android - 如何制作 viewpager 循环？

Question

我希望我的 ViewPager 实现在 View 之间循环，而不是在最后一个 View 处停止。例如，如果我有 3 个 View 要通过 ViewPager 显示，它应该在第三个 View 之后返回到第一个 View ，而不是在第三个 View 处停止。当用户在最后一页上向前滑动时，我希望它返回到第一页/ View

循环示例；

A,B,C,D <--- A,B,C,D ---> A,B,C,D

非常感谢，

Mypageradapter;

package com.example.pictures;

import android.content.Context;
import android.media.AudioManager;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;


public class MyPagerAdapter extends  PagerAdapter{

public int getCount() {
    return 6;
}

public Object instantiateItem(View collection, int position) {

    View view=null;

    LayoutInflater inflater = (LayoutInflater) collection.getContext()
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    int resId = 0;
    switch (position) {
    case 0:
        resId = R.layout.picture1;
        view = inflater.inflate(resId, null);         
        break;
    case 1:
        resId = R.layout.picture2;   
        view = inflater.inflate(resId, null);
        break;
    case 2:
        resId = R.layout.picture3;
        view = inflater.inflate(resId, null);
        break;
    case 3:
        resId = R.layout.picture4;
        view = inflater.inflate(resId, null);
        break;
    case 4:
        resId = R.layout.picture5;
        view = inflater.inflate(resId, null);   
        break;
    case 5:
        resId = R.layout.picture6;
        view = inflater.inflate(resId, null);
        break;
    }

    ((ViewPager) collection).addView(view, 0);

    return view;
}

@SuppressWarnings("unused")
private Context getApplicationContext() {
    // TODO Auto-generated method stub
    return null;
}


private void setVolumeControlStream(int streamMusic) {
    // TODO Auto-generated method stub

}


@SuppressWarnings("unused")
private Context getBaseContext() {
    // TODO Auto-generated method stub
    return null;
}


@SuppressWarnings("unused")
private PagerAdapter findViewById(int myfivepanelpager) {
    // TODO Auto-generated method stub
    return null;
}

@Override
public void destroyItem(View arg0, int arg1, Object arg2) {
    ((ViewPager) arg0).removeView((View) arg2);
}

@Override
public boolean isViewFromObject(View arg0, Object arg1) {
    return arg0 == ((View) arg1);

}

@Override
public Parcelable saveState() {
    return null;
}

public static Integer getItem(int position) {
    // TODO Auto-generated method stub
    return null;
}

}

OnPageChangeListener;

package com.example.pictures;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;


public class Pictures extends Activity implements OnPageChangeListener{
SoundManager snd; 
int sound1,sound2,sound3;
View view=null;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.picturespage);

 MyPagerAdapter adapter = new MyPagerAdapter();
 ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
 myPager.setAdapter(adapter);
 myPager.setCurrentItem(0); 
 myPager.setOnPageChangeListener(this);
snd = new SoundManager(this);
 sound1 = snd.load(R.raw.sound1);
 sound2 = snd.load(R.raw.sound2);
 sound3 = snd.load(R.raw.sound3);

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

}

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

}

public void onPageSelected(int position) {
    // TODO Auto-generated method stub

    switch (position) {
    case 0:
            snd.play(sound1);
        break;
    case 1:
        snd.play(sound2);
        break;
    case 2:
            snd.play(sound3);
        break;
    case 3:
      Toast.makeText(this, "1", Toast.LENGTH_SHORT).show();
        break;
    case 4:
       Toast.makeText(this, "2", Toast.LENGTH_SHORT).show();
        break;
    case 5:
        Toast.makeText(this, "3", Toast.LENGTH_SHORT).show();
        break;
    }
}
};

Answer 1

你需要创建一个如图所示的圆形适配器，然后将该适配器用作:

class MyGestureDetector extends SimpleOnGestureListener {
        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            try {
                if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH)
                    return false;
                // right to left swipe
                if(e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
                    Toast.makeText(SelectFilterActivity.this, "Left Swipe", Toast.LENGTH_SHORT).show();
                }  else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
                    Toast.makeText(SelectFilterActivity.this, "Right Swipe", Toast.LENGTH_SHORT).show();
                }
            } catch (Exception e) {
                // nothing
            }
            return false;
        }

    }

以上代码是从这里复制的Fling gesture detection on grid layout

另请参阅以下答案:

Implementing Circular Scrolling In PagerAdapter