Question

我有一个recyclerview，使用arraylist填充。当我从列表中删除项目时，它可以正常工作，直到最后一项被删除。下面是我的recyclerview适配器中的代码，它删除了一个项目。

public void removeItem(int position) {
        itemsData.remove(position);
        notifyItemRemoved(position);
    }

下面是崩溃日志。日志不会将我引导到我的代码中的指定位置。所以我不确定是什么导致了这个问题。

我做了一些测试并记录了位置。如果我在arraylist中添加一个项目并在recyclerview中添加项目的位置notifyItemInserted，则为0.如果我单击添加的项目，则位置为0，如果我删除该项目，则将其移除0，但在将项目移除为位置0时崩溃了。

java.lang.NullPointerException：尝试调用虚拟方法＆android; view.view. $ Home;在null对象引用上在android.support.v7.widget.OrientationHelper $ 2.getDecoratedStart（OrientationHelper.java:316）在android.support.v7.widget.LinearLayoutManager.findOneVisibleChild（LinearLayoutManager.java:1633）在android.support.v7.widget.LinearLayoutManager.findFirstVisibleChildClosestToStart（LinearLayoutManager.java:1453）在android.support.v7.widget.LinearLayoutManager.computeScrollOffset（LinearLayoutManager.java:997）在android.support.v7.widget.LinearLayoutManager.computeVerticalScrollOffset（LinearLayoutManager.java:969）在android.support.v7.widget.RecyclerView.computeVerticalScrollOffset（RecyclerView.java:1175）在android.view.View.canScrollVertically（View.java:12835）在android.support.v4.view.ViewCompatICS.canScrollVertically（ViewCompatICS.java:35）在android.support.v4.view.ViewCompat $ ICSViewCompatImpl.canScrollVertically（ViewCompat.java:1136）在android.support.v4.view.ViewCompat.canScrollVertically（ViewCompat.java:1528）在android.support.v7.widget.RecyclerView $ LayoutManager.onInitializeAccessibilityEvent（RecyclerView.java:6594）在android.support.v7.widget.RecyclerView $ LayoutManager.onInitializeAccessibilityEvent（RecyclerView.java:6573）在android.support.v7.widget.LinearLayoutManager.onInitializeAccessibilityEvent（LinearLayoutManager.java:204）在android.support.v7.widget.RecyclerViewAccessibilityDelegate.onInitializeAccessibilityEvent（RecyclerViewAccessibilityDelegate.java:66）在android.support.v4.view.AccessibilityDelegateCompat $ AccessibilityDelegateJellyBeanImpl $ 1.onInitializeAccessibilityEvent（AccessibilityDelegateCompat.java:228）在android.support.v4.view.AccessibilityDelegateCompatJellyBean $ 1.onInitializeAccessibilityEvent（AccessibilityDelegateCompatJellyBean.java:56）在android.view.View.onInitializeAccessibilityEvent（View.java:5439）在android.view.View.sendAccessibilityEventUncheckedInternal（View.java:5312）在android.view.View $ AccessibilityDelegate.sendAccessibilityEventUnchecked（View.java:20823）在android.support.v4.view.AccessibilityDelegateCompatIcs.sendAccessibilityEventUnchecked（AccessibilityDelegateCompatIcs.java:117）在android.support.v4.view.AccessibilityDelegateCompat $ AccessibilityDelegateIcsImpl.sendAccessibilityEventUnchecked（AccessibilityDelegateCompat.java:210）在android.support.v4.view.AccessibilityDelegateCompat.sendAccessibilityEventUnchecked（AccessibilityDelegateCompat.java:358）在android.support.v4.view.AccessibilityDelegateCompat $ AccessibilityDelegateJellyBeanImpl $ 1.sendAccessibilityEventUnchecked（AccessibilityDelegateCompat.java:255）在android.support.v4.view.AccessibilityDelegateCompatJellyBean $ 1.sendAccessibilityEventUnchecked（AccessibilityDelegateCompatJellyBean.java:82）在android.view.View.sendAccessibilityEventUnchecked（View.java:5297）在android.view.ViewRootImpl $ SendWindowContentChangedAccessibilityEvent.run（ViewRootImpl.java:6934）在android.view.ViewRootImpl $ SendWindowContentChangedAccessibilityEvent.runOrPost（ViewRootImpl.java:6960）在android.view.ViewRootImpl.postSendWindowContentChangedCallback（ViewRootImpl.java:6161）在android.view.ViewRootImpl.notifySubtreeAccessibilityStateChanged（ViewRootImpl.java:6274）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（ViewGroup.java:2772）在android.view.ViewGroup.notifySubtreeAccessibilityStateChanged（

非常感谢任何帮助！

Answer 1

检查“非空”，应该没问题。像这样：

public void removeItem(int position) {
       if(itemsData != null){
        itemsData.remove(position);
        notifyItemRemoved(position);
       }
}

希望这有帮助。

删除最后一项时，Recyclerview崩溃。 NullPointerException：android.view.ViewGroup $ LayoutParams android.view.View.getLayoutParams（）

1 个答案: