由于 PopupWindow 导致的内存泄漏

Question

我有一个 FragmentA。当我单击 FragmentA 中的按钮时，我会转到 FragmentB。在 FragmentB 我有一个 PopupWindow。 PopupWindow 有一个包含两个页面的 ViewPager。

我从这段代码中得到了帮助 - Emojicon

我有 2 个单独的类，View1 和 View2，分别用于 ViewPager 的第 1 页和第 2 页的视图。这两个类 View1 和 View2 都扩展了父类 ViewBase。

这是我的问题：

场景 1： 当我在 FragmentA 时，内存图显示 13MB 利用率。当我在不显示 PopupWindow 的情况下转到 FragmentB 时，内存图显示为 16MB，当我回到 FragmentA 时，它下降到 13MB。这很好。

场景 2： 当我在 FragmentA 时，内存图显示 13MB 利用率。当我通过显示 PopupWindow 转到 FragmentB 时，内存图显示为 20MB，而当我回到 FragmentA 时，它并没有下降到 13MB。

我尝试了 Eclipse MAT 和 Heap dump 来找出问题，但仍然没有帮助。我可以在 MAT 中看到，当我回到 FragmentA 并持有 PopupWindow、View1 和 View2 的实例时，FragmentB 仍在内存中。他们都没有被释放。 FragmentB 不应该在内存中。

请帮帮我。

这是我的 DemoPopupWindow.java

public class DemoPopupWindow extends PopupWindow {

// Views
private TabLayout mTabLayout;
private CustomViewPager mViewPager;
private PagerAdapter mViewPagerAdapter;
private RelativeLayout mLayout;
private View mRootView;

// Variables
private int mGreyColor, mPrimaryColor;
private OnSoftKeyboardOpenCloseListener onSoftKeyboardOpenCloseListener;
private int keyBoardHeight = 0;
private Boolean pendingOpen = false;
private Boolean isOpened = false;
private Context mContext;

ViewTreeObserver.OnGlobalLayoutListener mGlobalLayoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        Rect r = new Rect();
        mRootView.getWindowVisibleDisplayFrame(r);

        int screenHeight = mRootView.getRootView().getHeight();
        int heightDifference = screenHeight - (r.bottom);
        if (heightDifference > 100) {
            keyBoardHeight = heightDifference;
            setSize(WindowManager.LayoutParams.MATCH_PARENT, keyBoardHeight);
            if (isOpened == false) {
                if (onSoftKeyboardOpenCloseListener != null)
                    onSoftKeyboardOpenCloseListener.onKeyboardOpen(keyBoardHeight);
            }
            isOpened = true;
            if (pendingOpen) {
                showAtBottom();
                pendingOpen = false;
            }
        } else {
            isOpened = false;
            if (onSoftKeyboardOpenCloseListener != null)
                onSoftKeyboardOpenCloseListener.onKeyboardClose();
        }
    }
};

/**
 * Constructor
 * @param rootView
 * @param mContext
 */
public DemoPopupWindow(View rootView, Context mContext){
    super(mContext);
    this.mContext = mContext;
    this.mRootView = rootView;

    Resources resources = mContext.getResources();
    View customView = createCustomView(resources);

    setContentView(customView);
    setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
    setSize((int) mContext.getResources().getDimension(R.dimen.keyboard_height), WindowManager.LayoutParams.MATCH_PARENT);

}

/**
 * Set keyboard close listener
 * @param listener
 */
public void setOnSoftKeyboardOpenCloseListener(OnSoftKeyboardOpenCloseListener listener){
    this.onSoftKeyboardOpenCloseListener = listener;
}

/**
 * Show PopupWindow
 */
public void showAtBottom(){
    showAtLocation(mRootView, Gravity.BOTTOM, 0, 0);
}

/**
 * Show PopupWindow at bottom
 */
public void showAtBottomPending(){
    if(isKeyBoardOpen())
        showAtBottom();
    else
        pendingOpen = true;
}

/**
 * Check whether keyboard is open or not
 * @return
 */
public Boolean isKeyBoardOpen(){
    return isOpened;
}

/**
 * Set soft keyboard size
 */
public void setSizeForSoftKeyboard(){
    mRootView.getViewTreeObserver().addOnGlobalLayoutListener(mGlobalLayoutListener);
}

/**
 * Remove global layout listener
 */
public void removeGlobalListener() {
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
        mRootView.getViewTreeObserver().removeGlobalOnLayoutListener(mGlobalLayoutListener);
    } else {
        mRootView.getViewTreeObserver().removeOnGlobalLayoutListener(mGlobalLayoutListener);
    }
}

/**
 * Set PopupWindow size
 * @param width
 * @param height
 */
public void setSize(int width, int height){
    keyBoardHeight = height;
    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, keyBoardHeight);
    mLayout.setLayoutParams(params);
    setWidth(width);
    setHeight(height);
}

