ActionBar + ViewPager(PagerSlidingTabStrip)

之后是activity_main的代码：

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

    <com.francis.changtravels.utils.PagerSlidingTabStrip
        android:id="@+id/tabs"
        android:layout_width="match_parent"
        android:layout_height="40dp" />


        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/tabs" />

</RelativeLayout>

接着创建TravelsFragment、SubjectFragment、DestinationFragment，分别相应着游记、专题、目的地这三个界面。Fragment中仅仅需放置一个TextView用于表示这个界面就可以，TravesFragment（SubjectFragment、DestinationFragment就不说啦）例如以下所看到的：

package com.francis.changtravels.fragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;
import android.widget.TextView;
import com.francis.changtravels.R;
/**
 * Created by Francis on 14-9-18.
 */
public class TravelsFragment extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.photo_wall_falls_demo,container,false);
        return rootView;
    }
}

最后改动MainActivity中的代码。增加PagerSlidingTabStrip的配置。例如以下所看到的：

package com.francis.changtravels.activity;


import java.lang.reflect.Field;
import java.lang.reflect.Method;

import android.graphics.Color;
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;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.Menu;
import android.view.MenuItem;
import android.view.ViewConfiguration;
import android.view.Window;

import com.francis.changtravels.utils.PagerSlidingTabStrip;
import com.francis.changtravels.fragment.DestinationFragment;
import com.francis.changtravels.R;
import com.francis.changtravels.fragment.SubjectFragment;
import com.francis.changtravels.fragment.TravelsFragment;


public class MainActivity extends FragmentActivity {

    /**
     * 游记界面的Fragment
     */
    private TravelsFragment travelsFragment;

    /**
     * 专题界面的Fragment
     */
    private SubjectFragment subjectFragment;

    /**
     * 目的地界面的Fragment
     */
    private DestinationFragment destinationFragment;

    /**
     * PagerSlidingTabStrip的实例
     */
    private PagerSlidingTabStrip tabs;

    /**
     * 获取当前屏幕的密度
     */
    private DisplayMetrics dm;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setOverflowShowingAlways();
        dm = getResources().getDisplayMetrics();
        ViewPager pager = (ViewPager) findViewById(R.id.pager);
        tabs = (PagerSlidingTabStrip) findViewById(R.id.tabs);
        // 为ViewPager实例加入自己定义的Adapter
        pager.setAdapter(new MyPagerAdapter(getSupportFragmentManager()));
        // 将ViewPager的实例设置到了PagerSlidingTabStrip中
        tabs.setViewPager(pager);
        // 对PagerSlidingTabStrip的细节进行配置
        setTabsValue();
    }

    /**
     * 对PagerSlidingTabStrip的各项属性进行赋值。

     */
    private void setTabsValue() {
        // 设置Tab是自己主动填充满屏幕的
        tabs.setShouldExpand(true);
        // 设置Tab的切割线是透明的
        tabs.setDividerColor(Color.TRANSPARENT);
        // 设置Tab底部线的高度
        tabs.setUnderlineHeight((int) TypedValue.applyDimension(
                TypedValue.COMPLEX_UNIT_DIP, 1, dm));
        // 设置Tab Indicator的高度
        tabs.setIndicatorHeight((int) TypedValue.applyDimension(
                TypedValue.COMPLEX_UNIT_DIP, 4, dm));
        // 设置Tab标题文字的大小
        tabs.setTextSize((int) TypedValue.applyDimension(
                TypedValue.COMPLEX_UNIT_SP, 16, dm));
        // 设置Tab Indicator的颜色
        tabs.setIndicatorColor(Color.parseColor("#45c01a"));
        // 设置选中Tab文字的颜色 (这是我自己定义的一个方法)
        tabs.setSelectedTextColor(Color.parseColor("#45c01a"));
        // 取消点击Tab时的背景色
        tabs.setTabBackground(0);
    }

    public class MyPagerAdapter extends FragmentPagerAdapter {

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

        private final String[] titles = { "游记", "专题", "目的地" };

        @Override
        public CharSequence getPageTitle(int position) {
            return titles[position];
        }

        @Override
        public int getCount() {
            return titles.length;
        }

        @Override
        public Fragment getItem(int position) {
            switch (position) {
                case 0:
                    if (travelsFragment == null) {
                        travelsFragment = new TravelsFragment();
                    }
                    return travelsFragment;
                case 1:
                    if (subjectFragment == null) {
                        subjectFragment = new SubjectFragment();
                    }
                    return subjectFragment;
                case 2:
                    if (destinationFragment == null) {
                        destinationFragment = new DestinationFragment();
                    }
                    return destinationFragment;
                default:
                    return null;
            }
        }

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        return false;
    }

    @Override
    public boolean onMenuOpened(int featureId, Menu menu) {
        if (featureId == Window.FEATURE_ACTION_BAR && menu != null) {
            if (menu.getClass().getSimpleName().equals("MenuBuilder")) {
                try {
                    Method m = menu.getClass().getDeclaredMethod(
                            "setOptionalIconsVisible", Boolean.TYPE);
                    m.setAccessible(true);
                    m.invoke(menu, true);
                } catch (Exception e) {
                }
            }
        }
        return super.onMenuOpened(featureId, menu);
    }

    private void setOverflowShowingAlways() {
        try {
            ViewConfiguration config = ViewConfiguration.get(this);
            Field menuKeyField = ViewConfiguration.class
                    .getDeclaredField("sHasPermanentMenuKey");
            menuKeyField.setAccessible(true);
            menuKeyField.setBoolean(config, false);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}

效果如图：

在游记的Fragment中，使用了不规则的瀑布流，关于瀑布流的使用请參考下一篇博文。