Warning: file_get_contents(/data/phpspider/zhask/data//catemap/9/java/327.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
如何解决此问题:执行doInBackground()时发生致命异常Asynctask#1 java.lang.RuntimeException错误_Java_Android_Android Asynctask - Fatal编程技术网

如何解决此问题:执行doInBackground()时发生致命异常Asynctask#1 java.lang.RuntimeException错误

如何解决此问题:执行doInBackground()时发生致命异常Asynctask#1 java.lang.RuntimeException错误,java,android,android-asynctask,Java,Android,Android Asynctask,我是从android连接到php的新手。 这是我的代码: package com.example.androidhive; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.Button; public class tesMainScreen extends Activity

我是从android连接到php的新手。 这是我的代码:

package com.example.androidhive;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;


public class tesMainScreen extends Activity{

    Button btnViewProducts;
    Button btnNewProduct;

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

        // Buttons
        btnViewProducts = (Button) findViewById(R.id.btnViewProducts);
        btnNewProduct = (Button) findViewById(R.id.btnCreateProduct);

        // view products click event
        btnViewProducts.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View view) {
                // Launching All products Activity
                Intent i = new Intent(getApplicationContext(), AllProductsActivity.class);
                startActivity(i);

            }
        });

        // view products click event
        btnNewProduct.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View view) {
                // Launching create new product activity
                Intent i = new Intent(getApplicationContext(), NewProductActivity.class);
                startActivity(i);

            }
        });
    }
}
这就是doinBackground存在的地方:

package com.example.androidhive;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

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://10.0.2.2/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("{http://10.0.2.2/android_connect/create_product.php}",
                    "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;
        }
        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once done

            pDialog.dismiss();
        }

    }
}

因此,请帮助我,谢谢。

将下面的内容调用到onPostExecute中:-

                Intent i = new Intent(getApplicationContext(), AllProductsActivity.class);
                startActivity(i);

                // closing this screen
                finish();
选中onPostExecute上的Disclose

        if(dialog != null && dialog.isShowing())
            dialog.dismiss();
UI元素只能从UI线程更新。使用异步任务执行后台word,并修改在UI线程上运行的onPostExecute中的UI。此错误:

活动[…]泄漏了window com.android.internal.policy.impl.PhoneWindow$DecorView@4052ea40原来是加在这里的

发生的原因是您试图在
对话框
仍在显示时启动另一个
活动
。您试图从
onPostExecute
中取消它,这是正确的方法,但是,您调用一个新的
Intent
并从
doInBackground
启动一个新活动。然后,系统无法访问
onPostExecute
,因为您没有从
doInBackground

按如下方式更改您的方法:

protected String doInBackground(String... args) {
    String isLoaded;
    // ...
    try {
        int success = json.getInt(TAG_SUCCESS);
        if (success == 1) {
            // success: return a string value "success"
            isLoaded = "Success";
        } else {
            // failed: return a string value "failed"
            isLoaded = "Failed";
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
    // return this String value to onPostExecute
    return isLoaded;
}

// then retrieve this value by param "file_url"
protected void onPostExecute(String file_url) {
    // dismiss the dialog once done
    pDialog.dismiss();
    if(file_url.equals("Success") {
        // success: launch another activity
        Intent i = new Intent(NewProductActivity.this, AllProductsActivity.class);
        startActivity(i);
        NewProductActivity.this.finish();
    } else if(file_url.equals("Failed") {
        // failed: do something
        Toast.makeText(NewProductActivity.this, "An error occurred...", Toast.LENGTH_SHORT).show();
    }
}  
另外,如果用户退出应用程序,您可以从
onPause
(或
onDestroy
)方法调用
discouse
。如果他回来了,你只需要稍后再取回它:

@Override
public void onPause(){
    super.onPause();
    if(pDialog != null)
        pDialog.dismiss();
}

如果(success==1){pDialog.disease();}并删除
pDialog.disease(),则尝试执行此
onPostExecute(…)
不调用
startActivity(i)
finish()
函数中的
doInBackground(String…args)
。从
doInBackground(string…args)”以字符串形式返回信息,然后根据信息的值在
onPostExecute(string info)`中执行操作。已尝试,仍然错误,是否再次使用任何方法?有人能帮我吗?相同,05-09 11:26:43.417:error/AndroidRuntime(637):致命异常:AsyncTask#1 05-09 11:26:43.417:错误/AndroidRuntime(637):java.lang.RuntimeException:执行doInBackground()时发生的错误仍然显示相同的错误,这让我很困惑。因此,我的onPostExecute现在是:Intent i=newintent(getApplicationContext(),AllProductsActivity.class);星触觉(i);//关闭此屏幕完成();如果(pDialog!=null&&pDialog.isShowing())pDialog.disclose();我认为您需要更改
getApplicationContext
,我猜它是附加到上下文
temain屏幕
的,而不是
NewProductActivity
类。对
tesmain屏幕中的
Intents
执行相同操作。请参阅我的编辑。还有@stevian12,对于
InputDispatcher
错误,我真的不知道如何解决这个问题,但也可能会有所帮助。非常感谢您的帮助,但仍然是一样的,这很奇怪。
@Override
public void onPause(){
    super.onPause();
    if(pDialog != null)
        pDialog.dismiss();
}