ViewPager滑动上一个声音

Question

在这里，我使用viewpager滑动我的图像，并且每次滑动图像时播放的声音都不相同。 现在它可以正常工作，但是当我向后滑动时声音与图像不匹配...

我的代码：-

imagepageradapter

package com.android.learning_numbers;

public class ImagePagerAdapter {

}

主要活动

package com.android.learning_numbers;

import android.media.MediaPlayer;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

public class Numbers extends Activity {

    MediaPlayer mp;
    MediaPlayer player;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_numbers);
        ViewPager viewPager = (ViewPager)findViewById(R.id.view_pager);
        ImagePagerAdapter adapter = new ImagePagerAdapter();
        viewPager.setAdapter(adapter);
        player = MediaPlayer.create(this, R.raw.jingle);
        player.setLooping(true);
        player.setVolume(100, 100);
        player.start();
     }

     @Override
     protected void onPause() {
         super.onPause();
         player.pause();
     }

     @Override
     protected void onResume() {
         super.onResume();
         player.start();
     }

private class ImagePagerAdapter extends PagerAdapter {

         private int[] mImages = new int[] {R.drawable.no1,R.drawable.no2,R.drawable.no3,R.drawable.no4,R.drawable.no5,R.drawable.no6,R.drawable.no7,R.drawable.no8,R.drawable.no9,R.drawable.no10,R.drawable.bg2,};
         private int[] mAudio = new int[]{R.raw.one,R.raw.two,R.raw.three,R.raw.four,R.raw.five,R.raw.six,R.raw.seven,R.raw.eight,R.raw.nine,R.raw.ten,R.raw.one,};

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

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

         @Override
         public Object instantiateItem(ViewGroup container, int position) {
            Context context = Numbers.this;
            ImageView imageView = new ImageView(context);
            int padding =context.getResources().  
            getDimensionPixelSize(R.dimen.activity_vertical_margin);
            imageView.setPadding(padding, padding, padding, padding);
            imageView.setScaleType(ImageView.ScaleType.CENTER);
            imageView.setImageResource(mImages[position]);
            ((ViewPager) container).addView(imageView, 0); 
            if(position>=1){
            mp = MediaPlayer.create(Numbers.this, mAudio[position-1]);
            mp.start();
            }
            return imageView;
         }

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

Answer 1

移动你MediaPlayer对象和代码播放声音onPageChangeListener您的ViewPager对象。 当前，它仅在实例化项目时才播放音频。

如果将它们移到onPageChangeListener ，它将在每次页面更改时播放，而不管是否实例化新项目。

@Override
protected void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_numbers);
    ViewPager viewPager = (ViewPager)findViewById(R.id.view_pager);
    ImagePagerAdapter adapter = new ImagePagerAdapter();
    viewPager.setAdapter(adapter);
    viewPager.setOnPageChangeListener(player);
    player = MediaPlayer.create(this, R.raw.jingle);
    player.setLooping(true);
    player.setVolume(100, 100);
    player.start();
 }

OnPageChangeListener player = new OnPageChangeListener()
{

    @Override
    public void onPageSelected(int arg0)
    {
        mp = MediaPlayer.create(Numbers.this, mAudio[arg0]);
        mp.start();
    }

    @Override
    public void onPageScrolled(int arg0, float arg1, int arg2)
    {
    }

    @Override
    public void onPageScrollStateChanged(int arg0)
    {
    }
};

Answer 2

我找到了答案。 现在这是绝对有效的代码

public class Numbers extends Activity {
    MediaPlayer mp;
    MediaPlayer BG;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_numbers);
        ViewPagerAdapter adapter = new ViewPagerAdapter(this, imageArra);
        ViewPager myPager = (ViewPager) findViewById(R.id.myfivepanelpager);
        myPager.setOnPageChangeListener(player);
        myPager.setAdapter(adapter);
        myPager.setCurrentItem(0);
        BG = MediaPlayer.create(this, R.raw.jingle);
        BG.setLooping(true);
        BG.setVolume(100, 100);
        BG.start();
        mp = MediaPlayer.create(Numbers.this, mAudio[0]);
        mp.start();
    }

    @Override
    protected void onPause() {
        super.onPause();
        BG.pause();
        }

    @Override
    protected void onResume() {
    super.onResume();
    BG.start();
    }

    private int[] mAudio = new int[]{R.raw.one,
                                     R.raw.two,
                                     R.raw.three,
                                     R.raw.four,
                                     R.raw.five,
                                     R.raw.six,
                                     R.raw.seven,
                                     R.raw.eight,
                                     R.raw.nine,
                                     R.raw.ten};

    private int imageArra[] =  {R.drawable.no1,
                                R.drawable.no2,
                                R.drawable.no3,
                                R.drawable.no4,
                                R.drawable.no5,
                                R.drawable.no6,
                                R.drawable.no7,
                                R.drawable.no8,
                                R.drawable.no9,
                                R.drawable.no10};

    public  OnPageChangeListener player = new OnPageChangeListener()
    {

        @Override
        public void onPageSelected(int arg1)
        {
        mp = MediaPlayer.create(Numbers.this, mAudio[arg1]);
        mp.start();
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2)
        {
        }

        @Override
        public void onPageScrollStateChanged(int arg0)
        {
        }
    };

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.numbers, menu);
        return true;
    }

}

Answer 3

它对我有用

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_farm_animals);
    ButterKnife.bind(this);
    farmAnimalAdapter = new FarmAnimalAdapter(this);
    viewPager.setOnPageChangeListener(players);
    viewPager.setAdapter(farmAnimalAdapter);

}
public int[] animal_images = new int[]{
        R.drawable.cow,
        R.drawable.sheep,
        R.drawable.horse,
        R.drawable.goat
};
public int[] animal_sound = new int[]{
        R.raw.cow,
        R.raw.sheep,
        R.raw.horse,
        R.raw.goat
};
public String[] names = new String[] {
        "COW","SHEEP","HORSE","GOAT"
};
ViewPager.OnPageChangeListener players= new ViewPager.OnPageChangeListener() {
    @Override
    public void onPageScrolled(int i, float v, int i1) {

    }

    @Override
    public void onPageSelected(int i) {
        //audio
        MediaPlayer sound = MediaPlayer.create(getApplicationContext(),animal_sound[i]);
        sound.start();
    }

    @Override
    public void onPageScrollStateChanged(int i) {

    }
};`   public class FarmAnimalAdapter extends PagerAdapter{
    Context mContext;
    LayoutInflater mLayoutInflater;


    public FarmAnimalAdapter(Context mContext) {
        this.mContext = mContext;
        this.mLayoutInflater = mLayoutInflater;
    }
    @Override
    public int getCount() {
        return names.length ;
    }
    @Override
    public boolean isViewFromObject(@NonNull View view, @NonNull Object object) {
        return view == object;
    }

    @NonNull
    @Override
    public Object instantiateItem(@NonNull ViewGroup container, int position) {
        mLayoutInflater =(LayoutInflater)mContext.getSystemService(LAYOUT_INFLATER_SERVICE);
        View view = mLayoutInflater.inflate(R.layout.farmanimal_adapter_list,container,false);
        ImageView txtimage = (ImageView)view.findViewById(R.id.txtimage);
        AppCompatTextView txtname = (AppCompatTextView)view.findViewById(R.id.txtname);
        txtimage.setImageResource(animal_images[position]);
        txtname.setText(names[position]);
        container.addView(view);
        return view;
    }

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

}

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