7

我正在使用 ViewPager 允许用户在片段之间滑动。

如何在屏幕上添加每个片段的标题？

package com.multi.andres;

import java.util.List;
import java.util.Vector;

import com.viewpagerindicator.TitlePageIndicator;
import com.viewpagerindicator.TitleProvider;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;

public class ViewPagerFragment extends FragmentActivity{

    private PagerAdapter mPagerAdapter; //contiene el pager adapter
    private static String[] titulosPaginas = { "APP 1", "APP 2" };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        super.setContentView(R.layout.lcmeter); //layout que contiene el ViewPager

        initialisePaging(); //inicializo las paginas
    }

    private void initialisePaging() {

        List<Fragment> fragments = new Vector<Fragment>();
        fragments.add(Fragment.instantiate(this, FragmentPrueba1.class.getName()));
        fragments.add(Fragment.instantiate(this, FragmentPrueba2.class.getName()));
        this.mPagerAdapter  = new PagerAdapter(super.getSupportFragmentManager(), fragments);

        ViewPager pager = (ViewPager)super.findViewById(R.id.pager);
        pager.setAdapter(this.mPagerAdapter);

        //Agrega los titulos
        TitlePageIndicator titleIndicator = (TitlePageIndicator) findViewById(R.id.titulos);    //layout XML
        titleIndicator.setViewPager(pager);
    }

    /** *************************************************************************************************
    /** Clase:   public class PagerAdapter extends FragmentPagerAdapter implements TitleProvider
    /** Notas:   extends FragmentPagerAdapter permite el uso de las paginas de ViewPager pero con Fragments
    /**          implements TitleProvider permite el uso de los titulos en las paginas
    /** Funcion: crea paginas por las cuales deslizarse horizontalmente las cuales son usadas
    ****************************************************************************************************/
    public class PagerAdapter extends FragmentPagerAdapter implements TitleProvider {

        private List<Fragment> fragments;

        public String getTitle(int position) {
            // TODO Auto-generated method stub
            return titulosPaginas[position];    // titulo de la pagina
        }

        public PagerAdapter(FragmentManager fm, List<Fragment> fragments) {
            super(fm);
            this.fragments = fragments;
        }

        @Override
        public int getCount() {
            return this.fragments.size();
        }

        @Override
        public Fragment getItem(int position) {
            return this.fragments.get(position);
        }

    }

}

但它没有显示 ViewPager 的标题，我不知道为什么。我以前使用带有标题的 ViewPager，但没有使用片段，现在我无法使标题正常工作。

4

4 回答 4

25

您还可以使用 Jake Wharton 的ViewPagerIndicator库来获得所需的效果。ViewPagerDavek804 的答案也有效，但它需要您参考整个 ActionBarSherlock 库，如果您只需要支持自定义/样式标题的，那么这不是可取的。

设置它以使其正常工作只需要编写一点点 XML，ViewPager在 your 中初始化Activity，并实现一个FragmentAdapter(which extends FragmentPagerAdapter implements TitleProvider) 来指定哪些页面保存 which Fragments。

  1. XML 布局

    <LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.viewpagerindicator.TabPageIndicator
        android:id="@+id/titles"
        android:layout_height="wrap_content"
        android:layout_width="match_parent"/>

    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"/>

</LinearLayout>

  2. 在你的初始化Activity

    //Set the pager with an adapter
ViewPager pager = (ViewPager)findViewById(R.id.pager);
pager.setAdapter(new CustomAdapter(getSupportFragmentManager()));

//Bind the title indicator to the adapter
TitlePageIndicator titleIndicator = (TitlePageIndicator) findViewById(R.id.titles);
titleIndicator.setViewPager(pager);

  3. 实施一个CustomFragmentAdapter

    public static class CustomFragmentAdapter extends FragmentPagerAdapter 
        implements TitleProvider {

        public static final int POSITION_PAGE_1 = 0;
        public static final int POSITION_PAGE_2 = 1;
        public static final int POSITION_PAGE_3 = 2;

        private static final String[] TITLES = new String[] { 
            "Title 1", 
            "Title 2", 
            "Title 3" 
        };

        public static final int NUM_TITLES = TITLES.length;

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

        @Override
        public Fragment getItem(int position) {     
            switch (position) {
            case POSITION_TITLE_1:              
                return PageOneFragment.newInstance();
            case POSITION_TITLE_2: 
                return PageTwoFragment.newInstance();
            case POSITION_TITLE_3:
                return PageThreeFragment.newInstance();         
            }
            return null;
        }