/**
 * Create PopupWindow View
 * @return
 */
private View createCustomView(Resources resources) {
    LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    View view = inflater.inflate(R.layout.popup, null, false);

    mViewPager = (CustomViewPager) view.findViewById(R.id.pager);
    mLayout = (RelativeLayout) view.findViewById(R.id.layout);

    mViewPagerAdapter = new ViewPagerAdapter(
            Arrays.asList(
                    new View1(mContext, this),
                    new View2(mContext, this)
            )
    );
    mViewPager.setAdapter(mViewPagerAdapter);

    mPrimaryColor = resources.getColor(R.color.color_primary);
    mGreyColor = resources.getColor(R.color.grey_color);

    mTabLayout = (TabLayout) view.findViewById(R.id.tabs);
    mTabLayout.addTab(mTabLayout.newTab());
    mTabLayout.addTab(mTabLayout.newTab());
    mTabLayout.setupWithViewPager(mViewPager);

    return view;
}

/**
 * ViewPager Adapter
 */
private static class ViewPagerAdapter extends PagerAdapter {
    private List<ViewBase> views;

    public ViewPagerAdapter(List<ViewBase> views) {
        super();
        this.views = views;
    }

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


    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        View v = views.get(position).mRootView;
        ((ViewPager)container).addView(v, 0);
        return v;
    }

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

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

/**
 * Soft keyboard open close listener
 */
public interface OnSoftKeyboardOpenCloseListener{
    void onKeyboardOpen(int keyBoardHeight);
    void onKeyboardClose();
}
}

请注意，我没有在此处粘贴完整的 PopupWindow 类，而只粘贴了必要的部分。

这是我在 FragmentB 中使用此 DemoPopupWindow 的方式

mPopupWindow = new DemoPopupWindow(mLayout, getActivity());
    mPopupWindow.setSizeForSoftKeyboard();


    // If the text keyboard closes, also dismiss the PopupWindow
    mPopupWindow.setOnSoftKeyboardOpenCloseListener(new DemoPopupWindow.OnSoftKeyboardOpenCloseListener() {

        @Override
        public void onKeyboardOpen(int keyBoardHeight) {

        }

        @Override
        public void onKeyboardClose() {
            if (mPopupWindow.isShowing())
                mPopupWindow.dismiss();
        }
    });

在 FragmentB 的 onDestroy 中我调用这个方法来移除 GlobalLayoutListener

mPopupWindow.removeGlobalListener();

我在 FragmentB 中有一个按钮来显示和关闭 PopupWindow。

这是我的 ViewBase.java

public class ViewBase {

public View mRootView;
DemoPopupWindow mPopup;
private Context mContext;

public ViewBase (Context context, DemoPopupWindow popup) {
    mContext = context;
    mPopup = popup;
}

public ViewBase () {
}
}

这是我的观点1

public class View1 extends ViewBase{

// Views
public View mRootView;
DemoPopupWindow mPopup;
private LinearLayout mLayoutText;

// Variables
private Context mContext;
private List<String> mText;

/**
 * Constructor
 */
public View1(Context context, DemoPopupWindow popup) {
    super(context, popup);

    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    mPopup = popup;
    mRootView = inflater.inflate(R.layout.fragment_view1, null);
    mContext = context;

    // Set parent class rootview
    super.mRootView = mRootView;

    registerViews(mRootView);
    registerListeners();

    populateText();
}

/**
 * Register all the views
 * @param view
 */
private void registerViews(View view) {
    mLayoutText = (LinearLayout) view.findViewById(R.id.view1_layout);
    mText = TextManager.getInstance().getText();
}

/**
 * Populate text
 */
private void populateText() {
    int length = mText.size();
    for(int i=0; i<length; i++) {
        addNewText(mText.get(i).getText());
    }
}

/**
 * Add new text
 * @param text
 */
private void addNewText(final String text) {
    TextView textView = createTextView(text);
    mLayoutText.addView(textView);
    textView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // Do something
        }
    });
}

/**
 * Create textview
 * @param text
 * @return
 */
private TextView createTextView(final String text) {
    TextView textView = new TextView(mContext);
    FlowLayout.LayoutParams params = new FlowLayout.LayoutParams(FlowLayout.LayoutParams.WRAP_CONTENT, 40);
    params.setMargins(4, 4, 0, 0);
    textView.setLayoutParams(params);
    textView.setClickable(true);
    textView.setGravity(Gravity.CENTER);
    textView.setPadding(10, 0, 10, 0);
    textView.setText(text);
    textView.setTextSize(20);
    return textView;
}
}

再次编辑：

我找到了问题，但我不知道如何解决它。问题出在 mGlobalLayoutListener 上。这是持有一些观点的参考。如果我根本不使用 GlobalLayoutListener，那么 FragmentB 实例将从内存中删除。

即使在调用 removeGlobalLayout() 之后，此侦听器也不会被释放。请帮帮我。

Answer 1

如何安全移除 GlobalLayoutListener ？ 注意您的 Android 版本，因为 api 已弃用！ :)

你可以试试这个

 if (Build.VERSION.SDK_INT < 16) {
        v.getViewTreeObserver().removeGlobalOnLayoutListener(listener);
    } else {
        v.getViewTreeObserver().removeOnGlobalLayoutListener(listener);
    }

Answer 2

您确定 CustomPopupWindow 会导致内存泄漏吗？您在运行堆转储之前是否进行了垃圾收集，也许根本没有泄漏..？ 当你回到fragmentA时，它在FragmentB中调用onDestroy并弹出？