AndroidViewPager導航

發(fā)表時間：2020-10-19

發(fā)布人：葵宇科技

瀏覽次數(shù)：46

ViewPager做導航想不想有如許的效不雅：
比如說有四┞放圖片，下面有四個圓點，當頁面滑動的時刻一個點變年腋荷瑣點變?。ɑ蛘呤且粋€點變小一個點變大年夜），等于說同時在履行兩個動畫。
[img]http://img.blog.csdn.net/20150104151142094?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvU291bE9mQW5kcm9pZA==/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center

package com.example.day_2014_10_17_viewpager;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedHashMap;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.widget.ImageView;

import com.nineoldandroids.view.ViewHelper;
import com.panpass.adapter.MyViewPagerAdapter;
import com.panpass.view.MyViewPager;
import com.panpass.view.MyViewPager.DiyPageScrollListener;

public class MainActivity extends Activity {

	private Context mContext = this;
	private MyViewPager mViewPager;
	private ImageView imageView1, imageView2, imageView3, imageView4;
	private ArrayList<ImageView> mList;
	private HashMap<Integer, ImageView> mHashMap = new LinkedHashMap<Integer, ImageView>();
	private static final float SCALE_MAX = 0.55f;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		mList = new ArrayList<ImageView>();
		ImageView img = new ImageView(mContext);
		img.setBackgroundResource(R.drawable.guide_page1);
		mList.add(img);
		img = new ImageView(mContext);
		img.setBackgroundResource(R.drawable.guide_page2);
		mList.add(img);
		img = new ImageView(mContext);
		img.setBackgroundResource(R.drawable.guide_page3);
		mList.add(img);
		img = new ImageView(mContext);
		img.setBackgroundResource(R.drawable.guide_page4);
		mList.add(img);
		mViewPager = (MyViewPager) findViewById(R.id.view_pager);
		mViewPager.setAdapter(new MyViewPagerAdapter(mList));

		imageView1 = (ImageView) findViewById(R.id.imageView1);
		imageView2 = (ImageView) findViewById(R.id.imageView2);
		imageView3 = (ImageView) findViewById(R.id.imageView3);
		imageView4 = (ImageView) findViewById(R.id.imageView4);
		ViewHelper.setScaleX(imageView2, SCALE_MAX);
		ViewHelper.setScaleY(imageView2, SCALE_MAX);
		ViewHelper.setScaleX(imageView3, SCALE_MAX);
		ViewHelper.setScaleY(imageView3, SCALE_MAX);
		ViewHelper.setScaleX(imageView4, SCALE_MAX);
		ViewHelper.setScaleY(imageView4, SCALE_MAX);

		mHashMap.put(0, imageView1);
		mHashMap.put(1, imageView2);
		mHashMap.put(2, imageView3);
		mHashMap.put(3, imageView4);
		mViewPager.setDiyOnPageScrollListener(new DiyPageScrollListener() {

			@Override
			public void diyOnPageScrollListener(int position,
					float positionOffset, int positionOffsetPixels,
					boolean left, boolean right) {

				// 獲取左邊的View
				ImageView mLeftImg = mHashMap.get(position);
				// 獲取右邊的View
				ImageView mRightImg = mHashMap.get(position + 1);
				// 斷定滑動的偏向
				float mScaleRight;
				float mScaleLeft;
				/**
				 * 留意事宜： 1 留意你要很靈敏的斷定ViewPager的切換偏向是很難的，對于請求很高的應用來說是做不到了。 2
				 * 不管是向左滑動照樣向右滑動，他們有的都是同一種算法
				 */

				if (mRightImg != null) {
					/**
					 * 縮小比例 如不雅手指大年夜右到左的滑動（切換到后一個）：0.0~1.0，即大年夜一半到最大年夜
					 * 如不雅手指大年夜左到右的滑動（切換到前一個）：1.0~0，即大年夜最大年夜到一半
					 */
					mScaleRight = (1-SCALE_MAX) * positionOffset + SCALE_MAX;
					/**
					 * x偏移量： 如不雅手指大年夜右到左的滑動（切換到后一個）：0-720 如不雅手指大年夜左到右的滑動（切換到前一個）：720-0
					 */
					ViewHelper.setScaleX(mRightImg, mScaleRight);
					ViewHelper.setScaleY(mRightImg, mScaleRight);
				}
				if (mLeftImg != null) {

					mScaleLeft = (1-SCALE_MAX) * (1 - positionOffset) + SCALE_MAX;
					/**
					 * x偏移量： 如不雅手指大年夜右到左的滑動（切換到后一個）：0-720 如不雅手指大年夜左到右的滑動（切換到前一個）：720-0
					 */
					ViewHelper.setScaleX(mLeftImg, mScaleLeft);
					ViewHelper.setScaleY(mLeftImg, mScaleLeft);

