android - 将 ListActivity 转换为 ListFragment

标签 android fragment listactivity android-listfragment

如何将此 ListActivity 更改为 ListFragment..？我在网上寻找了一些有用的资源，并亲自尝试过，但没有成功。 ListFragment 与 ListActivity 有相同的方法吗？请帮忙。提前谢谢大家。

这是我的代码:

import java.util.Locale;
import android.annotation.SuppressLint;
import android.app.ListActivity;
import android.content.Context;
import android.graphics.Color;
import android.os.Build;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SectionIndexer;
import android.widget.TextView;
import android.widget.Toast;

import com.hb.examples.pinnedsection.R;
import com.hb.views.PinnedSectionListView;
import com.hb.views.PinnedSectionListView.PinnedSectionListAdapter;

public class SectionedListActivity extends ListActivity implements OnClickListener {

    static class SimpleAdapter extends ArrayAdapter<Item> implements PinnedSectionListAdapter {

        private static final int[] COLORS = new int[] {
            R.color.green_light, R.color.orange_light,
            R.color.blue_light, R.color.red_light };

        public SimpleAdapter(Context context, int resource, int textViewResourceId) {
            super(context, resource, textViewResourceId);

            final int sectionsNumber = 'Z' - 'A' + 1;
            prepareSections(sectionsNumber);

            int sectionPosition = 0, listPosition = 0;
            for (char i=0; i<sectionsNumber; i++) {
                Item section = new Item(Item.SECTION, String.valueOf((char)('A' + i)));
                section.sectionPosition = sectionPosition;
                section.listPosition = listPosition++;
                onSectionAdded(section, sectionPosition);
                add(section);

                final int itemsNumber = (int) Math.abs((Math.cos(2f*Math.PI/3f * sectionsNumber / (i+1f)) * 25f));
                for (int j=0;j<itemsNumber;j++) {
                    Item item = new Item(Item.ITEM, section.text.toUpperCase(Locale.ENGLISH) + " - " + j);
                    item.sectionPosition = sectionPosition;
                    item.listPosition = listPosition++;
                    add(item);
                }

                sectionPosition++;
            }
        }

        protected void prepareSections(int sectionsNumber) { }
        protected void onSectionAdded(Item section, int sectionPosition) { }

        @Override public View getView(int position, View convertView, ViewGroup parent) {
            TextView view = (TextView) super.getView(position, convertView, parent);
            view.setTextColor(Color.DKGRAY);
            view.setTag("" + position);
            Item item = getItem(position);
            if (item.type == Item.SECTION) {
                //view.setOnClickListener(SectionedListActivity.this);
                view.setBackgroundColor(parent.getResources().getColor(COLORS[item.sectionPosition % COLORS.length]));
            }
            return view;
        }

        @Override public int getViewTypeCount() {
            return 2;
        }

        @Override public int getItemViewType(int position) {
            return getItem(position).type;
        }

        @Override
        public boolean isItemViewTypePinned(int viewType) {
            return viewType == Item.SECTION;
        }

    }

    static class FastScrollAdapter extends SimpleAdapter implements SectionIndexer {

        private Item[] sections;

        public FastScrollAdapter(Context context, int resource, int textViewResourceId) {
            super(context, resource, textViewResourceId);
        }

        @Override protected void prepareSections(int sectionsNumber) {
            sections = new Item[sectionsNumber];
        }

        @Override protected void onSectionAdded(Item section, int sectionPosition) {
            sections[sectionPosition] = section;
        }

        @Override public Item[] getSections() {
            return sections;
        }

        @Override public int getPositionForSection(int section) {
            if (section >= sections.length) {
                section = sections.length - 1;
            }
            return sections[section].listPosition;
        }

        @Override public int getSectionForPosition(int position) {
            if (position >= getCount()) {
                position = getCount() - 1;
            }
            return getItem(position).sectionPosition;
        }

    }

    static class Item {

        public static final int ITEM = 0;
        public static final int SECTION = 1;

        public final int type;
        public final String text;

        public int sectionPosition;
        public int listPosition;

        public Item(int type, String text) {
            this.type = type;
            this.text = text;
        }