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

        @Override
        public String getTitle(int position) {
            return TITLES[position % NUM_TITLES].toUpperCase();
        }
    }

编辑：

该ViewPagerIndicator库支持标题功能：

  1. TitlePageIndicator

    标题页指示器

  2. TabPageIndicator

    标签页指示器

  3. CirclePageIndicator

    圆形页面指示器

于 2012-04-06T04:53:34.427 回答
11

或者如果您不喜欢使用第三方库，您可以使用支持 v4 PagerTabStrip 类。例如：

<android.support.v4.view.ViewPager
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="0px"
    android:layout_weight="1">
    <android.support.v4.view.PagerTabStrip
        android:id="@+id/pts_main"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</android.support.v4.view.ViewPager>

并在 PagerAdapter 覆盖 getPageTitle 方法：

public static class MyAdapter extends FragmentPagerAdapter  {
    ...
    @Override
    public CharSequence getPageTitle(int position) {
        return String.valueOf(position);
    }
}

您可以从如下代码访问 xml 元素：

protected void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.pager);
    ...
    mAdapter = new MyAdapter(getSupportFragmentManager());
    // Add custom adapter
    mPager = (ViewPager)findViewById(R.id.pager);
    mPager.setAdapter(mAdapter);

    // Get PagerTabStrip
    PagerTabStrip strip = (PagerTabStrip) findViewById(R.id.pts_main);
    strip.setDrawFullUnderline(false);
    ...

我希望它对某人有帮助

于 2014-06-18T10:43:09.817 回答
0

在我说 SherlockFragmentActivity 的地方，你可以只拥有 FragmentActivity。getSupportActionBar 可以是 getActionBar()。

public class Polling extends SherlockFragmentActivity implements OnMenuItemClickListener {
    private ViewPager mViewPager;
    private TabsAdapter mTabsAdapter;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mViewPager = new ViewPager(this);
        mViewPager.setId(R.id.pager);
        setContentView(mViewPager);
        bar = getSupportActionBar();
        bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        bar.setDisplayShowTitleEnabled(false);
        bar.setDisplayShowHomeEnabled(false);
        mTabsAdapter = new TabsAdapter(this, mViewPager);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.login),
                LoginFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.economics),
                EconFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.elections),
                ElectionsFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.politics),
                PoliticsFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.science),
                ScienceFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.finance),
                FinanceFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.religion),
                ReligionFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.military),
                MilitaryFragment.class, null);
        mTabsAdapter.addTab(bar.newTab().setText(R.string.international),
                InternationalFragment.class, null); 
    }

    public static class TabsAdapter extends FragmentPagerAdapter
    implements ActionBar.TabListener, ViewPager.OnPageChangeListener {
        private final Context mContext;
        private final ActionBar mActionBar;
        private final ViewPager mViewPager;
        private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();

        static final class TabInfo {
            private final Class<?> clss;
            private final Bundle args;

            TabInfo(Class<?> _class, Bundle _args) {
                clss = _class;
                args = _args;
            }
        }

        public TabsAdapter(SherlockFragmentActivity activity, ViewPager pager) {
            super(activity.getSupportFragmentManager());
            mContext = activity;
            mActionBar = activity.getSupportActionBar();
            mViewPager = pager;
            mViewPager.setAdapter(this);
            mViewPager.setOnPageChangeListener(this);
        }

        public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
            TabInfo info = new TabInfo(clss, args);
            tab.setTag(info);
            tab.setTabListener(this);
            mTabs.add(info);
            mActionBar.addTab(tab);
            notifyDataSetChanged();
        }

        public int getCount() {
            return mTabs.size();
        }

        public SherlockFragment getItem(int position) {
            TabInfo info = mTabs.get(position);
            return (SherlockFragment)Fragment.instantiate(mContext, info.clss.getName(), info.args);
        }

        public void onPageSelected(int position) {
            mActionBar.setSelectedNavigationItem(position);
        }
        public void onPageScrollStateChanged(int state) {}
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {}

        public void onTabSelected(Tab tab, FragmentTransaction ft) {
            mViewPager.setCurrentItem(tab.getPosition());
            //Log.v(TAG, "clicked");
            Object tag = tab.getTag();
            for (int i=0; i<mTabs.size(); i++) {
                if (mTabs.get(i) == tag) {
                    mViewPager.setCurrentItem(i);
                }
            }
        }
        public void onTabUnselected(Tab tab, FragmentTransaction ft) {}
        public void onTabReselected(Tab tab, FragmentTransaction ft) {}
        public void onTabReselected(Tab tab, android.app.FragmentTransaction ft) {}
        public void onTabUnselected(Tab tab, android.app.FragmentTransaction ft) {}
    }
}
于 2012-04-06T00:52:51.843 回答
0

