当fragment中的viewpager滑动到第一个，继续像后滑动，就滑动到第一个fragment 滑动到最后一个继续向前滑动，就去第三个fragment
上代码MainActivity
package com.example.shijianlianxi;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends FragmentActivity {
ViewPager viewpager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewpager = findViewById(R.id.viewpager);
viewpager.setAdapter(new FragmentPagerAdapter(getSupportFragmentManager()) {
@Override
public Fragment getItem(int i) {
switch(i){
case 0:
return new AFragment();
case 1:
return new BFragment();
case 2:
return new CFragment();
}
return null;
}
@Override
public int getCount() {
return 3;
}
});
viewpager.setCurrentItem(1);
}
}
## adapter
package com.example.shijianlianxi;
import android.content.Context; import android.support.annotation.NonNull; import android.support.v4.view.PagerAdapter; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView;
import java.util.ArrayList; import java.util.List;
public class MAdapter extends PagerAdapter {
Context context;
List<Integer> list;
public MAdapter(Context context) {
this.context = context;
list = new ArrayList<>();
}
public void setdata(List<Integer> list){
this.list.clear();
this.list.addAll(list);
notifyDataSetChanged();
}
@Override
public int getCount() {
return Integer.MAX_VALUE;
}
@Override
public boolean isViewFromObject(@NonNull View view, @NonNull Object o) {
return view==o;
}
@NonNull
@Override
public Object instantiateItem(@NonNull ViewGroup container, int position) {
ImageView imageView = new ImageView(context);
imageView.setImageResource(list.get(position % list.size()));
container.addView(imageView);
return imageView;
}
@Override
public void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {
container.removeView((View) object);
}
}
Fragment中的viewpager自动轮播
package com.example.shijianlianxi;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.app.Fragment;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import java.util.ArrayList;
import java.util.List;
public class BFragment extends Fragment {
ViewPager viewpager;
List<Integer> list;
MAdapter adapter;
Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
int x = viewpager.getCurrentItem();
x++;
viewpager.setCurrentItem(x);
send();
}
};
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_b, container, false);
viewpager = view.findViewById(R.id.viewpager);
list = new ArrayList<>();
list.add(R.drawable.a);
list.add(R.drawable.b);
list.add(R.drawable.c);
list.add(R.drawable.d);
list.add(R.drawable.e);
adapter = new MAdapter(getActivity());
adapter.setdata(list);
viewpager.setAdapter(adapter);
viewpager.setCurrentItem(Integer.MAX_VALUE/2-3);
send();
viewpager.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
switch(motionEvent.getAction()){
case MotionEvent.ACTION_DOWN:
handler.removeMessages(1);
break;
case MotionEvent.ACTION_MOVE:
handler.removeMessages(1);
break;
case MotionEvent.ACTION_UP:
send();
break;
}
return false;
}
});
return view;
}
@Override
public void onPause() {
super.onPause();
handler.removeMessages(1);
}
@Override
public void onResume() {
super.onResume();
send();
}
public void send(){
if (adapter != null && adapter.getCount()>0){
handler.removeMessages(1);
handler.sendEmptyMessageDelayed(1,1000);
}
}
@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if(isVisibleToUser) {
send();
} else {
handler.removeMessages(1);
}
}
}
布局文件
<?xml version="1.0" encoding="utf-8"?>
<com.example.shijianlianxi.AAAAAFragment 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"
android:background="@color/yellow"
tools:context=".BFragment">
<com.example.shijianlianxi.AAViewPager
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="180dp" />
</com.example.shijianlianxi.AAAAAFragment>
事件分发的主要。步骤
package com.example.shijianlianxi;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.FrameLayout;
public class AAAAAFragment extends FrameLayout {
public AAAAAFragment( Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
Log.e("zhx","老师开始发消息");
return super.dispatchTouchEvent(ev);
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
Log.e("zhx","没有人执行");
return super.onTouchEvent(ev);
}
}
package com.example.shijianlianxi;
import android.content.Context;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
public class AAViewPager extends ViewPager {
int x = 0;
int x1 = 0;
public AAViewPager(@NonNull Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
Log.e("zhx","班长接受消息");
return super.dispatchTouchEvent(ev);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
int currentItem = this.getCurrentItem();
if (currentItem % 5 == 0){
boolean s = set(event,currentItem);
return s;
}else if (currentItem % 5 == 4){
boolean s = set(event,currentItem);
return s;
}else{
boolean s = set(event,currentItem);
return s;
}
}
public boolean set(MotionEvent event,int currentItem){
int action = event.getAction();
if (action == MotionEvent.ACTION_DOWN){
x = (int)event.getX();
}
if (action == MotionEvent.ACTION_MOVE){
x1 = (int)event.getX();
}
if (currentItem % 5 == 0 && x1-x>0){
Log.e("zhx","班长bu拦截消息");
return false;
}
if (currentItem % 5 == 4 && x1-x<0){
Log.e("zhx","班长bu拦截消息");
return false;
}
return super.onTouchEvent(event);
}
}
