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我正在使用以下代码将项目添加到 mysql 数据库。单击按钮时，它应该开始将数据上传到服务器的异步任务。但是当我运行它时，我收到错误消息“此应用程序可能是LogCat 在其主线程中做了太多工作。我该如何解决这个代码问题，谢谢。

public class NewProductActivity extends Activity {

// Progress Dialog
private ProgressDialog pDialog;

JSONParser jsonParser = new JSONParser();
EditText inputName;
EditText inputPrice;
EditText inputDesc;

// url to create new product
private static String url_create_product = "http://localhost/android_connect/create_product.php";

// JSON Node names
private static final String TAG_SUCCESS = "success";

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.add_product);

    // Edit Text
    inputName = (EditText) findViewById(R.id.inputName);
    inputPrice = (EditText) findViewById(R.id.inputPrice);
    inputDesc = (EditText) findViewById(R.id.inputDesc);

    // Create button
    Button btnCreateProduct = (Button) findViewById(R.id.btnCreateProduct);

    // button click event
    btnCreateProduct.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View view) {
            // creating new product in background thread

            new CreateNewProduct().execute();

        }
    });
}

/**
 * Background Async Task to Create new product
 * */
class CreateNewProduct extends AsyncTask<String, String, String> {

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(NewProductActivity.this);
        pDialog.setMessage("Creating Product..");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    /**
     * Creating product
     * */
    protected String doInBackground(String... args) {
        String name = inputName.getText().toString();
        String price = inputPrice.getText().toString();
        String description = inputDesc.getText().toString();

        // Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("name", name));
        params.add(new BasicNameValuePair("price", price));
        params.add(new BasicNameValuePair("description", description));

        // getting JSON Object
        // Note that create product url accepts POST method
        JSONObject json = jsonParser.makeHttpRequest(url_create_product,
                "POST", params);

        // check log cat fro response
        Log.d("Create Response", json.toString());

        // check for success tag
        try {
            int success = json.getInt(TAG_SUCCESS);

            if (success == 1) {
                // successfully created product
                Intent i = new Intent(getApplicationContext(), AllProductsActivity.class);
                startActivity(i);

                // closing this screen
                finish();
            } else {
                // failed to create product
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }

