ViewPager实现图片切换

xml布局:

<RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="260dp">
        <android.support.v4.view.ViewPager
            android:id="@+id/view_pager"
            android:background="#000"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
        <LinearLayout
            android:id="@+id/layout_point"
            android:background="#00000000"
            android:gravity="center"
            android:layout_width="match_parent"
            android:layout_height="20dp"
            android:orientation="horizontal"
            android:layout_marginBottom="40dp"
            android:layout_alignParentBottom="true"/>
    </RelativeLayout>

activity代码:


import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.bumptech.glide.Glide;
import com.example.uoso.myapplicationdemo.R;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * ViewPager显示图片
 */
public class Fragment2 extends Fragment{

    private ViewPager viewPager;
    private LinearLayout layoutPoint;
    private String[] imgs = {"1图片url"
            ,"2图片url",
            "3图片url"};

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment2, null);
        viewPager = (ViewPager) view.findViewById(R.id.view_pager);
        layoutPoint = (LinearLayout) view.findViewById(R.id.layout_point);       
        initView();
        return view;
    }

    private void initView(){        
        //ViewPager相关
        ViewPagerAdater myAdater = new ViewPagerAdater(getContext());
        viewPager.setAdapter(myAdater);
        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageSelected(int position) {
                //在滑动完成后向布局中添加小圆点
                setLayoutPoint(position);
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
        setLayoutPoint(0);
    }

    /**
     * 设置小圆点布局
     * @param position
     */
    private void setLayoutPoint(int position){
        layoutPoint.removeAllViews();
        for (int i = 0; i <3 ; i++) {
            ImageView imageView = new ImageView(getContext());
            //设置ImageView
            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(20, 20);
            params.setMargins(10,0,10,0);
            imageView.setLayoutParams(params);
            //设置小圆点样式
            if (position==i){
                imageView.setImageDrawable(getResources().getDrawable(R.drawable.point_white));
            }else {
                imageView.setImageDrawable(getResources().getDrawable(R.drawable.point_gray));
            }
            layoutPoint.addView(imageView);
        }
    }  

    public class ViewPagerAdater extends PagerAdapter {
        private Context context;

        public ViewPagerAdater(Context context) {
            this.context = context;
        }

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

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            ImageView imageView = new ImageView(context);
            imageView.setScaleType(ImageView.ScaleType.FIT_XY);
            Glide.with(context).load(imgs[position]).into(imageView);
            container.addView(imageView);
            return imageView;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            container.removeView((ImageView) object);
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return view == object;
        }
    }


}

小圆点样式:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="#fddc04"/>
    <corners android:radius="5dp"/>
</shape>

Glide依赖:

compile 'com.github.bumptech.glide:glide:3.7.0'

猜你喜欢

转载自blog.csdn.net/an_nal/article/details/80324509