导航类型：Tabs + Swype

Question

几周前我一直在搜索如何使用我的应用程序的标签创建一个友好的设计。我发现了如何使用 TabHost 但我也读到它已被弃用了所以有一天我意识到Eclipse在你创建一个名为的新的Android应用程序项目时提供了一个基础：导航类型：操作栏（带有viewPager）的

问题是：您是否有任何可以了解其实施的教程或网站？你会建议我在未来的应用中使用这个基础吗？为什么？

我很难理解每一段代码的含义和做法，互联网并没有提供太多关于此的信息。

以下是我称之为Inicio的主要活动的代码：

import java.util.Locale;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.view.ViewPager;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class Inicio extends ActionBarActivity implements ActionBar.TabListener {

/**
 * The {@link android.support.v4.view.PagerAdapter} that will provide
 * fragments for each of the sections. We use a
 * {@link FragmentPagerAdapter} derivative, which will keep every
 * loaded fragment in memory. If this becomes too memory intensive, it
 * may be best to switch to a
 * {@link android.support.v4.app.FragmentStatePagerAdapter}.
 */
SectionsPagerAdapter mSectionsPagerAdapter;

/**
 * The {@link ViewPager} that will host the section contents.
 */
ViewPager mViewPager;

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

    // Set up the action bar.
    final ActionBar actionBar = getSupportActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    // Create the adapter that will return a fragment for each of the three
    // primary sections of the activity.
    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

    // Set up the ViewPager with the sections adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    // When swiping between different sections, select the corresponding
    // tab. We can also use ActionBar.Tab#select() to do this if we have
    // a reference to the Tab.
    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
        @Override
        public void onPageSelected(int position) {
            actionBar.setSelectedNavigationItem(position);
        }
    });

    // For each of the sections in the app, add a tab to the action bar.
    for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
        // Create a tab with text corresponding to the page title defined by
        // the adapter. Also specify this Activity object, which implements
        // the TabListener interface, as the callback (listener) for when
        // this tab is selected.
        actionBar.addTab(
                actionBar.newTab()
                .setText(mSectionsPagerAdapter.getPageTitle(i))
                .setTabListener(this));
    }
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {

    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.inicio, menu);
    return true;
}

@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();
    switch(id){
    case R.id.action_settings:

        break;
    case R.id.action_share:

        break;

    default:
        break;
    }

    return super.onOptionsItemSelected(item);
}

@Override
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
    // When the given tab is selected, switch to the corresponding page in
    // the ViewPager.
    mViewPager.setCurrentItem(tab.getPosition());
}

@Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}

@Override
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}

/**
 * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
 * one of the sections/tabs/pages.
 */
public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

    @Override
    public Fragment getItem(int position) {
        // getItem is called to instantiate the fragment for the given page.
        // Return a PlaceholderFragment (defined as a static inner class below).
        return PlaceholderFragment.newInstance(position + 1);
    }

    @Override
    public int getCount() {
        // Show 3 total pages.
        return 3;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        Locale l = Locale.getDefault();
        switch (position) {
        case 2:
            return getString(R.string.tab_consumolitros).toUpperCase(l);
        case 1:
            return getString(R.string.tab_consumonormal).toUpperCase(l);
        case 0:
            return getString(R.string.tab_consumoviajes).toUpperCase(l);
        }
        return null;
    }
}

/**
 * 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_inicio, container, false);
        TextView textView = (TextView) rootView.findViewById(R.id.section_label);
        textView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    }
}

}

这里的viewPager名为activity_main：

<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.myexample.MainActivity" />

这里的布局叫做fragment_main：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.myexample.Inicio$PlaceholderFragment" >

<TextView
    android:id="@+id/section_label"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

</RelativeLayout>

提前致谢

Answer 1

半年前我遇到了同样的问题，谷歌毕竟不是那么糟糕。 我真的很喜欢http://developer.android.com/training/implementing-navigation/lateral.html它也回答了为什么你应该使用新的，推荐的实现应用程序导航的方法。 我希望这能有所帮助。为了理解代码，我想更多地阅读关于＆＃34;片段＆＃34;会有所帮助。 所以回到你的问题：问题是：你会建议我在未来的应用中使用这个基础吗？为什么？ 我建议使用它。因为它是在应用程序中实现简单有效导航的推荐方法。原因是多种多样的，但我使用它的主要原因是导航非常直观的触摸屏＆＃34;用户（广泛使用，因此被用户广为人知）并且它很简单！