簡體   English   中英

嵌套的 RecyclerView。 如何防止父 RecyclerView 在子 RecyclerView 滾動時滾動?

[英]Nested RecyclerView. How to prevent parent RecyclerView from getting scrolled while child RecyclerView is scrolling?

我想實現一個水平recyclerview和每個項目recyclerview將是一個垂直recyclerview與網格布局。 我面臨的問題是,當我嘗試垂直滾動子recyclerview有時父recyclerview會滾動並開始水平滾動。 我試圖解決這個問題的方法是,

  1. recyclerview setNestedScrollingEnabled(false)上的setNestedScrollingEnabled(false)
  2. 在子recyclerview onTouch()中,我通過調用requestdisallowinterceptTouchevent(false)禁用父recyclerview requestdisallowinterceptTouchevent(false)上的觸摸事件

上述解決方案都沒有為問題提供完美的解決方案。 任何幫助表示贊賞

這個問題對我來說似乎很有趣。 所以我嘗試實現,這就是我所實現的(你也可以在這里看到視頻),非常流暢。

在此處輸入圖片說明

所以你可以嘗試這樣的事情:

定義CustomLinearLayoutManager擴展LinearLayoutManager像這樣:

public class CustomLinearLayoutManager extends LinearLayoutManager {

    public CustomLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
        super(context, orientation, reverseLayout);
    }

    @Override
    public boolean canScrollVertically() {
        return false;
    }
}

並將這個CustomLinearLayoutManager設置為您的父RecyclerView

RecyclerView parentRecyclerView = (RecyclerView)findViewById(R.id.parent_rv);
CustomLinearLayoutManager customLayoutManager = new CustomLinearLayoutManager(this, LinearLayoutManager.HORIZONTAL,false);
parentRecyclerView.setLayoutManager(customLayoutManager);
parentRecyclerView.setAdapter(new ParentAdapter(this)); // some adapter

現在對於子RecyclerView ,定義擴展GridLayoutManager自定義CustomGridLayoutManager

public class CustomGridLayoutManager extends GridLayoutManager {

    public CustomGridLayoutManager(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    public CustomGridLayoutManager(Context context, int spanCount) {
        super(context, spanCount);
    }

    public CustomGridLayoutManager(Context context, int spanCount, int orientation, boolean reverseLayout) {
        super(context, spanCount, orientation, reverseLayout);
    }

    @Override
    public boolean canScrollHorizontally() {
        return false;
    }
}

並將其設置為layoutManger到子RecyclerView

childRecyclerView = (RecyclerView)itemView.findViewById(R.id.child_rv);
childRecyclerView.setLayoutManager(new CustomGridLayoutManager(context, 3));
childRecyclerView.setAdapter(new ChildAdapter()); // some adapter

所以基本上父RecyclerView水平滾動,子RecyclerView垂直滾動。

除此之外,如果您還想處理對角滑動(幾乎不偏向垂直或水平),您可以在RecylerView包含一個手勢偵聽RecylerView

public class ParentRecyclerView extends RecyclerView {

    private GestureDetector mGestureDetector;

    public ParentRecyclerView(Context context) {
        super(context);
        mGestureDetector = new GestureDetector(this.getContext(), new XScrollDetector());
       // do the same in other constructors
    }

   // and override onInterceptTouchEvent

   @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        return super.onInterceptTouchEvent(ev) && mGestureDetector.onTouchEvent(ev);
    }

}

XScrollDetector在哪里

class XScrollDetector extends GestureDetector.SimpleOnGestureListener {
        @Override
        public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
            return Math.abs(distanceY) < Math.abs(distanceX);
        }
}

因此ParentRecyclerView要求子視圖(在我們的例子中是 VerticalRecyclerView)來處理滾動事件。 如果子視圖處理,那么父級什么都不做,父級最終會處理滾動。

父回收站視圖上的 setNestedScrollingEnabled(false)

您可以嘗試在RecyclerView 上使用setNestedScrollingEnabled(false)如果有)。 RecyclerView 的nestedscroll-ness 是一個孩子的(這就是它實現NestedScrollingChild的原因)。

在子回收器視圖的 onTouch() 中,我通過調用 requestdisallowinterceptTouchevent(false) 禁用父回收器視圖上的觸摸事件

這應該可行,但您應該做的是requestDisallowInterceptTouchEvent(true) ,而不是false 如果子類化 RecyclerView,則可以覆蓋onTouchEvent

