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实现ViewPager实现类似微信的页面切换,此文通过Fragment适配器实现
首先在布局文件activity_main.xml添加ViewPager
ViewPager是页面,PagerTabStrip和 PagerTitleStrip是设置标题的
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<? xml version = "1.0" encoding = "utf-8" ?> < RelativeLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:layout_width = "match_parent" android:layout_height = "match_parent" > <!--页卡--> < android.support.v4.view.ViewPager android:id = "@+id/view1" android:layout_width = "wrap_content" android:layout_height = "wrap_content" > <!--页卡标题--> <!--PagerTitleStrip和PagerTabStrip功能差不多一致,使用了PagerTitleStrip那PagerTabStrip会失效--> < android.support.v4.view.PagerTabStrip android:id = "@+id/pagerTabStrip" android:layout_width = "wrap_content" android:layout_height = "wrap_content" /> </ android.support.v4.view.ViewPager > </ RelativeLayout > |
接下里创建3个布局文件,给ViewPager的适配器引用
view1.xml
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<? xml version = "1.0" encoding = "utf-8" ?> < LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:layout_width = "match_parent" android:layout_height = "match_parent" > < ImageView android:id = "@+id/img1" android:layout_height = "wrap_content" android:layout_width = "wrap_content" android:background = "@drawable/img1" android:layout_marginLeft = "30dp" /> </ LinearLayout > |
view2.xml
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<? xml version = "1.0" encoding = "utf-8" ?> < LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:layout_width = "match_parent" android:layout_height = "match_parent" > < ImageView android:id = "@+id/img2" android:layout_height = "match_parent" android:layout_width = "match_parent" android:background = "@drawable/img2" /> </ LinearLayout > |
view3.xml
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<? xml version = "1.0" encoding = "utf-8" ?> < LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:layout_width = "match_parent" android:layout_height = "match_parent" > < ImageView android:id = "@+id/img3" android:layout_height = "match_parent" android:layout_width = "match_parent" android:background = "@drawable/img3" /> </ LinearLayout > |
创建3个类继承Fragment,通过Fragment实现onCreateView方法把view.xml布局转换成View
MyFragment1.java
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package com.rui.viewpagerdemo; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; /** * Created by qqazl001 on 2018/3/26. */ public class MyFragment1 extends Fragment{ @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { //布局文件转成View //参数1:Fragment需要加载的布局文件 //参数2:加载layout的父ViewGroup //参数1:是否返回父ViewGroup对象,false为不 View view = inflater.inflate(R.layout.view1,container, false ); return view; } } |
MyFragment2.java
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package com.rui.viewpagerdemo; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; /** * Created by qqazl001 on 2018/3/26. */ public class MyFragment2 extends Fragment{ @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { //布局文件转成View //参数1:Fragment需要加载的布局文件 //参数2:加载layout的父ViewGroup //参数1:是否返回父ViewGroup对象,false为不 View view = inflater.inflate(R.layout.view2,container, false ); return view; } } |
MyFragment3.java
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package com.rui.viewpagerdemo; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; /** * Created by qqazl001 on 2018/3/26. */ public class MyFragment3 extends Fragment{ @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { //布局文件转成View //参数1:Fragment需要加载的布局文件 //参数2:加载layout的父ViewGroup //参数1:是否返回父ViewGroup对象,false为不 View view = inflater.inflate(R.layout.view3,container, false ); return view; } } |
创建适配器,新建类(MyAdapter),继承FragmentPagerAdapter
