = function(evt) { 
     console.log("contents of file now 'some sample text'"); 
     writer.truncate(11); 
     writer.onwriteend = function(evt) { 
      console.log("contents of file now 'some sample'"); 
      writer.seek(4); 
      writer.write(" different text"); 
      writer.onwriteend = function(evt){ 
       console.log("contents of file now 'some different text'"); 
      } 
     }; 
    }; 
    writer.write("some sample text"); 
} 

function fail(error) { 
    console.log(error.code); 
} 

</script>

來源

2013-07-21 user2471501