@Override
public boolean onTouchEvent(MotionEvent event) {
    if (MotionEventCompat.getActionMasked(event) == MotionEvent.ACTION_UP) {
        // ensure we release the disallow request when the finger is lifted
        getParent().requestDisallowInterceptTouchEvent(false);
    } else {
        getParent().requestDisallowInterceptTouchEvent(true);
    }
    // Call the super class to ensure touch handling
    return super.onTouchEvent(event);
}

或者,使用外部的觸摸監聽器,

child.setOnTouchListener(new View.OnTouchListener() {

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if (v.getId() == child.getId()) {
            if (MotionEventCompat.getActionMasked(event) == MotionEvent.ACTION_UP) {
                // ensure we release the disallow request when the finger is lifted
                child.getParent().requestDisallowInterceptTouchEvent(false);
            } else {
                child.getParent().requestDisallowInterceptTouchEvent(true);
            }
        }
        // Call the super class to ensure touch handling
        return super.onTouchEvent(event);
    }
});

我在一個類似的項目中通過對你(以及這里的其他人)采取相反的方法來解決這個問題。

我沒有讓孩子告訴父母什么時候停止查看事件,而是讓父母決定什么時候忽略(根據方向)。 這種方法需要一個自定義視圖,但這可能需要更多的工作。 下面是我創建的將用作外部/父視圖的內容。

public class DirectionalRecyclerView extends RecyclerView {

    private static float LOCK_DIRECTION_THRESHOLD; //The slop
    private float startX;
    private float startY;
    private LockDirection mLockDirection = null;

    public DirectionalRecyclerView(Context context) {
        super(context);
        findThreshold(context);
    }

    public DirectionalRecyclerView(Context context, AttributeSet attrs) {
        super(context, attrs);
        findThreshold(context)
    }

    public DirectionalRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        findThreshold(context);
    }

    private void findThreshold(Context context) {
        //last number is number of dp to move before deciding that's a direction not a tap, you might want to tweak it
        LOCK_DIRECTION_THRESHOLD = context.getResources().getDisplayMetrics().density * 12;
    }

    //events start at the top of the tree and then pass down to
    //each child view until they reach where they were initiated
    //unless the parent (this) method returns true for this visitor
    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                startX = event.getX();
                startY = event.getY();
                break;
            case MotionEvent.ACTION_MOVE:
                if (mLockDirection == null) {
                    float currentX = event.getX();
                    float currentY = event.getY();
                    float diffX = Math.abs(currentX - startX);
                    float diffY = Math.abs(currentY - startY);
                    if (diffX > LOCK_DIRECTION_THRESHOLD) {
                        mLockDirection = LockDirection.HORIZONTAL;
                    } else if (diffY > LOCK_DIRECTION_THRESHOLD) {
                        mLockDirection = LockDirection.VERTICAL;
                    }
                } else {
                    //we have locked a direction, check whether we intercept
                    //the future touches in this event chain
                    //(returning true steals children's events, otherwise we'll
                    // just let the event trickle down to the child as usual)
                    return mLockDirection == LockDirection.HORIZONTAL;
                }
                break;
            case MotionEvent.ACTION_UP:
                mLockDirection = null;
                break;
        }
        //dispatch cancel, clicks etc. normally
        return super.onInterceptTouchEvent(event);
    }

    private enum LockDirection {
        HORIZONTAL,
        VERTICAL
    }

}

現在你可以試試android:nestedScrollingEnabled因為谷歌修復了使用nestedScrollingEnabled的崩潰(問題197932)

將偵聽器設置為嵌套的 RecyclerView

 View.OnTouchListener listener = new View.OnTouchListener() {
                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    if (event.getAction() == MotionEvent.ACTION_MOVE
                            ) {
                        v.getParent().requestDisallowInterceptTouchEvent(true);

                    } else {
                        v.getParent().requestDisallowInterceptTouchEvent(false);

                    }
                    return false;
                }
            };

            mRecyclerView.setOnTouchListener(listener);

試試這個。 對於我的用例,它起作用了:

nestedRecyclerView.setOnTouchListener(new View.OnTouchListener() {

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return true;
    }
});

