Android HTTP 获取

我查看了一些论坛帖子，但找不到我的问题的答案。我正在尝试从 php 文件获取响应。 php 文件正在运行。问题是 Android 应用程序不会执行我的请求。以下是我的代码的两个示例以及我在文本视图中得到的结果：

public void changText(View view) {
    TextView textv = (TextView)findViewById(R.id.textview1);
    textv.setText("Text Has Been Changed");
    BufferedReader in = null;
    String data = null;

    try{
           HttpClient httpclient = new DefaultHttpClient();

           HttpGet request = new HttpGet();
           URI website = new URI("http://alanhardin.comyr.com/matt24/matt28.php");
           request.setURI(website);
           HttpResponse response = httpclient.execute(request);
           in = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));

           textv.append(" Connected ");
       }catch(Exception e){
           Log.e("log_tag", "Error in http connection "+e.toString());
       }


   }

TextView 显示：文本已更改

    public void changText(View view) {
    TextView textv = (TextView)findViewById(R.id.textview1);
    textv.setText("Text Has Been Changed");
    BufferedReader in = null;
    String data = null;

    try{
           HttpClient httpclient = new DefaultHttpClient();

           HttpGet request = new HttpGet();
           URI website = new URI("http://alanhardin.comyr.com/matt24/matt28.php");
           request.setURI(website);
           //HttpResponse response = httpclient.execute(request);
           //in = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));

           textv.append(" Connected ");
       }catch(Exception e){
           Log.e("log_tag", "Error in http connection "+e.toString());
       }


   }

TextView 显示：文本已更改已连接

在这个清单中我有：

<uses-permission android:name="android.permission.INTERNET" />

在错误日志中我得到以下内容： http连接时出错 android.os.NetworkOnMainThreadException

任何帮助，将不胜感激。

Android 可能会很好地执行您的请求。您似乎只是忽略了服务器返回的数据。你可以这样做，例如：

public void changText(View view) {
    TextView textv = (TextView)findViewById(R.id.textview1);
    textv.setText("Text Has Been Changed");
    BufferedReader in = null;
    String data = null;

    try{
           HttpClient httpclient = new DefaultHttpClient();

           HttpGet request = new HttpGet();
           URI website = new URI("http://alanhardin.comyr.com/matt24/matt28.php");
           request.setURI(website);
           HttpResponse response = httpclient.execute(request);
           in = new BufferedReader(new InputStreamReader(
                   response.getEntity().getContent()));

           // NEW CODE
           String line = in.readLine();
           textv.append(" First line: " + line);
           // END OF NEW CODE

           textv.append(" Connected ");
       }catch(Exception e){
           Log.e("log_tag", "Error in http connection "+e.toString());
       }
}

看起来您的服务器正在返回一个 JSON 对象，因此您可能想要做一些更智能的事情，例如读取整个响应，解析它（使用new JSONArray(response)），并提取相关字段，但上面的代码至少会验证 Android 是否正在执行您的查询。

编辑：从您报告的异常来看，您似乎正在主 UI 线程上运行代码。从 API 11 开始，这是被禁止的（并且在此之前曾被人皱眉）。有几篇文章介绍了如何解决此问题。请参阅指南主题无痛穿线 http://android-developers.blogspot.com/2009/05/painless-threading.html以及教程here http://blog.vogella.com/2012/02/22/android-strictmode-networkonmainthreadexception/ and here http://www.techblogistech.com/2011/11/how-to-fix-the-android-networkonmainthreadexception/。另请参阅这个线程 https://stackoverflow.com/questions/6343166/android-os-networkonmainthreadexception了解更多信息。