片段未从内存中释放

Question

我有一个活动,其中包含一个具有适配器FragmentStatePagerAdapter的View Pager.每次进入活动时,它将占用200mb的内存,在退回活动后(finish())然后重新输入它将附加并加倍手机上使用的内存.

在解决问题之后,似乎片段管理器没有释放片段,尽管我试图删除它们但它只是不起作用.

我尝试清空正在添加的片段以确保它不是片段内部的问题仍然存在.

我的适配器代码是

   private class ChildrenPagerAdapter extends FragmentStatePagerAdapter
   {
      private List<ChildBean> childrenBean;

      public ChildrenPagerAdapter(FragmentManager fm, List<ChildBean> bean)
      {
         super(fm);
         this.childrenBean = bean;
      }

      @Override
      public int getItemPosition(Object object)
      {
         return PagerAdapter.POSITION_NONE;
      }

      @Override
      public Fragment getItem(int position)
      {

         ReportFragment reportFragment = new ReportFragment();
         reportFragment.childBean = childrenBean.get(position);
         reportFragment.position = position;
         reportFragment.mPager = mPager;
         if(position == 0)
         {
            reportFragment.mostLeft = true;
         }
         if(position == childrenNumber - 1)
         {
            reportFragment.mostRight = true;
         }

         return reportFragment;
      }

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

      @Override
      public void destroyItem(ViewGroup container, int position, Object object)
      {
         // TODO Auto-generated method stub
         super.destroyItem(container, position, object);
      }
   }

我的活动代码是

    public class ReportActivity extends CustomActivity
{
   public ImageLoader imageLoader;
   private ViewPager mPager;
   private PagerAdapter mPagerAdapter;
   private int childrenNumber;
   private int currentChild;

   @Override
   protected void onDestroy()
   {
      mPager.removeAllViews();
      mPager.removeAllViewsInLayout();
      mPager.destroyDrawingCache();
      mPagerAdapter = null;
      mPager = null;
      System.gc();
      super.onDestroy();
   }

   @Override
   protected void onCreate(Bundle savedInstanceState)
   {

      super.onCreate(savedInstanceState);
      setCustomTitle(string.title_activity_reports);
      this.currentChild = getIntent().getIntExtra("itemselected", -1);

      getSupportFragmentManager().
   }

   @Override
   protected void onResume()
   {
      super.onResume();
      mPager = (ViewPager) findViewById(R.id.vpchildren);
      mPager.setOffscreenPageLimit(6);
      childrenNumber = MainActivity.bean.size();
      mPagerAdapter = new ChildrenPagerAdapter(getSupportFragmentManager(), MainActivity.bean);
      mPager.setAdapter(mPagerAdapter);
      mPager.setCurrentItem(currentChild);
   }
}

片段代码:

public class ReportFragment extends Fragment
{

   public ChildBean childBean;
   public int position;
   public ImageView img;
   public ImageLoader imageLoader;
   public DisplayImageOptions options;
   private int pee = 0;
   private int poop = 0;
   private double sleep = 0.0;
   public ViewPager mPager;
   public boolean mostLeft = false;
   public boolean mostRight = false;

   public ReportFragment()
   {

   }

   @Override
   public void onDestroyView()
   {
      super.onDestroyView();
   }

   @Override
   public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
   {
      ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.report_fragment, container, false);

      if(mostLeft)
      {
         rootView.findViewById(id.btnleft).setVisibility(View.GONE);
      }
      if(mostRight)
      {
         rootView.findViewById(id.btnright).setVisibility(View.GONE);
      }

      rootView.findViewById(id.btnleft).setOnClickListener(new OnClickListener()
      {

         @Override
         public void onClick(View v)
         {
            mPager.setCurrentItem(mPager.getCurrentItem() - 1);

         }
      });

      rootView.findViewById(id.btnright).setOnClickListener(new OnClickListener()
      {

         @Override
         public void onClick(View v)
         {
            mPager.setCurrentItem(mPager.getCurrentItem() + 1);

         }
      });

      SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy", Locale.ENGLISH);
      Date dobchild = new Date();

      ((TextView) rootView.findViewById(id.tvday)).setText(sdf.format(dobchild));

