Android中ViewPage的使用

 

ViewPage的使用

package com.gfive.help;

import java.io.File;

import java.util.ArrayList;

import java.util.List;



import com.gfive.help.tools.Tools;



import android.app.Activity;

import android.content.Context;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.os.Bundle;

import android.os.Environment;

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.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.view.Window;

import android.view.ViewGroup.LayoutParams;

import android.widget.ImageView;

import android.widget.Toast;



public class ViewPageActivity extends Activity {

	ViewPager viewPager;

	ArrayList<View> list;

	ViewGroup main, group;

	ImageView imageView;

	ImageView[] imageViews;

	private static int c_id = 0;

	private static final String IMAGE_PATH = "/gfive/images";

	/**

	 * 图片类型

	 */

	public static final String IMAGE_TYPE = "image_type";

	

	private String imageType;

	@Override

	public void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		this.requestWindowFeature(Window.FEATURE_NO_TITLE);

		if(!Tools.existSDcard(this)){//如果没有内存卡，请绕开

				finish();

		}

		imageType = getIntent().getStringExtra(IMAGE_TYPE);		//获取图片类型

		LayoutInflater inflater = getLayoutInflater();

		List<Bitmap> lists = getBitmaps();

		list = new ArrayList<View>();

		ImageView iv = null;

		for(int i = 0;i<lists.size();i++){

			iv = new ImageView(this);

			iv.setImageBitmap(lists.get(i));

			list.add(iv);

		}

		imageViews = new ImageView[list.size()];

		ViewGroup main = (ViewGroup) inflater.inflate(R.layout.tutorials_layout, null);

		ViewGroup group = (ViewGroup) main.findViewById(R.id.viewGroup);

		viewPager = (ViewPager) main.findViewById(R.id.viewPager);

		for (int i = 0; i < list.size(); i++) {

			imageView = new ImageView(ViewPageActivity.this);

			imageView.setLayoutParams(new LayoutParams(12, 12));

			imageViews[i] = imageView;

			if (i == 0) {

				imageViews[i].setBackgroundResource(R.drawable.guide_dot_white);

			} else {

				imageViews[i].setBackgroundResource(R.drawable.guide_dot_black);

			}

			group.addView(imageView);

		}

		setContentView(main);

		viewPager.setAdapter(new MyAdapter());

		viewPager.setOnPageChangeListener(new MyListener());

		viewPager.setCurrentItem(300);

	}



	class MyAdapter extends PagerAdapter {

		@Override

		public int getCount() {

			return Integer.MAX_VALUE;

		}



		@Override

		public boolean isViewFromObject(View arg0, Object arg1) {

			return arg0 == arg1;

		}



		@Override

		public int getItemPosition(Object object) {

			return super.getItemPosition(object);

		}



		@Override

		public void destroyItem(View arg0, int arg1, Object arg2) {

		}



		@Override

		public Object instantiateItem(View arg0, int arg1) {

			try {

				((ViewPager) arg0).addView(list.get(arg1 % list.size()), 0);

			} catch (Exception e) {

			}

			return list.get(arg1 % list.size());

		}



		@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) {

		}

	}



	class MyListener implements OnPageChangeListener {

		// 当滑动状态改变时调用

		@Override

		public void onPageScrollStateChanged(int arg0) {



		}



		// 当当前页面被滑动时调用

		@Override

		public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

			if(position==list.size()-1){	//最后一页是关掉帮助

				finish();

			}

		}



		// 当新的页面被选中时调用

		@Override

		public void onPageSelected(int location) {

			if (location > 2 && list.size()>0) {

				location = location % list.size();

			}

			c_id = location;

			for (int i = 0; i < imageViews.length; i++) {

				imageViews[location].setBackgroundResource(R.drawable.guide_dot_white);

				if (location != i) {imageViews[i].setBackgroundResource(R.drawable.guide_dot_black);

				}

			}

		}

	}

	

	@Override

	protected void onDestroy() {

		finish();

		super.onDestroy();

		

	}

	

	/**

	 * 获取手机中的图片集合

	 * @return

	 */

	private List<Bitmap> getBitmaps(){

		int i = 1;

		List<Bitmap> bitmaps = new ArrayList<Bitmap>();

		StringBuilder sbPath = new StringBuilder();

		sbPath.append(Tools.SDCARD_STORAGE_PATH).append(IMAGE_PATH).append(imageType);

		while(true){

			File file = new File(sbPath.toString()+("guide_img"+i+".png").toString());

			if(!file.exists()) break;

			bitmaps.add(BitmapFactory.decodeFile(sbPath.toString()+("guide_img"+i+".png")));

			i++;

		}

		return bitmaps;

	}

}

　　布局文件：

<?xml version="1.0" encoding="utf-8"?> 

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" 

	android:layout_width="fill_parent" 

	android:layout_height="fill_parent" 

	android:orientation="vertical" > 

		<android.support.v4.view.ViewPager 

			android:id="@+id/viewPager" 

			android:layout_width="fill_parent" 

			android:layout_height="wrap_content" /> 

		<RelativeLayout 

			android:layout_width="fill_parent" 

			android:layout_height="wrap_content" 

			android:orientation="vertical" > 

					<LinearLayout 

					android:id="@+id/viewGroup" 

					android:layout_width="fill_parent" 

					android:layout_height="wrap_content" 

					android:layout_alignParentBottom="true" 

					android:layout_marginBottom="30dp" 

					android:gravity="center_horizontal" 

					android:orientation="horizontal" /> 

		</RelativeLayout> 

</FrameLayout>