@Alex Lockwood 谢谢你 :) 我还有一个问题：/ 这是我的 XML：

lcmeter.xml

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

    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >
    </android.support.v4.view.ViewPager>

    <com.viewpagerindicator.TitlePageIndicator
        android:id="@+id/titulos"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

如果在“android.support.v4.view.ViewPager”之前放置“TitlePageIndicator”，则在第一篇文章中使用我的原始代码，我可以看到标题，但我不能只点击标题更改页面并且我的片段没有显示，而是显示XML 这样我可以浏览我的片段，但我看不到标题：/。我以这种方式尝试了whit构造函数：

package com.multi.andres;

import java.util.List;
import java.util.Vector;

import com.viewpagerindicator.TitlePageIndicator;
import com.viewpagerindicator.TitleProvider;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;

public class ViewPagerFragment extends FragmentActivity{

    private PagerAdapter mPagerAdapter; //contiene el pager adapter
    String[] titulosPaginas = { "APP 1", "APP 2" };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        super.setContentView(R.layout.lcmeter); //layout que contiene el ViewPager

        initialisePaging(); //inicializo las paginas
    }

    private void initialisePaging() {

        List<Fragment> fragments = new Vector<Fragment>();
        fragments.add(Fragment.instantiate(this, FragmentPrueba1.class.getName()));
        fragments.add(Fragment.instantiate(this, FragmentPrueba2.class.getName()));
        this.mPagerAdapter  = new PagerAdapter(super.getSupportFragmentManager(), fragments);

        ViewPager pager = (ViewPager)super.findViewById(R.id.pager);
        pager.setAdapter(this.mPagerAdapter);

        //Agrega los titulos
        TitlePageIndicator titleIndicator = (TitlePageIndicator) findViewById(R.id.titulos);    //layout XML
        titleIndicator.setViewPager(pager);
    }

    /** *************************************************************************************************
    /** Clase:   public class PagerAdapter extends FragmentPagerAdapter implements TitleProvider
    /** Notas:   extends FragmentPagerAdapter permite el uso de las paginas de ViewPager pero con Fragments
    /**          implements TitleProvider permite el uso de los titulos en las paginas
    /** Funcion: crea paginas por las cuales deslizarse horizontalmente las cuales son usadas
    ****************************************************************************************************/
    public class PagerAdapter extends FragmentPagerAdapter implements TitleProvider {

        private List<Fragment> fragments;

        public String getTitle(int position) {
            // TODO Auto-generated method stub
            return titulosPaginas[position];    // titulo de la pagina
        }

        public PagerAdapter(FragmentManager fm, List<Fragment> fragments) {
            super(fm);
            this.fragments = fragments;
        }

        @Override
        public int getCount() {
            return this.fragments.size();
        }

        @Override
        public Fragment getItem(int position) {
            try {
                FragmentPrueba1.class.newInstance();
            } catch (InstantiationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return this.fragments.get(position);
        }

    }

}

但是当我打开应用程序时，我有一个 FC。这是我的片段两者都相等：

package com.multi.andres;

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.LinearLayout;

public class FragmentPrueba1 extends Fragment {

    FragmentPrueba1 (){

    }

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

        return (LinearLayout)inflater.inflate(R.layout.prueba1, container, false);

    }

}

它是 XML 片段：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" 
    android:background="#FF0000" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Numero 1 !!" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Esto es un boton XD" />

</LinearLayout>

我已经阅读了有关 Fragments 的信息，但我无法获得带有标题的 Fragments，这没有任何意义：/ 我是新手，但我正在学习，对我来说非常复杂，这种事情非常感谢你的帮助，我真的很感激:)

编辑：

我想我已经找到了问题所在，它不在 Java 代码上，问题出在 XML 文件 ViewPager 上：

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

    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >
    </android.support.v4.view.ViewPager>

    <com.viewpagerindicator.TitlePageIndicator
        android:id="@+id/titulos"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

这似乎“克服”了标题，因为如果我使用在 android.support.v4.view.ViewPager 上添加 android:layout_weight="1" 的 Google 示例的 XML 文件，我可以在屏幕底部看到标题，不是在顶部而是一个进步:)

于 2012-04-07T00:52:42.460 回答