Android ViewPager + Fragment实现滑动页面

摘要：效果类类通过静态方法获取实例，向传参数数据使用传递参数绑定控件设置圆角设置适配器监听页面改变页面选中设置缓存页数设置默认页添加三项数据

效果：

PagerData类：

 1 package com.cloud.viewpagerdemo;
 2 
 3 import java.io.Serializable;
 4 
 5 class PagerData implements Serializable {
 6 
 7     private int mImageResId;
 8     private String mContent;
 9 
10     PagerData(int imageResId, String content) {
11         mImageResId = imageResId;
12         mContent = content;
13     }
14 
15     public int getImageResId() {
16         return mImageResId;
17     }
18 
19     public void setImageResId(int imageResId) {
20         mImageResId = imageResId;
21     }
22 
23     public String getContent() {
24         return mContent;
25     }
26 
27     public void setContent(String content) {
28         mContent = content;
29     }
30 }

PagerFragment类：

 1 package com.cloud.viewpagerdemo;
 2 
 3 import android.graphics.Outline;
 4 import android.os.Bundle;
 5 import android.support.annotation.NonNull;
 6 import android.support.annotation.Nullable;
 7 import android.support.v4.app.Fragment;
 8 import android.view.LayoutInflater;
 9 import android.view.View;
10 import android.view.ViewGroup;
11 import android.view.ViewOutlineProvider;
12 import android.widget.ImageView;
13 import android.widget.TextView;
14 
15 public class PagerFragment extends Fragment {
16 
17     private static final String ARG_DATA = "data";
18 
19     private PagerData mData;
20 
21     private ImageView mImageView;
22     private TextView mContent;
23 
24     /**
25      * 通过静态方法获取Fragment实例，向Fragment传参数
26      * @param data 数据
27      * @return Fragment
28      */
29     public static PagerFragment newInstance(PagerData data) {
30         PagerFragment fragment = new PagerFragment();
31 
32         //使用FragmentArguments传递参数
33         Bundle args = new Bundle();
34         args.putSerializable(ARG_DATA, data);
35         fragment.setArguments(args);
36         return fragment;
37     }
38 
39     @Override
40     public void onCreate(@Nullable Bundle savedInstanceState) {
41         super.onCreate(savedInstanceState);
42         mData = (PagerData) getArguments().getSerializable(ARG_DATA);
43     }
44 
45     @Nullable
46     @Override
47     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
48                              @Nullable Bundle savedInstanceState) {
49         View view = inflater.inflate(R.layout.fragment_pager, container, false);
50 
51         //绑定控件
52         mImageView = view.findViewById(R.id.image_view);
53         mContent = view.findViewById(R.id.text_content);
54 
55         //ImageView设置圆角
56         ViewOutlineProvider viewOutlineProvider = new ViewOutlineProvider() {
57             @Override
58             public void getOutline(View view, Outline outline) {
59                 outline.setRoundRect(0, 0, mImageView.getWidth(), mImageView.getHeight(), 16);
60             }
61         };
62 
63         mImageView.setOutlineProvider(viewOutlineProvider);
64         mImageView.setClipToOutline(true);
65         mImageView.setImageResource(mData.getImageResId());
66         mContent.setText(mData.getContent());
67 
68         return view;
69     }
70 }

PagerActivity:

 1 package com.cloud.viewpagerdemo;
 2 
 3 import android.support.v4.app.Fragment;
 4 import android.support.v4.app.FragmentManager;
 5 import android.support.v4.app.FragmentStatePagerAdapter;
 6 import android.support.v4.view.ViewPager;
 7 import android.support.v7.app.AppCompatActivity;
 8 import android.os.Bundle;
 9 import android.widget.TextView;
10 
11 import java.util.ArrayList;
12 import java.util.List;
13 
14 public class PagerActivity extends AppCompatActivity {
15 
16     private List mPagerData = new ArrayList<>();
17 
18     private ViewPager mViewPager;
19     private TextView mTextPage;
20 
21     private String page = "1 / 3";
22 
23     @Override
24     protected void onCreate(Bundle savedInstanceState) {
25         super.onCreate(savedInstanceState);
26         setContentView(R.layout.activity_pager);
27 
28         initData();
29 
30         FragmentManager fragmentManager = getSupportFragmentManager();
31 
32         mViewPager = findViewById(R.id.view_pager);
33         mTextPage = findViewById(R.id.text_page);
34         //设置ViewPager适配器
35         mViewPager.setAdapter(new FragmentStatePagerAdapter(fragmentManager) {
36             @Override
37             public Fragment getItem(int position) {
38                 return PagerFragment.newInstance(mPagerData.get(position));
39             }
40 
41             @Override
42             public int getCount() {
43                 return mPagerData.size();
44             }
45         });
46 
47         //监听页面改变
48         mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
49             @Override
50             public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
51 
52             }
53 
54             @Override
55             public void onPageSelected(int position) {
56                 //页面选中
57                 page = String.valueOf(position + 1) + " / " + String.valueOf(mPagerData.size());
58                 mTextPage.setText(page);
59             }
60 
61             @Override
62             public void onPageScrollStateChanged(int state) {
63 
64             }
65         });
66         //设置缓存页数
67         mViewPager.setOffscreenPageLimit(3);
68         //设置默认页
69         mViewPager.setCurrentItem(0);
70 
71         mTextPage.setText(page);
72     }
73 
74     private void initData() {
75         //添加三项数据
76         mPagerData.add(new PagerData(R.drawable.img_0, "Photo by Adam Krowitz"));
77         mPagerData.add(new PagerData(R.drawable.img_1, "Photo by Samuel Ferrara"));
78         mPagerData.add(new PagerData(R.drawable.img_2, "Photo by Earth"));
79     }
80 }

fragment_pager：

 1 
 2 
 8 
 9     
23 
24         
32 
33         
42 
43     
44 
45 

activity_pager：

 1 
 2 
 9 
10     
19 
20         
27 
28     
29 
30     
38 
39     
40 
41     
50 
51