android - fragment - 无法在 Activity 中找到按钮处理程序

Question

我是安卓新手。我的登录应用程序运行良好，但是当我将登录用户 Activity 转换为 fragment 并出现以下错误时:

错误:

12-31 05:11:36.314 26809-26809/com.androidatc.customviewindrawer E/AndroidRuntime: java.lang.IllegalStateException: Could not find a method loginUser(View) in the activity class com.androidatc.customviewindrawer.MainActivity for onClick handler on view class android.widget.Button with id 'btnLogin'
12-31 05:11:36.314 26809-26809/com.androidatc.customviewindrawer E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4052)
12-31 05:11:36.314 26809-26809/com.androidatc.customviewindrawer E/AndroidRuntime:     at android.view.View.performClick(View.java:4820)
12-31 05:11:36.314 26809-26809/com.androidatc.customviewindrawer E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:20158)

主要 Activity

package com.androidatc.customviewindrawer;

import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.app.Fragment;
//import android.support.v4.app.Fragment;
//import android.support.v4.app.FragmentManager;
import android.app.FragmentManager;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.DrawerLayout;
import android.widget.Toast;


public class MainActivity extends ActionBarActivity
        implements NavigationDrawerFragment.NavigationDrawerCallbacks,
        SearchCatFragment.OnFragmentInteractionListener,
        AndroidBarcodeQrExample.OnFragmentInteractionListener,
        BarCodeFrag.OnFragmentInteractionListener,
        LoginFrag.OnFragmentInteractionListener,
        MainViewFragment.OnFragmentInteractionListener {

    /**
     * Fragment managing the behaviors, interactions and presentation of the navigation drawer.
     */
    private NavigationDrawerFragment mNavigationDrawerFragment;

    /**
     * Used to store the last screen title. For use in {@link #restoreActionBar()}.
     */
    private CharSequence mTitle;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mNavigationDrawerFragment = (NavigationDrawerFragment)
                getFragmentManager().findFragmentById(R.id.navigation_drawer);
        mTitle = getTitle();

        // Set up the drawer.
        mNavigationDrawerFragment.setUp(
                R.id.navigation_drawer,
                (DrawerLayout) findViewById(R.id.drawer_layout));
    }

    @Override
    public void onNavigationDrawerItemSelected(int position) {
        // update the main content by replacing fragments
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.container, PlaceholderFragment.newInstance(position + 1))
                .commit();
    }



    public void onActivityResult(int requestCode, int resultCode, Intent intent) {
        if (requestCode == 0) {
            if (resultCode == RESULT_OK) {
                String contents = intent.getStringExtra("SCAN_RESULT");
                String format = intent.getStringExtra("SCAN_RESULT_FORMAT");
                Toast toast = Toast.makeText(this, "Content:" + contents + " Format:" + format, Toast.LENGTH_LONG);
                toast.show();
            }
        }
    }

    public void onSectionAttached(int number) {
        switch (number) {
            case 1:
                mTitle = getString(R.string.title_section1);
                break;
            case 2:
                mTitle = getString(R.string.title_section2);
                break;
            case 3:
                mTitle = getString(R.string.title_section3);
                break;
            case 4:
                mTitle = getString(R.string.title_section4);
                break;
            case 5:
                mTitle = getString(R.string.title_section5);
                break;
        }
    }

    public void restoreActionBar() {
        ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
        actionBar.setDisplayShowTitleEnabled(true);
        actionBar.setTitle(mTitle);
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        if (!mNavigationDrawerFragment.isDrawerOpen()) {
            // Only show items in the action bar relevant to this screen
            // if the drawer is not showing. Otherwise, let the drawer
            // decide what to show in the action bar.
            getMenuInflater().inflate(R.menu.menu_main, menu);
            restoreActionBar();
            return true;
        }
        return super.onCreateOptionsMenu(menu);
    }

    @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);
    }



    @Override
    public void onFragmentInteraction(Uri uri) {

    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";

        /**
         * Returns a new instance of this fragment for the given section
         * number.
         */
        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            return rootView;
        }

        @Override
        public void onAttach(Activity activity) {
            super.onAttach(activity);
            ((MainActivity) activity).onSectionAttached(
                    getArguments().getInt(ARG_SECTION_NUMBER));
        }
    }

}

LoginFrag.java

package com.androidatc.customviewindrawer;

import android.app.Activity;
import android.app.Fragment;
import android.app.ProgressDialog;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.loopj.android.http.AsyncHttpClient;
import com.loopj.android.http.AsyncHttpResponseHandler;
import com.loopj.android.http.RequestParams;

import cz.msebera.android.httpclient.Header;

/**
 * 
 * Login Activity Class 
 *
 */
public class LoginFrag extends Fragment {
    // Progress Dialog Object
    ProgressDialog prgDialog;
    // Error Msg TextView Object
    TextView errorMsg;
    // Email Edit View Object
    EditText emailET;
    // Passwprd Edit View Object
    EditText pwdET;
    @Override

