ViewPagerIndicator簡要使用方法

ViewPager指針項目，在使用ViewPager的時候能夠指示ViewPager所在的位置，就像Google Play中切換的效果一樣，還能使用在應用初始化的介紹頁面

1. 引入ViewPagerIndicator庫

2. 編寫佈局文件

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

3. mIndicator.setViewPager(mViewPager);//將viewpager和mIndicator關聯起來,必須在viewpager設置完adapter後才能調用

//初始化ViewPagerIndicator
        indicator = (TabPageIndicator)view.findViewById(R.id.indicator);
        indicator.setViewPager(mViewPager);

1. 重寫PagerAdapter方法,返回頁面標題

        /**
         * 重寫此方法,返回頁面標題,用於viewpagerIndicator的頁籤顯示
         */
        @Override
        public CharSequence getPageTitle(int position) {
            return mNewsTabData.get(position).title;
        }

1. 自定義樣式修改
   在清單文件中我們需要更換的Activity下添加

android:theme="@style/Theme.PageIndicatorDefaults"

修改樣式就在PageIndicatorDefaults裏修改，包括字體大小，顏色，以及滑動的樣式都可以在此修改

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2011 Jake Wharton

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->

<resources>
    <style name="Theme.PageIndicatorDefaults" parent="android:Theme">
        <item name="vpiIconPageIndicatorStyle">@style/Widget.IconPageIndicator</item>
        <item name="vpiTabPageIndicatorStyle">@style/Widget.TabPageIndicator</item>
    </style>



    <style name="Widget">
    </style>

    <style name="Widget.TabPageIndicator" parent="Widget">
        <item name="android:gravity">center</item>
        <item name="android:background">@drawable/vpi__tab_indicator</item>
        <item name="android:paddingLeft">22dip</item>
        <item name="android:paddingRight">22dip</item>
        <item name="android:paddingTop">12dp</item>
        <item name="android:paddingBottom">12dp</item>
        <item name="android:textAppearance">@style/TextAppearance.TabPageIndicator</item>
        <item name="android:textSize">16sp</item>
        <item name="android:textColor">@drawable/slector_news_tab_color</item>
        <item name="android:maxLines">1</item>
    </style>

    <style name="TextAppearance.TabPageIndicator" parent="Widget">
        <item name="android:textStyle">bold</item>
        <item name="android:textColor">@color/vpi__dark_theme</item>
    </style>

    <style name="Widget.IconPageIndicator" parent="Widget">
        <item name="android:layout_marginLeft">6dp</item>
        <item name="android:layout_marginRight">6dp</item>
    </style>
</resources>