				}

			}
		});

	}
}

package com.panpass.adapter;

import java.util.ArrayList;

import android.support.v4.view.PagerAdapter;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

public class MyViewPagerAdapter extends PagerAdapter {


	private ArrayList<ImageView> imgList;
	
	public MyViewPagerAdapter(ArrayList<ImageView> imgList) {
		super();
		this.imgList = imgList;
	}

	@Override
	public int getCount() {
		return imgList.size();
	}

	@Override
	public Object instantiateItem(ViewGroup container, int position) {
		
		ImageView img = imgList.get(position);
		container.addView(img);
		return img;
	}
	@Override
	public void destroyItem(ViewGroup container, int position, Object object) {
		
		container.removeView((ImageView)object);
		
	}
	@Override
	public boolean isViewFromObject(View arg0, Object arg1) {
		return arg0 == (View)arg1;
	}

}

package com.panpass.view;

import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;

public class MyViewPager extends ViewPager {

	private boolean left = false;  
	private boolean right = false;  
	private boolean isScrolling = false; 
	
	private int lastValue = http://www.sjsjw.com/100/000297MYM009910/-1;  
	private ChangeViewCallback changeViewCallback = null;  

	public MyViewPager(Context context, AttributeSet attrs) {  
		super(context, attrs);  
		init();  
	}  

	public MyViewPager(Context context) {  
		super(context);  
		init();  
	}  

	private DiyPageScrollListener listener1;

	public interface DiyPageScrollListener{

		void diyOnPageScrollListener(int position, float positionOffset,  
				int positionOffsetPixels,boolean left,boolean right);
	}

	public void setDiyOnPageScrollListener(DiyPageScrollListener listener){

		this.listener1 = listener;
	}
	@Override
	protected void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
		listener1.diyOnPageScrollListener(position, positionOffset, positionOffsetPixels,left,right);
		super.onPageScrolled(position, positionOffset, positionOffsetPixels);
	}

	/** 
	 * init method . 
	 */  
	private void init() {  
//		setOnPageChangeListener(listener);  
	}  

	/** 
	 * listener ,to get move direction . 
	 */  
	public  OnPageChangeListener listener = new OnPageChangeListener() {  
		@Override  
		public void onPageScrollStateChanged(int arg0) {  
			if (arg0 == 1) {  
				isScrolling = true;  
			} else {  
				isScrolling = false;  
			}  

			if (arg0 == 2) {  
			
				if(changeViewCallback!=null){  
					changeViewCallback.changeView(left, right);  
				}  
				right = left = false;  
			}  

		}  

		@Override  
		public void onPageScrolled(int arg0, float arg1, int arg2) {  
			if (isScrolling) {  
				if (lastValue > arg2) {  
					// 遞減，向右側(cè)滑動  
					right = true;  
					left = false;  
				} else if (lastValue < arg2) {  
					// 遞減，向右側(cè)滑動  
					right = false;  
					left = true;  
				} else if (lastValue == arg2) {  
					right = left = false;  
				}  
			}  
			lastValue = arg2;  
		}  

		@Override  
		public void onPageSelected(int arg0) {  
			if(changeViewCallback!=null){  
				changeViewCallback.getCurrentPageIndex(arg0);  
			}  
		}  
	};  

	/** 
	 * 獲得是否向右側(cè)滑動 
	 * @return true 為右滑動 
	 */  
	public boolean getMoveRight(){  
		return right;  
	}  

	/** 
	 * 獲得是否向左側(cè)滑動 
	 * @return true 為左做滑動 
	 */  
	public boolean getMoveLeft(){  
		return left;  
	}  

	/** 
	 *  滑動狀況改變回調(diào) 
	 * @author zxy 
	 * 
	 */  
	public interface ChangeViewCallback{  
		public  void changeView(boolean left,boolean right);  
		public  void  getCurrentPageIndex(int index);  
	}  

	public void  setChangeViewCallback(ChangeViewCallback callback){  
		changeViewCallback = callback;  
	}  


}

<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" >

    <com.panpass.view.MyViewPager
        android:id="@+id/view_pager"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="50dp"
        android:gravity="center" >

        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src=http://www.sjsjw.com/100/000297MYM009910/"@drawable/banner_circle_big" />