      ImageView childimg = (ImageView) rootView.findViewById(id.img_child);
      ((TextView) rootView.findViewById(id.tvchildname)).setText(childBean.childname);
      ((TextView) rootView.findViewById(id.tvclassname)).setText(((CustomApplication) getActivity().getApplication()).preferenceAccess.getCurrentClassName());

      Date dob = null;
      String age = "";
      try
      {
         dob = sdf.parse(childBean.childdob);
         age = GeneralUtils.getAge(dob.getTime(), getString(string.tv_day), getString(string.tv_month), getString(string.tv_year));
      }
      catch(ParseException e)
      {
         // TODO:
      }
      ((CustomTextView) rootView.findViewById(id.tvchildage)).setText(age);

      DisplayImageOptions options =
         new DisplayImageOptions.Builder().showImageForEmptyUri(drawable.noimage).showImageOnFail(drawable.noimage).showStubImage(drawable.noimage).cacheInMemory()
            .imageScaleType(ImageScaleType.NONE).build();

      imageLoader = ImageLoader.getInstance();
      imageLoader.displayImage(childBean.childphoto, childimg, options);
      final TextView tvpee = (TextView) rootView.findViewById(id.tvpeetime);
      final TextView tvpoop = (TextView) rootView.findViewById(id.tvpootimes);
      final TextView tvsleep = (TextView) rootView.findViewById(id.tvsleeptime);

      rootView.findViewById(id.btnaddpee).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            pee = pee + 1;
            if(pee > 9)
            {
               Toast.makeText(getActivity(), getString(string.tvareyousurepee), Toast.LENGTH_LONG).show();
            }
            tvpee.setText(String.format(getString(string.tvtimes), pee));
         }
      });

      rootView.findViewById(id.btnminuspee).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            if(pee > 0)
            {
               pee = pee - 1;
               tvpee.setText(String.format(getString(string.tvtimes), pee));
            }
         }
      });

      rootView.findViewById(id.btnpluspoo).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            poop = poop + 1;
            if(poop > 9)
            {
               Toast.makeText(getActivity(), getString(string.tvareyousurepoop), Toast.LENGTH_LONG).show();
            }
            tvpoop.setText(String.format(getString(string.tvtimes), poop));
         }
      });

      rootView.findViewById(id.btnminuspoo).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            if(poop > 0)
            {
               poop = poop - 1;
               tvpoop.setText(String.format(getString(string.tvtimes), poop));
            }
         }
      });

      rootView.findViewById(id.btnaddsleep).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            sleep = sleep + 0.25;
            tvsleep.setText(String.format(getString(string.tvhours), sleep));
         }
      });

      rootView.findViewById(id.btnminussleep).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            if(sleep > 0)
            {
               sleep = sleep - 0.25;
               tvsleep.setText(String.format(getString(string.tvhours), sleep));
            }
         }
      });

      rootView.findViewById(id.btnsave).setOnClickListener(new OnClickListener()
      {
         @Override
         public void onClick(View v)
         {
            Toast.makeText(getActivity(), "Report Saved.", Toast.LENGTH_LONG).show();
            getActivity().finish();
         }
      });

      return rootView;
   }
}

请指教......谢谢

Answer 1

ViewPager本身有一个方法setOffscreenPageLimit,允许您指定适配器保留的页数.所以远处的碎片将被摧毁.

首先看看你的代码我没有看到你在片段onDestroy()中做任何内存释放措施.片段本身被破坏和gc'ed的事实并不意味着你分配的所有资源也被删除了.

例如,我最担心的是:

imageLoader = ImageLoader.getInstance();
imageLoader.displayImage(childBean.childphoto, childimg, options);

从我在这里看到的似乎每次出现一个新片段时都会有一个静态的ImageLoader实例被戳戳,但我看不到一个垂死的片段会让ImageLoader卸载它的东西.这看起来很可疑.

如果我是你,我会在活动重启后花费额外的200mb(如你所声称的那样)转储我的应用程序的HPROF文件,并通过MAT(内存分析器工具)分析参考.您显然存在内存泄漏问题,我非常怀疑问题是Fragments本身没有被破坏.

如果你不知道如何分析内存堆,这是一个很好的视频.我无法计算它有多少次帮助我识别和消除我的应用程序中的内存泄漏.