Question

我正在尝试将此日历应用添加到标签操作栏中。但是，当我将所有代码加入到一起尝试完成应用程序时，我会遇到很多错误。

引起：android.content.ActivityNotFoundException：无法找到显式活动类

它告诉我，我应该尝试将它添加到android清单中，但因为它们是片段肯定你不能将片段添加到android清单中，无论如何这里是我的代码......

package com.idkstudios.shiftcalculator;

import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;

import com.idkstudios.shiftcalculator.tab.TabsPagerAdapter;

public class MainActivity extends AppCompatActivity implements ActionBar.TabListener {

    private ViewPager viewPager;
    private TabsPagerAdapter adapter;
    private ActionBar actionBar;

    /**
     * Tab titles
     */
    private String[] tabTitles = {"Hours List", "Calendar", "Pay"};

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

        viewPager = (ViewPager) findViewById(R.id.pager);
        actionBar = getSupportActionBar();
        adapter = new TabsPagerAdapter(getSupportFragmentManager());

        viewPager.setAdapter(adapter);
        actionBar.setHomeButtonEnabled(false);
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        /**
         * For adding tabs
         */
        for(String tabs : tabTitles){
            actionBar.addTab(actionBar.newTab().setText(tabs).setTabListener(this));
        }

        viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageSelected(int position) {
                actionBar.setSelectedNavigationItem(position);
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab, android.support.v4.app.FragmentTransaction ft) {
        viewPager.setCurrentItem(tab.getPosition());
    }

    @Override
    public void onTabReselected(ActionBar.Tab tab, android.support.v4.app.FragmentTransaction ft) {

    }

    @Override
    public void onTabUnselected(ActionBar.Tab tab, android.support.v4.app.FragmentTransaction ft) {

    }
}

这是我的主要活动，这是三个片段，

package com.idkstudios.shiftcalculator.fragments;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.ImageButton;
import android.widget.TextView;

import com.idkstudios.shiftcalculator.R;
import com.idkstudios.shiftcalculator.calendar.adapter.CalendarAdapter;
import com.idkstudios.shiftcalculator.calendar.util.CalendarCollection;

import java.util.GregorianCalendar;

/**
 * Created by Toby on 02/09/2015.
 */
public class CalendarFragment extends Fragment {

    /**
     * The basic variables that you will need for the calendar
     */
    public GregorianCalendar cal_month, cal_month_copy;
    private CalendarAdapter cal_adapter;
    private TextView tv_month;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        /**
         * Sets up the basic layout file, we return this later
         */
        View rootView = inflater.inflate(R.layout.fragment_calendar, container, false);

        cal_month = (GregorianCalendar) GregorianCalendar.getInstance();
        cal_month_copy = (GregorianCalendar) cal_month.clone();
        cal_adapter = new CalendarAdapter(getActivity(), cal_month, CalendarCollection.date_collection_arr);

        tv_month = (TextView) getActivity().findViewById(R.id.tv_month);
        tv_month.setText(android.text.format.DateFormat.format("MMMM yyyy", cal_month));

        ImageButton previous = (ImageButton) getActivity().findViewById(R.id.ib_prev);

        previous.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                setPreviousMonth();
                refreshCalendar();
            }
        });

        ImageButton next = (ImageButton) getActivity().findViewById(R.id.Ib_next);
        next.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                setNextMonth();
                refreshCalendar();

            }
        });


        GridView gridview = (GridView) getActivity().findViewById(R.id.gv_calendar);
        gridview.setAdapter(cal_adapter);
        gridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            public void onItemClick(AdapterView<?> parent, View v,
                                    int position, long id) {

                ((CalendarAdapter) parent.getAdapter()).setSelected(v,position);
                String selectedGridDate = CalendarAdapter.day_string
                        .get(position);

                String[] separatedTime = selectedGridDate.split("-");
                String gridvalueString = separatedTime[2].replaceFirst("^0*","");
                int gridvalue = Integer.parseInt(gridvalueString);

                if ((gridvalue > 10) && (position < 8)) {
                    setPreviousMonth();
                    refreshCalendar();
                } else if ((gridvalue < 7) && (position > 28)) {
                    setNextMonth();
                    refreshCalendar();
                }
                ((CalendarAdapter) parent.getAdapter()).setSelected(v,position);


                ((CalendarAdapter) parent.getAdapter()).getPositionList(selectedGridDate, getActivity());
            }

        });

        return rootView;
    }

    protected void setNextMonth() {
        if (cal_month.get(GregorianCalendar.MONTH) == cal_month
                .getActualMaximum(GregorianCalendar.MONTH)) {
            cal_month.set((cal_month.get(GregorianCalendar.YEAR) + 1),
                    cal_month.getActualMinimum(GregorianCalendar.MONTH), 1);
        } else {
            cal_month.set(GregorianCalendar.MONTH,
                    cal_month.get(GregorianCalendar.MONTH) + 1);
        }

    }

    protected void setPreviousMonth() {
        if (cal_month.get(GregorianCalendar.MONTH) == cal_month
                .getActualMinimum(GregorianCalendar.MONTH)) {
            cal_month.set((cal_month.get(GregorianCalendar.YEAR) - 1),
                    cal_month.getActualMaximum(GregorianCalendar.MONTH), 1);
        } else {
            cal_month.set(GregorianCalendar.MONTH,
                    cal_month.get(GregorianCalendar.MONTH) - 1);
        }

