类型不匹配无法将主要活动转换为片段

时间:2014-03-04 14:26:18

标签: java android android-fragments

我正在使用标签布局但是我在尝试将标签链接到我的活动时收到错误。我是新手,我可能在这里使用了错误的术语,但我希望你明白我的意思它意味着什么?

TabPagerAdapter.Java

package com.learn2crack.tab;

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



public class TabPagerAdapter extends FragmentStatePagerAdapter {
    public TabPagerAdapter(FragmentManager fm) {
        super(fm);
        // TODO Auto-generated constructor stub
    }


    @Override
    public Fragment getItem(int i) {
        switch (i) {
        case 0:
            //Fragement for Android Tab
            return new MainActivity1();
        case 1:
           //Fragment for Ios Tab
            return new Maps();
       // case 2:
            //Fragment for Windows Tab
            //return new Scanner();
        }
        return null;

    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return 3; //No of Tabs
    }


    }

MainActivity1.java

package com.learn2crack.tab;

import android.app.Activity;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.ListFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;



     interface OnHeadlineSelectedListener {
         /** Called by HeadlinesFragment when a list item is selected */
         public void onArticleSelected(int position);
     }
     public class MainActivity1 extends FragmentActivity implements OnHeadlineSelectedListener {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.rooms_view);

        // Check whether the activity is using the layout version with
        // the fragment_container FrameLayout. If so, we must add the first fragment
        if (findViewById(R.id.fragment_container) != null) {

            // However, if we're being restored from a previous state,
            // then we don't need to do anything and should return or else
            // we could end up with overlapping fragments.
            if (savedInstanceState != null) {
                return;
            }

            // Create an instance of ExampleFragment
            HeadlinesFragment firstFragment = new HeadlinesFragment();

            // In case this activity was started with special instructions from an Intent,
            // pass the Intent's extras to the fragment as arguments
            firstFragment.setArguments(getIntent().getExtras());

            // Add the fragment to the 'fragment_container' FrameLayout
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.fragment_container, firstFragment).commit();
        }
    }

    public void onArticleSelected(int position) {
        // The user selected the headline of an article from the HeadlinesFragment

        // Capture the article fragment from the activity layout
        ArticleFragment articleFrag = (ArticleFragment)
                getSupportFragmentManager().findFragmentById(R.id.Software);

        if (articleFrag != null) {
            // If article frag is available, we're in two-pane layout...

            // Call a method in the ArticleFragment to update its content
            articleFrag.updateArticleView(position);

        } else {
            // If the frag is not available, we're in the one-pane layout and must swap frags...

            // Create fragment and give it an argument for the selected article
            ArticleFragment newFragment = new ArticleFragment();
            Bundle args = new Bundle();
            args.putInt(ArticleFragment.ARG_POSITION, position);
            newFragment.setArguments(args);
            FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();

            // Replace whatever is in the fragment_container view with this fragment,
            // and add the transaction to the back stack so the user can navigate back
            transaction.replace(R.id.fragment_container, newFragment);
            transaction.addToBackStack(null);

            // Commit the transaction
            transaction.commit();
        }
    }

    public class ArticleFragment extends Fragment {
        final static String ARG_POSITION = "position";
        int mCurrentPosition = -1;

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, 
            Bundle savedInstanceState) {

            // If activity recreated (such as from screen rotate), restore
            // the previous article selection set by onSaveInstanceState().
            // This is primarily necessary when in the two-pane layout.
            if (savedInstanceState != null) {
                mCurrentPosition = savedInstanceState.getInt(ARG_POSITION);
            }

            // Inflate the layout for this fragment
            return inflater.inflate(R.layout.sofware_view, container, false);
        }

        @Override
        public void onStart() {
            super.onStart();

            // During startup, check if there are arguments passed to the fragment.
            // onStart is a good place to do this because the layout has already been
            // applied to the fragment at this point so we can safely call the method
            // below that sets the article text.
            Bundle args = getArguments();
            if (args != null) {
                // Set article based on argument passed in
                updateArticleView(args.getInt(ARG_POSITION));
            } else if (mCurrentPosition != -1) {
                // Set article based on saved instance state defined during onCreateView
                updateArticleView(mCurrentPosition);
            }
        }

        public void updateArticleView(int position) {
            TextView article = (TextView) getActivity().findViewById(R.id.Software);
            article.setText(Rooms[position]);
            mCurrentPosition = position;
        }