        return null;
    }

这是 LogCat 输出：

05-08 12:51:26.761: I/Choreographer(762): Skipped 31 frames!  The application may be doing too much work on its main thread.
05-08 12:51:28.632: W/System.err(762): org.apache.http.conn.HttpHostConnectException: "Connection to localhost refused
05-08 12:51:28.672: W/System.err(762):  at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:183)
05-08 12:51:28.672: W/System.err(762):  at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
05-08 12:51:28.712: W/System.err(762):  at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
05-08 12:51:28.712: W/System.err(762):  at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
05-08 12:51:28.832: W/System.err(762):  at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
05-08 12:51:28.902: W/System.err(762):  at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
05-08 12:51:29.012: W/System.err(762):  at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
05-08 12:51:29.072: W/System.err(762):  at com.example.androidhive.JSONParser.makeHttpRequest(JSONParser.java:51)
05-08 12:51:29.072: W/System.err(762):  at com.example.androidhive.NewProductActivity$CreateNewProduct.doInBackground(NewProductActivity.java:97)
05-08 12:51:29.172: W/System.err(762):  at com.example.androidhive.NewProductActivity$CreateNewProduct.doInBackground(NewProductActivity.java:1)
05-08 12:51:29.252: W/System.err(762):  at android.os.AsyncTask$2.call(AsyncTask.java:287)
05-08 12:51:29.312: W/System.err(762):  at java.util.concurrent.FutureTask.run(FutureTask.java:234)
05-08 12:51:29.322: W/System.err(762):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
05-08 12:51:29.342: W/System.err(762):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
05-08 12:51:29.342: W/System.err(762):  at java.lang.Thread.run(Thread.java:856)
05-08 12:51:29.372: W/System.err(762): Caused by: java.net.ConnectException: failed to connect to /127.0.0.1 (port 80): connect failed: ECONNREFUSED (Connection refused)
05-08 12:51:29.442: W/System.err(762):  at libcore.io.IoBridge.connect(IoBridge.java:114)
05-08 12:51:29.493: W/System.err(762):  at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
05-08 12:51:29.552: W/System.err(762):  at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
05-08 12:51:29.552: W/System.err(762):  at java.net.Socket.connect(Socket.java:842)
05-08 12:51:29.572: W/System.err(762):  at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
05-08 12:51:29.652: W/System.err(762):  at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
05-08 12:51:29.692: W/System.err(762):  ... 14 more
05-08 12:51:29.763: W/System.err(762): Caused by: libcore.io.ErrnoException: connect failed: ECONNREFUSED (Connection refused)
05-08 12:51:29.872: W/System.err(762):  at libcore.io.Posix.connect(Native Method)
05-08 12:51:29.872: W/System.err(762):  at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85)
05-08 12:51:29.892: W/System.err(762):  at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
05-08 12:51:29.992: W/System.err(762):  at libcore.io.IoBridge.connect(IoBridge.java:112)
05-08 12:51:29.992: W/System.err(762):  ... 19 more
05-08 12:51:30.102: E/Buffer Error(762): Error converting result java.lang.NullPointerException: lock == null
05-08 12:51:30.212: E/JSON Parser(762): Error parsing data org.json.JSONException: End of input at character 0 of 
05-08 12:51:30.302: W/dalvikvm(762): threadid=14: thread exiting with uncaught exception (group=0x40a71930)
05-08 12:51:30.602: E/AndroidRuntime(762): FATAL EXCEPTION: AsyncTask #4
05-08 12:51:30.602: E/AndroidRuntime(762): java.lang.RuntimeException: An error occured while executing doInBackground()
05-08 12:51:30.602: E/AndroidRuntime(762):  at android.os.AsyncTask$3.done(AsyncTask.java:299)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.util.concurrent.FutureTask.run(FutureTask.java:239)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.lang.Thread.run(Thread.java:856)
05-08 12:51:30.602: E/AndroidRuntime(762): Caused by: java.lang.NullPointerException
05-08 12:51:30.602: E/AndroidRuntime(762):  at com.example.androidhive.NewProductActivity$CreateNewProduct.doInBackground(NewProductActivity.java:101)    
05-08 12:51:30.602: E/AndroidRuntime(762):  at com.example.androidhive.NewProductActivity$CreateNewProduct.doInBackground(NewProductActivity.java:1)
05-08 12:51:30.602: E/AndroidRuntime(762):  at android.os.AsyncTask$2.call(AsyncTask.java:287)
05-08 12:51:30.602: E/AndroidRuntime(762):  at java.util.concurrent.FutureTask.run(FutureTask.java:234)
05-08 12:51:30.602: E/AndroidRuntime(762):  ... 3 more
05-08 12:51:32.542: I/Choreographer(762): Skipped 395 frames!  The application may be doing too much work on its main thread.
05-08 12:51:32.752: I/Choreographer(762): Skipped 54 frames!  The application may be doing too much work on its main thread.
05-08 12:51:33.892: I/Choreographer(762): Skipped 295 frames!  The application may be doing too much work on its main thread.
05-08 12:51:34.132: I/Choreographer(762): Skipped 58 frames!  The application may be doing too much work on its main thread.
05-08 12:51:35.762: E/WindowManager(762): Activity com.example.androidhive.NewProductActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{40d3d5e0 V.E..... R.....ID 0,0-329,175} that was originally added here
05-08 12:51:35.762: E/WindowManager(762): android.view.WindowLeaked: Activity com.example.androidhive.NewProductActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{40d3d5e0 V.E..... R.....ID 0,0-329,175} that was originally added here
05-08 12:51:35.762: E/WindowManager(762):   at android.view.ViewRootImpl.<init>(ViewRootImpl.java:354)
05-08 12:51:35.762: E/WindowManager(762):   at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:216)
05-08 12:51:35.762: E/WindowManager(762):   at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
05-08 12:51:35.762: E/WindowManager(762):   at android.app.Dialog.show(Dialog.java:281)
05-08 12:51:35.762: E/WindowManager(762):   at com.example.androidhive.NewProductActivity$CreateNewProduct.onPreExecute(NewProductActivity.java:78)
05-08 12:51:35.762: E/WindowManager(762):   at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
05-08 12:51:35.762: E/WindowManager(762):   at android.os.AsyncTask.execute(AsyncTask.java:534)
05-08 12:51:35.762: E/WindowManager(762):   at com.example.androidhive.NewProductActivity$1.onClick(NewProductActivity.java:57)
05-08 12:51:35.762: E/WindowManager(762):   at android.view.View.performClick(View.java:4204)
05-08 12:51:35.762: E/WindowManager(762):   at android.view.View$PerformClick.run(View.java:17355)
05-08 12:51:35.762: E/WindowManager(762):   at android.os.Handler.handleCallback(Handler.java:725)
05-08 12:51:35.762: E/WindowManager(762):   at android.os.Handler.dispatchMessage(Handler.java:92)
05-08 12:51:35.762: E/WindowManager(762):   at android.os.Looper.loop(Looper.java:137)
05-08 12:51:35.762: E/WindowManager(762):   at android.app.ActivityThread.main(ActivityThread.java:5041)
05-08 12:51:35.762: E/WindowManager(762):   at java.lang.reflect.Method.invokeNative(Native Method)
05-08 12:51:35.762: E/WindowManager(762):   at java.lang.reflect.Method.invoke(Method.java:511)
05-08 12:51:35.762: E/WindowManager(762):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-08 12:51:35.762: E/WindowManager(762):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-08 12:51:35.762: E/WindowManager(762):   at dalvik.system.NativeStart.main(Native Method)
05-08 12:51:35.812: I/Choreographer(762): Skipped 172 frames!  The application may be doing too much work on its main thread.
05-08 12:51:36.172: I/Process(762): Sending signal. PID: 762 SIG: 9
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1 回答 1

0

虽然它似乎没有明显相关，但在您发布的 logcat 中，代码正在执行：

JSONObject json = jsonParser.makeHttpRequest(url_create_product,
            "POST", params);

当代码终止时。这个请求似乎也失败了（“无法连接到本地主机”）。可能是当这个请求失败时，其他东西会以某种方式进入 UI 线程。无论哪种方式，这个异常都应该被捕获并更干净地处理。

于 2013-05-08T13:46:37.907 回答