    }

    public void refreshCalendar() {
        cal_adapter.refreshDays();
        cal_adapter.notifyDataSetChanged();
        tv_month.setText(android.text.format.DateFormat.format("MMMM yyyy", cal_month));
    }
}

第二个片段

package com.idkstudios.shiftcalculator.fragments;

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ListView;

import com.idkstudios.shiftcalculator.R;
import com.idkstudios.shiftcalculator.calendar.adapter.AndroidListAdapter;
import com.idkstudios.shiftcalculator.calendar.util.CalendarCollection;

import java.util.ArrayList;

/**
 * Created by Toby on 02/09/2015.
 */
public class HoursListFragment extends Fragment implements View.OnClickListener{

    private ListView lv_android;
    private AndroidListAdapter list_adapter;
    private Button btn_calender;

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

        CalendarCollection.date_collection_arr = new ArrayList<CalendarCollection>();
        CalendarCollection.date_collection_arr.add(new CalendarCollection("2015-04-01","John Birthday"));
        CalendarCollection.date_collection_arr.add(new CalendarCollection("2015-04-04","Client Meeting at 5 p.m."));
        CalendarCollection.date_collection_arr.add(new CalendarCollection("2015-04-06","A Small Party at my office"));
        CalendarCollection.date_collection_arr.add(new CalendarCollection("2015-05-02","Marriage Anniversary"));
        CalendarCollection.date_collection_arr.add(new CalendarCollection("2015-04-11","Live Event and Concert of sonu"));


        getWidget();

        return rootView;
    }

    public void getWidget(){
        btn_calender = (Button) getActivity().findViewById(R.id.btn_calender);
        btn_calender.setOnClickListener(this);

        lv_android = (ListView) getActivity().findViewById(R.id.lv_android);
        list_adapter = new AndroidListAdapter(getActivity(), R.layout.list_item, CalendarCollection.date_collection_arr);
        lv_android.setAdapter(list_adapter);

    }



    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
            case R.id.btn_calender:
                startActivity(new Intent(getActivity(), CalendarFragment.class));

                break;

            default:
                break;
        }

    }
}

最后我还没有实际编码的第三个，

package com.idkstudios.shiftcalculator.fragments;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.idkstudios.shiftcalculator.R;

/**
 * Created by Toby on 02/09/2015.
 */
public class PayFragment extends Fragment {

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

如果您需要，这是Android清单

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.idkstudios.shiftcalculator" >

    <application
        android:allowBackup="true"
        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>
    </application>
</manifest>

这是主要活动的适配器类

package com.idkstudios.shiftcalculator.tab;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;

import com.idkstudios.shiftcalculator.fragments.CalendarFragment;
import com.idkstudios.shiftcalculator.fragments.HoursListFragment;
import com.idkstudios.shiftcalculator.fragments.PayFragment;

/**
 * Created by Toby on 02/09/2015.
 */
public class TabsPagerAdapter extends FragmentPagerAdapter {

    public TabsPagerAdapter(FragmentManager fragmentManager){
        super(fragmentManager);
    }

    @Override
    public Fragment getItem(int index) {
        switch(index){
            case 0:
                return new HoursListFragment();
            case 1:
                return new CalendarFragment();
            case 2:
                return new PayFragment();
        }

        return null;
    }

    @Override
    public int getCount() {
        /**
         * This value is equal to the number of tabs you have in the bar
         */
        return 3;
    }
}

我确实考虑过制定第二个计划。这三个片段都来自一个活动类，所以我将活动类中的代码复制并粘贴到片段中，这可能就是问题所在。我考虑过使用原始的acitivty类，然后从fragment类开始一个新的intent到activity类。但那么片段类的重点是什么呢。我不太确定这个想法是否会起作用。

任何帮助都会得到很多帮助。如果您需要更多代码，请告诉我，我很乐意提供它，无论是一些适配器还是xml代码。

谢谢托比。

Answer 1

HoursListFragment.onClick()有这个错误的陈述：

startActivity(new Intent(getActivity(), CalendarFragment.class));

如您所知，片段不是活动。您的意思是通过MainActivity.class代替CalendarFragment.class吗？

Answer 2

我认为问题是你的viewpager适配器，并且您的MainActivity可以更好地扩展FragmentActivity 因为你想使用片段

然后在MainActivity类中定义三个字段，如下所示

CalendarFragment calenderFragment = new CalendarFragment ();

HoursListFragment hourListFragment = new HoursListFragment ();

PayFragment payFragment = new PayFragment ();

和一个整数作为NUMBER_OF_VIEWPAGER_PAGES 或更短的变量名称，如NUM_PAGE

public static final int NUM_PAGES = 3;

并为您的视图寻呼机制作适配器，如此

private class MyAdapter extends FragmentStatePagerAdapter {
        @Override
        public CharSequence getPageTitle(int position) {
            switch (position) {
                case 0:
                    return tabTitles[0] ;
                case 1:
                    return tabTitles[1] ;
                default:
                    return tabTitles[2] ;
            }

        }


        public MyAdapter(FragmentManager fm) {
            super(fm);
        }


        @Override
        public Fragment getItem(int position) {

            switch (position) {
                case 0:
                    return calenderFragment;
                case 1:
                    return hourListFragment;
                case 2:
                    return payFragment;
                default:
                    return null;
            }

        }


        @Override
        public int getCount() {
            return NUM_PAGES;
        }
}

最后将适配器设置为viewPager

viewPager.setAdapter(new MyAdapter(getSupportFragmentManager()));

Android片段应用错误

2 个答案: