为什么当我点击安卓应用程序上的搜索按钮时它会弹出主页

Question

我是创建安卓应用程序的初学者。我将创建一个求职应用程序，我在编辑文本字段中输入关键字，如果我按下搜索按钮，将显示相关的工作信息：

---

输入职位：

[_____edittext_1_____]

输入位置：

[_____edittext_2_____]

"搜索"按钮

*问题是，例如，如果我在编辑文本 1 中输入"程序员"，在编辑文本 2 中输入"纽约"，然后按下搜索按钮，则不会显示相关结果。相反，它只是弹出 这个主页/界面页面 . 我按下搜索按钮，它不断返回同一页面！

主要活动.java

public class MainActivity extends ActionBarActivity implements OnClickListener  {
Button button; 
private EditText keywordSearch;                                          
private EditText locationSearch;                                                      
private Button jobSearchButton;                                           
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    addListenerOnButton(); 
    //link to UI
    keywordSearch=(EditText)findViewById(R.id.keywordSearch);                    
    locationSearch=(EditText)findViewById(R.id.locationSearch);           
    jobSearchButton=(Button)findViewById(R.id.jobSearchButton);                 
    jobSearchButton.setOnClickListener(this);                                   

}

public void onClick(View v) {                                                    
    if(v.getId()==R.id.jobSearchButton){                                         
        Intent searchIntent = new Intent(this, MainActivity.class);                      
        //send the keyword to the next screen
        searchIntent.putExtra("key",keywordSearch.getText().toString());         
        searchIntent.putExtra("key",locationSearch.getText().toString());     
    //call the screen for listing
        startActivity(searchIntent);                                             
    }                                                                            
}                                                                                

    public void addListenerOnButton() {
        final Context context = this;
        button = (Button) findViewById(R.id.button2);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                Intent intent = new Intent(context, FavouriteActivity.class);
                startActivity(intent);
            }
        });
    }

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

列表结果.java

public class ListResult extends ListActivity {
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> idiomsList;
// url to get the idiom list
private static String url_search = "http://localhost/get_json.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_POSTNAMEIOMS = "idioms";
private static final String TAG_POSTNAME = "PostName";
private static final String TAG_LOCATION = "Location";
private static final String TAG_SALARY = "Salary";
// products JSONArray
JSONArray idioms = null;
//search key value
public String searchkey;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_list_result);
    Intent myIntent = getIntent();
// gets the arguments from previously created intent
    searchkey = myIntent.getStringExtra("PostName");
    searchkey = myIntent.getStringExtra("Location");
// Hashmap for ListView
    idiomsList = new ArrayList<HashMap<String, String>>();
// Loading idioms in Background Thread
    new LoadIdioms().execute();
// Get listview
    ListView lv = getListView();
// on seleting single idioms
// to do something
    lv.setOnItemClickListener(new OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {
// getting values from selected ListItem
            String iid = ((TextView) view.findViewById(R.id.id)).getText()
                    .toString();
        }
    });
}
/**
 * Background Async Task to Load Idioms by making HTTP Request
 * */
class LoadIdioms extends AsyncTask<String, String, String> {
    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(ListResult.this);
        pDialog.setMessage("Loading IDIOMS. Please wait...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }
    /**
     * getting Idioms from url
     * */
    protected String doInBackground(String... args) {
// Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
//value captured from previous intent
        params.add(new BasicNameValuePair("PostName", searchkey));
        params.add(new BasicNameValuePair("Location", searchkey));
// getting JSON string from URL
        JSONObject json = jParser.makeHttpRequest(url_search, "GET", params);
// Check your log cat for JSON response
        Log.d("Search idioms: ", json.toString());
        try {
// Checking for SUCCESS TAG
            int success = json.getInt(TAG_SUCCESS);
            if (success == 1) {
// products found
// Getting Array of Products
                idioms = json.getJSONArray(TAG_POSTNAMEIOMS);
// looping through All Products
                for (int i = 0; i < idioms.length(); i++) {
                    JSONObject c = idioms.getJSONObject(i);
// Storing each json item in variable
                    String id = c.getString(TAG_POSTNAME);
                    String entry = c.getString(TAG_LOCATION);
                    String meaning = c.getString(TAG_SALARY);
// creating new HashMap
                    HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
                    map.put(TAG_POSTNAME, id);
                    map.put(TAG_LOCATION, entry);
                    map.put(TAG_SALARY, meaning);
// adding HashList to ArrayList
                    idiomsList.add(map);
                }
            } else {
// no idioms found
//do something
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
//return "success";
        return null;
    }
    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String file_url) {
// dismiss the dialog after getting the related idioms
        pDialog.dismiss();
// updating UI from Background Thread
        runOnUiThread(new Runnable() {
            public void run() {
/**
* Updating parsed JSON data into ListView
* */
                ListAdapter adapter = new SimpleAdapter(
                        ListResult.this, idiomsList,
                        R.layout.list_view, new String[] { TAG_POSTNAME, TAG_LOCATION, TAG_SALARY},
                        new int[] { R.id.id, R.id.entry, R.id.meaning});
// updating listview
                setListAdapter(adapter);
            }
        });
    }
}
}

JSONParser.java

public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
                                  List<NameValuePair> params) {
// Making HTTP request
    try {
// check for request method
        if(method == "POST"){
// request method is POST
// defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));
            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();
        }else if(method == "GET"){
// request method is GET
            DefaultHttpClient httpClient = new DefaultHttpClient();
            String paramString = URLEncodedUtils.format(params, "utf-8");
            url += "?" + paramString;
            HttpGet httpGet = new HttpGet(url);
            HttpResponse httpResponse = httpClient.execute(httpGet);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();
        }
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    try {
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                is, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null) {
            sb.append(line + "n");
        }
        is.close();
        json = sb.toString();
    } catch (Exception e) {
        Log.e("Buffer Error", "Error converting result " + e.toString());
    }
// try parse the string to a JSON object
    try {
        jObj = new JSONObject(json);
    } catch (JSONException e) {
        Log.e("JSON Parser", "Error parsing data " + e.toString());
    }
// return JSON String
    return jObj;
}
}

清单.xml

  <uses-permission android:name="android.permission.INTERNET" />
<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".FavouriteActivity"
        android:label="favourite" >
    </activity>
    <activity
        android:name=".ListResult"
        android:label="@string/title_activity_list_result" >
    </activity>
</application>

Answer 1

我想

你正在回忆MainActivity内部onClick事件的MainActivity。在这里

Intent searchIntent = new Intent(this, MainActivity.class);

通过猜测您的流程，它应该替换为

Intent searchIntent = new Intent(this, ListResult.class);

Answer 2

我onClick方法中强调了您的错误。尝试，并小心。祝你好运:)

---

Intent searchIntent = new Intent（this， ListResult.class）;
searchIntent.putExtra（"PostName"，keywordSearch.getText（）.toString（））;
searchIntent.putExtra（"Location"，locationSearch.getText（）.toString（））;