ViewPager实现引导界面以及进入下一个activity解决办法

这次项目中实现了用户引导滑动图片，到最后一张图片的时候，我认为理想的是同时具备以下两点：

1）用户可以点击上面的“开始使用”这样的按钮可以进入主界面；

2）用户接着滑动下一个图片的手势而进入主界面；

3）用户在引导界面点击返回键的时候直接进入主界面；

增加“开始使用”按钮方式：

可以定义一个layout的xml再加载：一个LinearLayout，里面一个button。默认button是“gone”，

xml如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/guide_item"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="5" />

    <Button
        android:id="@+id/start"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/guide_start"
        android:visibility="gone" >
    </Button>

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1" />

</LinearLayout>

button上下增加了textview，我是为了控制button在整个界面的位置。

引导的图片是其背景即可。

实现如下：

guide_activity.xml

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

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

</LinearLayout>

GuideActivity.java：

/**
 * 引导界面
 * @author maria
 * 2012-07-19
 */
package com.maria.test;

import java.util.ArrayList;
import java.util.List;
import com.trunkbow.talker.R;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.DisplayMetrics;
import android.view.GestureDetector;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.LinearLayout;

public class GuideActivity extends Activity {
    private ViewPager viewPager;
    private List<View> mImageViews; // 滑动的图片集合
    private int[] imageResId; // 图片ID
    private int currentItem = 0; // 当前图片的索引号
    private GestureDetector gestureDetector; // 用户滑动
    /** 记录当前分页ID */
    private int flaggingWidth;// 互动翻页所需滚动的长度是当前屏幕宽度的1/3

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.guide_activity);
        gestureDetector = new GestureDetector(new GuideViewTouch());

        // 获取分辨率
        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        flaggingWidth = dm.widthPixels / 3;

        imageResId = new int[] { R.drawable.guide_1, R.drawable.guide_2 };

        mImageViews = new ArrayList<View>();

        // 初始化图片资源
        LayoutInflater viewInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        // 0
        View convertView0 = viewInflater.inflate(R.layout.guide_item, null);
        LinearLayout linearLayout0 = (LinearLayout) convertView0
                .findViewById(R.id.guide_item);
        linearLayout0.setBackgroundResource(imageResId[0]);
        mImageViews.add(linearLayout0);
        // 1
        View convertView1 = viewInflater.inflate(R.layout.guide_item, null);
        LinearLayout linearLayout1 = (LinearLayout) convertView1
                .findViewById(R.id.guide_item);
        linearLayout1.setBackgroundResource(imageResId[1]);
        Button btn = (Button) convertView1.findViewById(R.id.start);
        btn.setVisibility(View.VISIBLE);
        btn.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                GoToMainActivity();
            }
        });
        mImageViews.add(linearLayout1);

        viewPager = (ViewPager) findViewById(R.id.guide_view);
        viewPager.setAdapter(new MyAdapter());// 设置填充ViewPager页面的适配器
        // 设置一个监听器，当ViewPager中的页面改变时调用
        viewPager.setOnPageChangeListener(new MyPageChangeListener());
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent event) {
        if (gestureDetector.onTouchEvent(event)) {
            event.setAction(MotionEvent.ACTION_CANCEL);
        }
        return super.dispatchTouchEvent(event);
    }

    private class GuideViewTouch extends SimpleOnGestureListener {
        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
                float velocityY) {
            if (currentItem == 1) {
                if (Math.abs(e1.getX() - e2.getX()) > Math.abs(e1.getY()
                        - e2.getY())
                        && (e1.getX() - e2.getX() <= (-flaggingWidth) || e1
                                .getX() - e2.getX() >= flaggingWidth)) {
                    if (e1.getX() - e2.getX() >= flaggingWidth) {
                        GoToMainActivity();
                        return true;
                    }
                }
            }
            return false;
        }
    }

    /**
     * 进入主界面
     */
    void GoToMainActivity() {
        Intent i = new Intent(GuideActivity.this, MainActivivty.class);
        startActivity(i);
        finish();
    }

    /**
     * 当ViewPager中页面的状态发生改变时调用
     *
     * @author Administrator
     *
     */
    private class MyPageChangeListener implements OnPageChangeListener {

        /**
         * This method will be invoked when a new page becomes selected.
         * position: Position index of the new selected page.
         */
        public void onPageSelected(int position) {
            currentItem = position;
        }

        public void onPageScrollStateChanged(int arg0) {
        }

        public void onPageScrolled(int arg0, float arg1, int arg2) {
        }
    }

    /**
     * 填充ViewPager页面的适配器
     *
     * @author Administrator
     *
     */
    private class MyAdapter extends PagerAdapter {

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

        @Override
        public Object instantiateItem(View arg0, int arg1) {
            ((ViewPager) arg0).addView(mImageViews.get(arg1));
            return mImageViews.get(arg1);
        }

        @Override
        public void destroyItem(View arg0, int arg1, Object arg2) {
            ((ViewPager) arg0).removeView((View) arg2);
        }

        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
            return arg0 == arg1;
        }

        @Override
        public void restoreState(Parcelable arg0, ClassLoader arg1) {

        }

        @Override
        public Parcelable saveState() {
            return null;
        }

        @Override
        public void startUpdate(View arg0) {

        }

        @Override
        public void finishUpdate(View arg0) {

        }
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // TODO Auto-generated method stub
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            GoToMainActivity();
            return false;
        }
        return super.onKeyDown(keyCode, event);
    }

}