        @Override public String toString() {
            return text;
        }

    }

    private boolean hasHeaderAndFooter;
    private boolean isFastScroll;
    private boolean addPadding;
    private boolean isShadowVisible = true;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if (savedInstanceState != null) {
            isFastScroll = savedInstanceState.getBoolean("isFastScroll");
            addPadding = savedInstanceState.getBoolean("addPadding");
            isShadowVisible = savedInstanceState.getBoolean("isShadowVisible");
            hasHeaderAndFooter = savedInstanceState.getBoolean("hasHeaderAndFooter");
        }
        initializeHeaderAndFooter();
        initializeAdapter();
        initializePadding();
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putBoolean("isFastScroll", isFastScroll);
        outState.putBoolean("addPadding", addPadding);
        outState.putBoolean("isShadowVisible", isShadowVisible);
        outState.putBoolean("hasHeaderAndFooter", hasHeaderAndFooter);
    }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        Item item = (Item) getListView().getAdapter().getItem(position);
        if (item != null) {
            Toast.makeText(this, "Item " + position + ": " + item.text, Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "Item " + position, Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        menu.getItem(0).setChecked(isFastScroll);
        menu.getItem(1).setChecked(addPadding);
        menu.getItem(2).setChecked(isShadowVisible);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_fastscroll:
                isFastScroll = !isFastScroll;
                item.setChecked(isFastScroll);
                initializeAdapter();
                break;
            case R.id.action_addpadding:
                addPadding = !addPadding;
                item.setChecked(addPadding);
                initializePadding();
                break;
            case R.id.action_showShadow:
                isShadowVisible = !isShadowVisible;
                item.setChecked(isShadowVisible);
                ((PinnedSectionListView)getListView()).setShadowVisible(isShadowVisible);
                break;
            case R.id.action_showHeaderAndFooter:
                hasHeaderAndFooter = !hasHeaderAndFooter;
                item.setChecked(hasHeaderAndFooter);
                initializeHeaderAndFooter();
                break;
        }
        return true;
    }

    private void initializePadding() {
        float density = getResources().getDisplayMetrics().density;
        int padding = addPadding ? (int) (16 * density) : 0;
        getListView().setPadding(padding, padding, padding, padding);
    }

    private void initializeHeaderAndFooter() {
        setListAdapter(null);
        if (hasHeaderAndFooter) {
            ListView list = getListView();

            LayoutInflater inflater = LayoutInflater.from(this);
            TextView header1 = (TextView) inflater.inflate(android.R.layout.simple_list_item_1, list, false);
            header1.setText("First header");
            list.addHeaderView(header1);

            TextView header2 = (TextView) inflater.inflate(android.R.layout.simple_list_item_1, list, false);
            header2.setText("Second header");
            list.addHeaderView(header2);

            TextView footer = (TextView) inflater.inflate(android.R.layout.simple_list_item_1, list, false);
            footer.setText("Single footer");
            list.addFooterView(footer);
        }
        initializeAdapter();
    }

    @SuppressLint("NewApi")
    private void initializeAdapter() {
        getListView().setFastScrollEnabled(isFastScroll);
        if (isFastScroll) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                getListView().setFastScrollAlwaysVisible(true);
            }
            setListAdapter(new FastScrollAdapter(this, android.R.layout.simple_list_item_1, android.R.id.text1));
        } else {
            setListAdapter(new SimpleAdapter(this, android.R.layout.simple_list_item_1, android.R.id.text1));
        }
    }

    @Override
    public void onClick(View v) {
        Toast.makeText(this, "Item: " + v.getTag() , Toast.LENGTH_SHORT).show();
    }

}

我找到了一种转换为 ListFragment 的方法

代码:

public static class PlanetFragment extends Fragment {
        public static final String ARG_PLANET_NUMBER = "planet_number";

        public PlanetFragment() {
            // Empty constructor required for fragment subclasses
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_planet, container, false);
            int i = getArguments().getInt(ARG_PLANET_NUMBER);
            String planet = getResources().getStringArray(R.array.planets_array)[i];

            int imageId = getResources().getIdentifier(planet.toLowerCase(Locale.getDefault()),
                            "drawable", getActivity().getPackageName());
            ((ImageView) rootView.findViewById(R.id.image)).setImageResource(imageId);
            getActivity().setTitle(planet);
            return rootView;
        }
    }

    public static class PinnedListView extends ListFragment implements OnClickListener {
        private boolean hasHeaderAndFooter;
        private boolean isFastScroll;
        private boolean addPadding;
        private boolean isShadowVisible = true;

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            return inflater.inflate(R.layout.custom_view,container, false);
        }

