Pager适配器崩溃

Question

我有一个pageradapter，我用来显示图像幻灯片，但它崩溃时，我设置较低的屏幕限制。

这里是我的代码

public class ProjectPicturesAdapter extends PagerAdapter { 

private List<String> pictures; 
private LayoutInflater inflater; 
private final RequestManager glide; 

public ProjectPicturesAdapter(RequestManager glide, LayoutInflater inflater, List<String> pictures) { 
    this.pictures = pictures; 
    this.glide = glide; 
    this.inflater = inflater; 
} 

@Override 
public Object instantiateItem(ViewGroup container, int position) { 
    View image = inflater.inflate(R.layout.slider_image, container, false); 
    ImageView myImage = (ImageView) image.findViewById(R.id.image); 

    glide.load(pictures.get(position)) 
      .centerCrop() 
      .crossFade() 
      .placeholder(R.drawable.project_placeholder) 
      .into(myImage); 
    container.addView(myImage); 
    return myImage; 
} 

@Override 
public void destroyItem(ViewGroup container, int position, Object view) { 
    container.removeView((View) view); 
} 


@Override 
public int getCount() { 
    return pictures.size(); 
} 

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

} 

我正在初始化适配器的方式是这样的

 ProjectPicturesAdapter picturesAdapter = new 
     ProjectPicturesAdapter(Glide.with(this), LayoutInflater.from(this), 
     images); 

     ViewPager pager = (ViewPager) findViewById(R.id.viewPager); 
     pager.setAdapter(picturesAdapter); 
     pager.setOffscreenPageLimit(1); 

如果有2倍以上的图像，然后它崩溃了，我可以随时增加戏外极限但如果有20张图片会发生什么情况，我无法将屏幕外限制保持为20.

我的故障日志出现错误，说明指定的孩子已经有父母。您必须先调用子对象的父对象的removeView（）。

Answer 1

更新ProjectPicturesAdapter如下：

public class ProjectPicturesAdapter extends PagerAdapter { 

private List<String> pictures; 
private LayoutInflater inflater; 
private final RequestManager glide; 

public ProjectPicturesAdapter(RequestManager glide, LayoutInflater inflater, List<String> pictures) { 
    this.pictures = pictures; 
    this.glide = glide; 
    this.inflater = inflater; 
} 

@Override 
public Object instantiateItem(ViewGroup container, int position) { 
    ViewGroup view = (ViewGroup) inflater.inflate(R.layout.slider_image, container, false); 
    ImageView myImage = (ImageView) view.findViewById(R.id.image); 

    glide.load(pictures.get(position)) 
      .centerCrop() 
      .crossFade() 
      .placeholder(R.drawable.project_placeholder) 
      .into(myImage); 

    container.addView(view); 

    return view; 
} 

@Override 
public void destroyItem(ViewGroup container, int position, Object view) { 
    container.removeView((View) view); 
} 

@Override 
public int getCount() { 
    return pictures.size(); 
} 

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

} 

Answer 2

如果您的目的是展示旋转木马？ 只要使用这个库，你的问题将得到解决https://github.com/sayyam/carouselview

Answer 3

问题是由这个原因引起：

@Override 
public void destroyItem(ViewGroup container, int position, Object view) 
{ 
    container.removeView((View) view); 
} 

我建议使用FragmentStatePagerAdapter而不是PagerAdapter。

public static class MyAdapter extends FragmentStatePagerAdapter { 
    public MyAdapter(FragmentManager fm) { 
     super(fm); 
    } 

    @Override 
    public int getCount() { 
     return NUM_ITEMS; 
    } 

    @Override 
    public Fragment getItem(int position) { 
     return ArrayListFragment.newInstance(position); 
    } 
} 

---

mAdapter = new MyAdapter(getFragmentManager()); 

mPager = (ViewPager)findViewById(R.id.pager); 
mPager.setAdapter(mAdapter);