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);
	}

}