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activity-Postparameter报错误信息

程序员文章站 2022-05-23 18:59:54
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activitymysqlandroidandroid intent

我建了一个app,在应用程序中,当点击按钮时就发送一个字符串给下一个activity,在第二个activity中我用这个值从数据库中检索数据。
下边是代码

Intent myIntent = getIntent(); // 从前一个activity中获得值myIntent.getStringExtra("lbl_name");postParameters = new ArrayList();postParameters.add(new BasicNameValuePair("product", lbl_name//传递name给database .getText().toString()));

问题是它不会继承lbl_name

我在网上找了很久,但是都没有找到解决方法。麻烦告诉我一下这么做对不对?

传递值的代码.

Intent myIntent = new Intent(SinglePlaceActivity.this,RecoProd.class);                                        myIntent.putExtra("lbl_name", "lbl_name");                                        SinglePlaceActivity.this.startActivity(myIntent);

访问数据库的代码.

public class RecoProd extends Activity {    EditText pd;    TextView error;    ArrayList postParameters;    /** 当activity第一次被创建的时候调用 */    @Override    public void onCreate(Bundle savedInstanceState) {        try {            Class> strictModeClass = Class.forName("android.os.StrictMode", true, Thread.currentThread()                    .getContextClassLoader());            Class> threadPolicyClass = Class.forName("android.os.StrictMode$ThreadPolicy", true, Thread                    .currentThread().getContextClassLoader());            Class> threadPolicyBuilderClass = Class.forName("android.os.StrictMode$ThreadPolicy$Builder", true,                    Thread.currentThread().getContextClassLoader());            Method setThreadPolicyMethod = strictModeClass.getMethod("setThreadPolicy", threadPolicyClass);            Method detectAllMethod = threadPolicyBuilderClass.getMethod("detectAll");            Method penaltyMethod = threadPolicyBuilderClass.getMethod("penaltyLog");            Method buildMethod = threadPolicyBuilderClass.getMethod("build");            Constructor> threadPolicyBuilderConstructor = threadPolicyBuilderClass.getConstructor();            Object threadPolicyBuilderObject = threadPolicyBuilderConstructor.newInstance();            Object obj = detectAllMethod.invoke(threadPolicyBuilderObject);            obj = penaltyMethod.invoke(obj);            Object threadPolicyObject = buildMethod.invoke(obj);            setThreadPolicyMethod.invoke(strictModeClass, threadPolicyObject);        } catch (Exception ex) {            String TAG = null;            Log.w(TAG, ex);        }        super.onCreate(savedInstanceState);        setContentView(R.layout.recomain);        Intent myIntent = getIntent(); // 从前一个activity中获得值        String lbl_name= myIntent.getStringExtra("lbl_name");//();                postParameters.add(new BasicNameValuePair("product", lbl_name                        ));                // String valid = "1";                DownloadWebPageTask dw = new DownloadWebPageTask();                dw.execute("");    }    private class DownloadWebPageTask extends AsyncTask {        @Override        protected String doInBackground(String... urls) {            String response = null;            for (String url : urls) {                try {                    response = CustomHttpClient.executeHttpPost("http://192.168.1.7/abc/check2.php", postParameters);                      String res = response.toString();                    // res = res.trim();                    res = res.replaceAll("\\s+", "");                    // error.setText(res);                    try{                        res = "";                  JSONArray jArray = new JSONArray(res);                        for(int i=0;i "+ json_data.getString("prod_name");                        }                }                catch(JSONException e){                        Log.e("log_tag", "Error parsing data "+e.toString());                }                try{                 error.setText(res);                }                catch(Exception e){                 Log.e("log_tag","Error in Display!" + e.toString());;                          }              }                 catch (Exception e) {            Log.e("log_tag","Error in http connection!!" + e.toString());                }            }            return response;               }        @Override        protected void onPostExecute(String result) {        }    }}