試試下面的代碼,希望它會起作用。

nestedRecyclerView.setOnTouchListener(new View.OnTouchListener() {
                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    int action = event.getAction();
                   switch (action) {
                  case MotionEvent.ACTION_DOWN:
                     // Disallow parent to intercept touch events.
                     v.getParent().requestDisallowInterceptTouchEvent(true);
                     break;

                 case MotionEvent.ACTION_UP:
                    // Allow parent to intercept touch events.
                    v.getParent().requestDisallowInterceptTouchEvent(false);
            break;
        }

                  // Handle inner(child) touch events.
                    v.onTouchEvent(event);
        return true;
                }
            });

嘗試下面的代碼來滾動內部 RecyclerView。

innerRecyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {

        @Override
        public void onTouchEvent(RecyclerView recycler, MotionEvent event) {
            // Handle on touch events here
            int action = event.getAction();
            switch (action) {
                case MotionEvent.ACTION_DOWN:
                    // Disallow Parent RecyclerView to intercept touch events.
                    recycler.getParent().requestDisallowInterceptTouchEvent(true);
                    break;

                case MotionEvent.ACTION_UP:
                    // Allow Parent RecyclerView to intercept touch events.
                    recycler.getParent().requestDisallowInterceptTouchEvent(false);
                    break;
            }


        }

        @Override
        public boolean onInterceptTouchEvent(RecyclerView recycler, MotionEvent event) {
            return false;
        }

    });

IMO,您可以在外部 RecyclerView 的 Adapter 中嘗試以下操作:

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview, parent, false);

        RVAdapter2 recyclerViewAdapter2 = new RVAdapter2();
        RecyclerView innerRV = (RecyclerView) v.findViewById(R.id.rv2);
        // Setup layout manager for items
        LinearLayoutManager layoutManager2 = new LinearLayoutManager(parent.getContext());
        // Control orientation of the items
        layoutManager2.setOrientation(LinearLayoutManager.VERTICAL);
        innerRV.setLayoutManager(layoutManager2);
        innerRV.setAdapter(recyclerViewAdapter2);

        innerRV.setOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
                recyclerView.getParent().requestDisallowInterceptTouchEvent(true);
            }
        });

        return new MyViewHolder(v);
    }

對於 API23,您也可以嘗試innerRV.setOnScrollChangeListener因為setOnScrollListener已被棄用。

更新:

另一種選擇是使用addOnScrollListener而不是setOnScrollListener

希望有幫助!

使用此代碼關閉recyclerview滾動:

recyclerView.setOnTouchListener(new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return true;
    }
});

你應該這樣做:

innerRecyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {

        @Override
        public void onTouchEvent(RecyclerView recycler, MotionEvent event) {
            // Handle on touch events here
            int action = event.getAction();
            switch (action) {
                case MotionEvent.ACTION_DOWN:

                    recycler.getParent().requestDisallowInterceptTouchEvent(true);

                    break;

                case MotionEvent.ACTION_UP:

                    recycler.getParent().requestDisallowInterceptTouchEvent(false);

                    break;

                case MotionEvent.ACTION_MOVE:

                    recycler.getParent().requestDisallowInterceptTouchEvent(true);

                    break;
            }


        }

        @Override
        public boolean onInterceptTouchEvent(RecyclerView recycler, MotionEvent event) {
            return false;
        }

    });

希望這會幫助你。

我對單元使用卡片視圖,並在子適配器中使用子單元setOnClickListener停用父回收器視圖滾動。

holder.itemView.setOnTouchListener { view, _ ->
    view.parent.parent.requestDisallowInterceptTouchEvent(true)
    false
}

我們呼吁view.parent.parent因為事實itemView是一元布局和它的母公司是我們的孩子recyclerView而且,我們需要達到的孩子recyclerView的父母,防止家長recyclerView滾動。

該問題存在於 Android 對 RecyclerView 的 onInterceptTouchEvent() 方法的實現中。 這個博客指出了這個問題並修復了它 - http://nerds.headout.com/fix-horizo​​ntal-scrolling-in-your-android-app/ 唯一的區別是父級垂直滾動而子級水平滾動。 但是該解決方案注意它也應該適用於您的情況。

像這樣擴展自定義布局管理器

 public class CustomLayoutManager extends LinearLayoutManager {
 private boolean isScrollEnabled = true;

 public CustomGridLayoutManager(Context context) {
 super(context);
        }
  @Override
 public boolean canScrollVertically() {
 return false;
 }
}

將布局管理器設置為此“自定義布局管理器”

暫無
暫無

聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM