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Android ViewPager实现每隔两秒自动切换图片功能

作者:My_苦行僧

图片来回自动切换,设计非常人性化,那么图片自动切换功能基于代码如何实现的呢?下面小编给大家带来了Android ViewPager实现每隔两秒自动切换图片功能,感兴趣的朋友一起看看吧

布局代码:

<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" >

    <FrameLayout
        android:layout_width="fill_parent"
        android:layout_height="200dip"
        >

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

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="35dip"
            android:orientation="vertical"
            android:layout_gravity="bottom"
            android:gravity="center"
            android:background="#33000000"
            >

            <TextView
                android:id="@+id/title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="图片标题"
                android:textColor="@android:color/white"
                />

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:orientation="horizontal"
                android:layout_marginTop="3dip"
                >

                <View
                    android:id="@+id/dot_0"
                    android:layout_width="5dip"
                    android:layout_height="5dip"
                    android:layout_marginLeft="2dip"
                    android:layout_marginRight="2dip"
                    android:background="@drawable/dot_focused"
                    />
                <View
                    android:id="@+id/dot_1"
                    android:layout_width="5dip"
                    android:layout_height="5dip"
                    android:layout_marginLeft="2dip"
                    android:layout_marginRight="2dip"
                    android:background="@drawable/dot_normal"
                    />
                <View
                    android:id="@+id/dot_2"
                    android:layout_width="5dip"
                    android:layout_height="5dip"
                    android:layout_marginLeft="2dip"
                    android:layout_marginRight="2dip"
                    android:background="@drawable/dot_normal"
                    />
                <View
                    android:id="@+id/dot_3"
                    android:layout_width="5dip"
                    android:layout_height="5dip"
                    android:layout_marginLeft="2dip"
                    android:layout_marginRight="2dip"
                    android:background="@drawable/dot_normal"
                    />
                <View
                    android:id="@+id/dot_4"
                    android:layout_width="5dip"
                    android:layout_height="5dip"
                    android:layout_marginLeft="2dip"
                    android:layout_marginRight="2dip"
                    android:background="@drawable/dot_normal"
                    />

            </LinearLayout>


        </LinearLayout>

    </FrameLayout>


</RelativeLayout>

正常的shape图形dot_normal.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval"
    >

    <corners android:radius="5dip" />

    <solid android:color="#55000000" />

</shape>

获取焦点的shape图形 dot_focused.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval"
    >

    <corners android:radius="5dip" />

    <solid android:color="#aaFFFFFF" />

</shape>

具体实现代码:

import java.util.ArrayList;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends Activity {

    private int imageIds[];
    private String[] titles;
    private ArrayList<ImageView> images;
    private ArrayList<View> dots;
    private TextView title;
    private ViewPager mViewPager;
    private ViewPagerAdapter adapter;

    private int oldPosition = 0;//记录上一次点的位置
    private int currentItem; //当前页面
    private ScheduledExecutorService scheduledExecutorService;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //图片ID
        imageIds = new int[]{
            R.drawable.a,
            R.drawable.b,
            R.drawable.c,
            R.drawable.d,
            R.drawable.e
        };

        //图片标题
        titles = new String[]{
            "巩俐不低俗,我就不能低俗",
            "扑树又回来啦!再唱经典老歌引万人大合唱",
            "揭秘北京电影如何升级",
            "乐视网TV版大派送",
            "热血的反杀"
        };

        //显示的图片
        images = new ArrayList<ImageView>();
        for(int i =0; i < imageIds.length; i++){
            ImageView imageView = new ImageView(this);
            imageView.setBackgroundResource(imageIds[i]);

            images.add(imageView);
        }

        //显示的点
        dots = new ArrayList<View>();
        dots.add(findViewById(R.id.dot_0));
        dots.add(findViewById(R.id.dot_1));
        dots.add(findViewById(R.id.dot_2));
        dots.add(findViewById(R.id.dot_3));
        dots.add(findViewById(R.id.dot_4));

        title = (TextView) findViewById(R.id.title);
        title.setText(titles[0]);

        mViewPager = (ViewPager) findViewById(R.id.vp);

        adapter = new ViewPagerAdapter();
        mViewPager.setAdapter(adapter);

        mViewPager.setOnPageChangeListener(new OnPageChangeListener() {



            @Override
            public void onPageSelected(int position) {
                // TODO Auto-generated method stub
                title.setText(titles[position]);

                dots.get(oldPosition).setBackgroundResource(R.drawable.dot_normal);
                dots.get(position).setBackgroundResource(R.drawable.dot_focused);

                oldPosition = position;
                currentItem = position;
            }

            @Override
            public void onPageScrolled(int arg0, float arg1, int arg2) {
                // TODO Auto-generated method stub

            }

            @Override
            public void onPageScrollStateChanged(int arg0) {
                // TODO Auto-generated method stub

            }
        });

    }

    private class ViewPagerAdapter extends PagerAdapter {

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return images.size();
        }

        //是否是同一张图片
        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
            // TODO Auto-generated method stub
            return arg0 == arg1;
        }

        @Override
        public void destroyItem(ViewGroup view, int position, Object object) {
            // TODO Auto-generated method stub
//            super.destroyItem(container, position, object);
//            view.removeViewAt(position);
            view.removeView(images.get(position));

        }

        @Override
        public Object instantiateItem(ViewGroup view, int position) {
            // TODO Auto-generated method stub
            view.addView(images.get(position));

            return images.get(position);
        }
    }

    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();

        scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();

        //每隔2秒钟切换一张图片
        scheduledExecutorService.scheduleWithFixedDelay(new ViewPagerTask(), 2, 2, TimeUnit.SECONDS);
    }

    //切换图片
    private class ViewPagerTask implements Runnable {

        @Override
        public void run() {
            // TODO Auto-generated method stub
            currentItem = (currentItem +1) % imageIds.length;
            //更新界面
//            handler.sendEmptyMessage(0);
            handler.obtainMessage().sendToTarget();
        }

    }

    private Handler handler = new Handler(){

        @Override
        public void handleMessage(Message msg) {
            // TODO Auto-generated method stub
            //设置当前页面
            mViewPager.setCurrentItem(currentItem);
        }

    };

    @Override
    protected void onStop() {
        // TODO Auto-generated method stub
        super.onStop();
    }

}

到此这篇关于Android ViewPager实现每隔两秒自动切换图片的文章就介绍到这了,更多相关ViewPager自动切换图片内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家!

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