android - android程序的意外行为

Question

我想在谷歌搜索按钮后面运行脚本，这意味着...将表单发布到谷歌服务器并以 html 字符串的形式获取响应，最后我将该字符串放在 webview 上以显示结果... .然后我运行代码...有时它会显示正确的结果(比如有人点击谷歌搜索按钮)但有时它会向我显示“强制关闭”的消息，而我对代码没有任何更改......这意味着关于输出的预测是意外的......我的代码是这样的……

public class url extends Activity
 {
    HttpResponse end = null;
    String endResult = null;
    WebView mWebView;
    Intent myWebViewIntent;
     public static  final int TIMEOUT_MS=10000;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        HttpClient client = new DefaultHttpClient();

        HttpConnectionParams.setConnectionTimeout(client.getParams(), TIMEOUT_MS);
        HttpConnectionParams.setSoTimeout(client.getParams(), TIMEOUT_MS);
        HttpPost post = new HttpPost("http://www.google.com/m");
        List<NameValuePair> pairs = new ArrayList<NameValuePair>();
        pairs.add(new BasicNameValuePair("hl", "en"));
        pairs.add(new BasicNameValuePair("gl", "us"));
        pairs.add(new BasicNameValuePair("source", "android-launcher-widget"));
        pairs.add(new BasicNameValuePair("q", "persistent"));

        try {
            post.setEntity(new UrlEncodedFormEntity(pairs));
        /*  Uri uri = Uri.parse(post.toString());
            TextView t1=new TextView(this);
            t1.setText(post.getRequestLine().getUri());
            this.setContentView(t1);*/

        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        try {
            Toast msg = Toast.makeText(url.this, "Message", Toast.LENGTH_LONG);

            msg.setGravity(Gravity.CENTER, msg.getXOffset() / 2, msg.getYOffset() / 2);

            msg.show();

            HttpResponse response = client.execute(post);

            end = response;


        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            //Toast.makeText(url.this, "problem in execute....", 20).show();
            // TODO Auto-generated catch block
            //put the balance is empty dialog box here.
            e.printStackTrace();
        }
        BasicResponseHandler myHandler = new BasicResponseHandler();
        try {

        //  Log.i("file tag","we are out of url");
            endResult = myHandler.handleResponse(end);

        } catch (HttpResponseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();

        }

    WebView engine = (WebView)findViewById(R.id.webview);
    engine.loadDataWithBaseURL(post.getRequestLine().getUri(), endResult, "text/html", "UTF-8", null);
        //engine.loadData(endResult, "text/html", "UTF-8");
        engine.requestFocus(View.FOCUS_DOWN);


         //engine.loadUrl(endResult);

    }
}

所以模拟器或安装 SDK 或程序本身有什么问题....？因为它似乎与互联网的连接已经完成，但我使用了适当的许可..谢谢..

Answer 1

您收到的 ANR 是因为您在 UI 线程上进行阻塞调用。要在不阻塞 UI 线程的情况下执行阻塞操作，您必须使用线程和处理程序，或者(推荐)AsyncTask。

参见 Painless Threading .