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package com.rui.viewpagerdemo; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentPagerAdapter; import android.support.v4.view.PagerAdapter; import android.view.View; import android.view.ViewGroup; import java.util.ArrayList; import java.util.List; /** * Created by qqazl001 on 2018/3/26. */ public class MyAdapter extends FragmentPagerAdapter{ List<Fragment> listFragment; List<String> listTab = new ArrayList<String>(); public MyAdapter(FragmentManager fm,List<Fragment> listFragment,List<String>listTab) { super (fm); this .listFragment=listFragment; this .listTab=listTab; } @Override public CharSequence getPageTitle( int position) { //返回标题名称 return listTab.get(position); } @Override public Fragment getItem( int position) { //返回页面内容 return listFragment.get(position); } @Override public int getCount() { //一共多少个页面 return listFragment.size(); } } |
在Activity实例化组件和适配器并添加监听,添加各种数据源等
监听实现接口OnPageChangeListener
ViewPager,添加监听方法 setOnPageChangeListener() 方法已经被 AS 移除了,建议使用 addOnPageChangeListener() 方法。
MainActivity.java
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package com.rui.viewpagerdemo; import android.annotation.SuppressLint; import android.graphics.Color; import android.support.v4.app.Fragment; import android.support.v4.view.PagerTabStrip; import android.support.v4.view.ViewPager; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Toast; import java.util.ArrayList; import java.util.List; //调用接口监听,并实现方法 public class MainActivity extends AppCompatActivity implements ViewPager.OnPageChangeListener{ private List<Fragment> listFragment; //声明List,存放Fagment private ViewPager viewPager; //声明ViewPager private PagerTabStrip pagerTabStrip; //声明PagerTabStrip private List<String> listTab; //声明List,存放标题 @SuppressLint ( "ResourceType" ) @Override protected void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); setContentView(R.layout.activity_main); //实例化List listFragment = new ArrayList<Fragment>(); //view加入list listFragment.add( new MyFragment1()); listFragment.add( new MyFragment2()); listFragment.add( new MyFragment3()); //标题加入list listTab = new ArrayList<String>(); listTab.add( "第一页" ); listTab.add( "第二页" ); listTab.add( "第三页" ); //为PagerTabStrip设置属性 pagerTabStrip = (PagerTabStrip)findViewById(R.id.pagerTabStrip); //pagerTabStrip.setBackgroundColor(color.white); 设置背景色 pagerTabStrip.setTextColor(Color.RED); //设置标题文字颜色 pagerTabStrip.setDrawFullUnderline( false ); //是否显示一条横线 pagerTabStrip.setTabIndicatorColor(Color.GREEN); //标题下的短粗线颜色 //实例化适配器 MyAdapter myAdapter = new MyAdapter(getSupportFragmentManager(),listFragment,listTab); //实例化ViewPager viewPager = (ViewPager) findViewById(R.id.view1); //为viewPager加载适配器 viewPager.setAdapter(myAdapter); //加载监听事件 viewPager.addOnPageChangeListener( this ); } @Override public void onPageScrolled( int position, float positionOffset, int positionOffsetPixels) { // position-点击滑动的界面的位置 // positionOffset-点击页面占整个屏幕的百分比 // positionOffsetPixels-屏幕像素的位置 } @Override public void onPageSelected( int position) { //滑动到第几页 Toast.makeText(MainActivity. this , "第" +(position+ 1 )+ "页" ,Toast.LENGTH_SHORT).show(); } @Override public void onPageScrollStateChanged( int state) { //state:滑动状态 //当页面停止的时候该参数为0,页面开始滑动的时候变成了1, //当手指从屏幕上抬起变为了2(无论页面是否从1跳到了2),当页面静止后又变成了0 //只在0,1,2三个数字之间切换. } } |
PS:以上很多都使用了 android.support.v4.* 这个包下的类,是为了向下兼容
ViewPager有三个适配器,适配不同的数据源。
1、继承自PagerAdapter的适配器适配List<View>的数据
2、继承自FragmentAdapter的适配器适配List<Fragment>的数据
3、继承自FragmentStateAdapter的适配器适配List<Fragment>的数据
其中后两种的区别是:2没有创建和销毁的过程,3有
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。
原文链接:https://blog.csdn.net/qqazl001/article/details/79701287