Android引導頁的實現

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實現原理：使用ViewPager控制項（com.android.support:support-v4:22.1.1），把引導頁的layout檔案放進ViewPager控制項就可以了。

ViewPager控制項本質上也是個清單控制項，橫向滾動，一個頁面一個頁面的滾動，底下並沒有捲軸，所以非常適合做引導頁，和頁簽的tap控制項來做橫向滾動的頁面也非常常用。

首先引用 com.android.support:support-v4:22.1.1

引導頁面的layout

 

<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:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    android:paddingBottom="@dimen/activity_vertical_margin"    tools:context="demo.viewpagerdemo.GuideActivity">    <android.support.v4.view.ViewPager        android:id="@+id/guide_activity_viewpager"        android:layout_width="fill_parent"        android:layout_height="fill_parent" >    </android.support.v4.view.ViewPager></RelativeLayout>

package demo.viewpagerdemo;import android.app.Activity;import android.support.v4.view.ViewPager;import android.os.Bundle;import android.view.LayoutInflater;import android.view.View;import java.util.ArrayList;import java.util.List;public class GuideActivity extends Activity {    private View mPage1, mPage2, mPage3;    private List<View> mViews = new ArrayList<View>();    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_guide);        ViewPager vp=(ViewPager)findViewById(R.id.guide_activity_viewpager);        mPage1 = LayoutInflater.from(this).inflate(                R.layout.guide_page1, null);        mPage2 = LayoutInflater.from(this).inflate(                R.layout.guide_page2, null);        mPage3 = LayoutInflater.from(this).inflate(                R.layout.guide_page3, null);        mViews.add(mPage1);        mViews.add(mPage2);        mViews.add(mPage3);        vp.setAdapter(new BasePagerAdapter(this, mViews));    }}

 注意ViewPager需要使用PagerAdapter適配器，所以需要繼承PagerAdapter類來實現一個適配器

public class BasePagerAdapter extends PagerAdapter {    private Context mContext;    private List<? extends View> mViews;    public BasePagerAdapter(Context mContext, List<? extends View> mViews) {        this.mContext = mContext;        this.mViews = mViews;    }    @Override    public int getCount() {        return mViews.size();    }    @Override    public boolean isViewFromObject(View view, Object object) {        return view == object;    }    @Override    public Object instantiateItem(ViewGroup container, int position) {        container.addView(mViews.get(position));        return mViews.get(position);    }    @Override    public void destroyItem(ViewGroup container, int position, Object object) {        container.removeView(mViews.get(position));    }}

 

Android引導頁的實現