    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View rootView = inflater.inflate(R.layout.login, container, false);

        errorMsg = (TextView) rootView.findViewById(R.id.login_error);
        // Find Email Edit View control by ID
        emailET = (EditText) rootView.findViewById(R.id.loginEmail);
        // Find Password Edit View control by ID
        pwdET = (EditText) rootView.findViewById(R.id.loginPassword);
        // Instantiate Progress Dialog object
        prgDialog = new ProgressDialog(this.getActivity());
        // Set Progress Dialog Text
        prgDialog.setMessage("Please wait...");
        // Set Cancelable as False
        prgDialog.setCancelable(false);

        return rootView;
    }
    /**
     * Method gets triggered when Login button is clicked
     * 
     * @param view
     */
    public void loginUser(View view){
        // Get Email Edit View Value
        String email = emailET.getText().toString();
        // Get Password Edit View Value
        String password = pwdET.getText().toString();
        // Instantiate Http Request Param Object
        RequestParams params = new RequestParams();

                // Put Http parameter username with value of Email Edit View control
                params.put("username", email);
                // Put Http parameter password with value of Password Edit Value control
                params.put("password", password);

        final int DEFAULT_TIMEOUT = 200000 * 1000000000;

        // Make RESTful webservice call using AsyncHttpClient object
        AsyncHttpClient client = new AsyncHttpClient();
        client.setTimeout(DEFAULT_TIMEOUT);

        client.get("http://abc/ilsdi.pl?service=AuthenticatePatron", params ,new AsyncHttpResponseHandler() {


            public void onSuccess(int i, Header[] headers, byte[] bytes) {

                Toast.makeText(getActivity().getApplicationContext(), "XML File: " + headers, Toast.LENGTH_LONG).show();


            }

            @Override
            public void onFailure(int i, Header[] headers, byte[] bytes, Throwable throwable) {
                Toast.makeText(getActivity().getApplicationContext(), "Status code :" + i + "errmsg : " + throwable.getMessage(), Toast.LENGTH_LONG).show();
                Toast.makeText(getActivity().getApplicationContext(), "Unexpected Error occcured! [Most common Error: Device might not be connected to Internet or remote server is not up and running]", Toast.LENGTH_LONG).show();

            }


            public void onSuccess(String response) {
                // Hide Progress Dialog
                prgDialog.hide();
                Toast.makeText(getActivity().getApplicationContext(), "XML File: " + response, Toast.LENGTH_LONG).show();

                    Toast.makeText(getActivity().getApplicationContext(), "You are successfully logged in!", Toast.LENGTH_LONG).show();
                    navigatetoHomeActivity();
                    //e.printStackTrace();

            }
            // When the response returned by REST has Http response code other than '200'

            public void onFailure(int statusCode, Throwable error,
                                  String content) {
                // Hide Progress Dialog
                prgDialog.hide();
                // When Http response code is '404'
                if(statusCode == 404){
                    Toast.makeText(getActivity().getApplicationContext(), "Requested resource not found", Toast.LENGTH_LONG).show();
                }
                // When Http response code is '500'
                else if(statusCode == 500){
                    Toast.makeText(getActivity().getApplicationContext(), "Something went wrong at server end", Toast.LENGTH_LONG).show();
                }
                // When Http response code other than 404, 500
                else{
                    Toast.makeText(getActivity().getApplicationContext(), "Status code :" + statusCode + "errmsg : " + error.getMessage(), Toast.LENGTH_LONG).show();
                    Toast.makeText(getActivity().getApplicationContext(), "Unexpected Error occcured! [Most common Error: Device might not be connected to Internet or remote server is not up and running]", Toast.LENGTH_LONG).show();
                }
            }
        });



    }

    /**
     * Method which navigates from Login Activity to Home Activity
     */
    public void navigatetoHomeActivity(){
        Intent homeIntent = new Intent(getActivity().getApplicationContext(),HomeActivity.class);
        homeIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        startActivity(homeIntent);
    }

    public interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        public void onFragmentInteraction(Uri uri);
    }





}

登录.xml

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:padding="10dip" >

        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="10dip"
            android:text="@string/login_title"
            android:textSize="25sp"
            android:textStyle="bold" />

        <EditText
            android:id="@+id/loginEmail"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:hint="Enter your User ID"
            android:inputType="textEmailAddress" />

        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="15dip"
            android:text="@string/pwd" />

        <EditText
            android:id="@+id/loginPassword"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:hint="Enter Password"
            android:inputType="textPassword" />

        <TextView
            android:id="@+id/login_error"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:padding="10dip"
            android:textColor="#e30000"
            android:textStyle="bold" />

        <Button
            android:id="@+id/btnLogin"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="20dip"
            android:background="#ff6347"
            android:onClick="loginUser"
            android:text="Login"
            android:textColor="#fff" />

        <Button
            android:id="@+id/btnLinkToRegisterScreen"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="40dip"
            android:background="@null"
            android:onClick="navigatetoRegisterActivity"
            android:text="Signup"
            android:textColor="#228b22"
            android:textStyle="bold" />
    </LinearLayout>

</ScrollView>

感谢任何建议。谢谢

Answer 1

使用 setOnClickListener 。从 XML 中删除 android:onClick="loginUser"(仅用于 fragment )

  <Button
                android:id="@+id/btnLogin"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:layout_marginTop="20dip"
                android:background="#ff6347"
                android:text="Login"
                android:textColor="#fff" />

然后将其添加到您的 onCreateView 部分

    Button button = (Button) view.findViewById(R.id.btnLogin):
   button.setOnClickListener(new OnClickListener()
   {
             @Override
             public void onClick(View v)
             {
                // Add your code
             } 
   });