        @Override
        public void onSaveInstanceState(Bundle outState) {
            super.onSaveInstanceState(outState);

            // Save the current article selection in case we need to recreate the fragment
            outState.putInt(ARG_POSITION, mCurrentPosition);
        }
    }

    public class HeadlinesFragment extends ListFragment {
        OnHeadlineSelectedListener mCallback;




        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            // We need to use a different list item layout for devices older than Honeycomb
            int layout = Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB ?
                    android.R.layout.simple_list_item_activated_1 : android.R.layout.simple_list_item_1;

            // Create an array adapter for the list view, using the Ipsum headlines array
            setListAdapter(new ArrayAdapter<String>(getActivity(), layout, Software));
        }

        @Override
        public void onStart() {
            super.onStart();

            // When in two-pane layout, set the listview to highlight the selected list item
            // (We do this during onStart because at the point the listview is available.)
            if (getFragmentManager().findFragmentById(R.id.Software) != null) {
                getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);
            }
        }

        @Override
        public void onAttach(Activity activity) {
            super.onAttach(activity);

            // This makes sure that the container activity has implemented
            // the callback interface. If not, it throws an exception.
            try {
                mCallback = (OnHeadlineSelectedListener) activity;
            } catch (ClassCastException e) {
                throw new ClassCastException(activity.toString()
                        + " must implement OnHeadlineSelectedListener");
            }
        }

        @Override
        public void onListItemClick(ListView l, View v, int position, long id) {
            // Notify the parent activity of selected item
            mCallback.onArticleSelected(position);

            // Set the item as checked to be highlighted when in two-pane layout
            getListView().setItemChecked(position, true);
        }
    }

    ArrayAdapter<String> adapter;




    static String Software[] = {
            "3D Studio Max 2014",
            "Adobe Creative Suite 6",
            "Agilent Agent",
            "Android SDK",
            "Audacity",
            "C Map Tools",
            "Cedar and Easy 68k",
            "Context",
            "CryEngine 3",
            "Derive V5.0",
            "Dreamweaver CS6",
            "Eclipse",
            "Face Modeller",
            "Flash CS6",
            "Image J",
            "Linux",
            "Matlab R2012A (Computing Toolbase)",
            "Matlab R2012A (Maths)",
            "Microsoft Project",
            "Microsoft SQL Sever Lite",
            "MinecraftEDU",
            "MiniTab 16",
            "MonoGame",
            "NetBeans 7.3.1",
            "Office 2013",
            "Oracle Client",
            "Photoshop CS6",
            "Premiere CS6",
            "Python 3.3.2",
            "QT 5.1",
            "R-Studio",
            "Rational Architect",
            "Steam",
            "SWI Pro Log",
            "Unreal UDK",
            "Visio 2012",
            "Visual Studio 2012",
            "Win A&D 7 Desktop",
            "Windows Mobile SDK",
            "Weka ML",
            "XNA Game Studio"};

   static  String Rooms []= { "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",
            "MEA 27\n MEA 34\n",




    };
}

有没有人知道如何解决这个问题?

2 个答案:

答案 0 :(得分:0)

getItem必须返回Fragment而不是Activity

答案 1 :(得分:0)

getItem方法必须返回一个Fragment。您的MainActivity1扩展了FragmentActivity(一个Activity的执行)。你不能这样做。每个页面都必须是片段,没有别的。

@Override
public Fragment getItem(int i) {
    // this must return a Fragment!
}

在您的应用中,您应该:

  1. 活动/ FragmentActivity
  2. 您的适配器
  3. AndroidTapPageFragment(extends Fragment)
  4. IOSTapPageFragment(extends Fragment)
  5. WindowsTapPageFragment(extends Fragment)
  6. 如果您的网页具有相同的布局/功能,您可以为Android,IOS和Windows标签创建一个Fragment OSPageFragment。