        @Override
        public void onActivityCreated(Bundle savedInstanceState) {
            super.onActivityCreated(savedInstanceState);
            if (savedInstanceState != null) {
                isFastScroll = savedInstanceState.getBoolean("isFastScroll");
                addPadding = savedInstanceState.getBoolean("addPadding");
                isShadowVisible = savedInstanceState.getBoolean("isShadowVisible");
                hasHeaderAndFooter = savedInstanceState.getBoolean("hasHeaderAndFooter");
            }
            initializeHeaderAndFooter();
            initializeAdapter();
            initializePadding();
        }

        @Override
        public void onSaveInstanceState(Bundle outState) {
            super.onSaveInstanceState(outState);
            outState.putBoolean("isFastScroll", isFastScroll);
            outState.putBoolean("addPadding", addPadding);
            outState.putBoolean("isShadowVisible", isShadowVisible);
            outState.putBoolean("hasHeaderAndFooter", hasHeaderAndFooter);
        }

        @Override
        public void onListItemClick(ListView l, View v, int position, long id) {
            Item item = (Item) getListView().getAdapter().getItem(position);
            if (item != null) {
                Toast.makeText(getActivity(), "Item " + position + ": " + item.text, Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(getActivity(), "Item " + position, Toast.LENGTH_SHORT).show();
            }
        }

        public boolean onCreateOptionsMenu(Menu menu) {
            getActivity().getMenuInflater().inflate(R.menu.main, menu);
            menu.getItem(0).setChecked(isFastScroll);
            menu.getItem(1).setChecked(addPadding);
            menu.getItem(2).setChecked(isShadowVisible);
            return true;
        }

        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            switch (item.getItemId()) {
                case R.id.action_fastscroll:
                    isFastScroll = !isFastScroll;
                    item.setChecked(isFastScroll);
                    initializeAdapter();
                    break;
                case R.id.action_addpadding:
                    addPadding = !addPadding;
                    item.setChecked(addPadding);
                    initializePadding();
                    break;
                case R.id.action_showShadow:
                    isShadowVisible = !isShadowVisible;
                    item.setChecked(isShadowVisible);
                    ((PinnedSectionListView)getListView()).setShadowVisible(isShadowVisible);
                    break;
                case R.id.action_showHeaderAndFooter:
                    hasHeaderAndFooter = !hasHeaderAndFooter;
                    item.setChecked(hasHeaderAndFooter);
                    initializeHeaderAndFooter();
                    break;
            }
            return true;
        }

        private void initializePadding() {
            float density = getResources().getDisplayMetrics().density;
            int padding = addPadding ? (int) (16 * density) : 0;
            getListView().setPadding(padding, padding, padding, padding);
        }

        private void initializeHeaderAndFooter() {
            setListAdapter(null);
            if (hasHeaderAndFooter) {
                ListView list = getListView();

                LayoutInflater inflater = LayoutInflater.from(getActivity());
                TextView header1 = (TextView) inflater.inflate(android.R.layout.simple_list_item_1, list, false);
                header1.setText("First header");
                list.addHeaderView(header1);

                TextView header2 = (TextView) inflater.inflate(android.R.layout.simple_list_item_1, list, false);
                header2.setText("Second header");
                list.addHeaderView(header2);

                TextView footer = (TextView) inflater.inflate(android.R.layout.simple_list_item_1, list, false);
                footer.setText("Single footer");
                list.addFooterView(footer);
            }
            initializeAdapter();
        }

        @SuppressLint("NewApi")
        private void initializeAdapter() {
            getListView().setFastScrollEnabled(isFastScroll);
            if (isFastScroll) {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                    getListView().setFastScrollAlwaysVisible(true);
                }
                setListAdapter(new FastScrollAdapter(getActivity(), android.R.layout.simple_list_item_1, android.R.id.text1));
            } else {
                setListAdapter(new SimpleAdapter(getActivity(), android.R.layout.simple_list_item_1, android.R.id.text1));
            }
        }

        @Override
        public void onClick(View v) {
            Toast.makeText(getActivity(), "Item: " + v.getTag() , Toast.LENGTH_SHORT).show();
        }
    }

最佳答案

ListFragment 将为您提供所需的一切，如 ListActivity。您需要创建一个新的 Activity(主 Activity)来扩展 FragmentActivity 并将 ListFragment 作为不同的类，然后将 Fragment 添加到 Activity 中。如果您不知道如何执行此操作，我强烈建议您阅读The Fragments Tutorial Here .

关于android - 将 ListActivity 转换为 ListFragment，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/22186048/

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