使用PullToRefreshListView时遇到Item点击事件失效问题解决方法

最近在自己的项目中使用到了以下开源项目：

https://github.com/nanchen2251/pullToRefreshDemo

android:descendantFocusability

Defines the relationship between the ViewGroup and its descendants when looking for a View to take focus.

Must be one of the following constant values.

该属性是当一个为view获取焦点时，定义viewGroup和其子控件两者之间的关系。

属性的值有三种：

beforeDescendants：viewgroup会优先其子类控件而获取到焦点

afterDescendants：viewgroup只有当其子类控件不需要获取焦点时才获取焦点

blocksDescendants：viewgroup会覆盖子类控件而直接获得焦点

通常我们用到的是第三种，即在Item布局的根布局加上android:descendantFocusability=”blocksDescendants”的属性就好了，至此listview点击的灵异事件告一段落。心得：遇到不会不懂的地方除了网上查询资料之外，也可以多多去尝试每种属性的作用，多阅读官方文档(我始终觉得还是读原文的比翻译的理解的会更好)。

以上文字转于：https://www.cnblogs.com/eyu8874521/archive/2012/10/17/2727882.html

===============================================================

文章https://blog.csdn.net/android_gogogo/article/details/53376178

给出了一个布局layout文件作为示列，以下引自该列：

<ListView
                    android:descendantFocusability="blocksDescendants"
                    android:focusable="false"
                    android:divider="@drawable/leftxian1"
                    android:id="@+id/flfg_content"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                     />

listview item 中textview：

    <TextView
            android:focusable="true"
            android:padding="5dp"
            android:gravity="center_vertical"
            android:textColor="@color/black"
            android:id="@+id/text_law"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="wrap_content" ></TextView>

值得注意的是，文章：https://www.cnblogs.com/larrylawrence/p/5617038.html

给出了属性设置为 android:descendantFocusability="blocksDescendants" 的时候应该注意的其它问题：

原文如下：

===============================================================

值得注意的是，ListView中的控件不能设置clickable="true"，否则会无视父控件的blockDescendants。

可参考：

https://segmentfault.com/q/1010000005800016

同理，如果一个cardview里面有个listview，这个listview如果设置了clickable="true"，遮住cardview的部分也是无法响应的。

===============================================================

http://flysnow.iteye.com/blog/1762556

中给出了更详尽的解释，如下：

Android ViewGroup.setDescendantFocusability函数

这个函数是在ViewGroup里定义的，主要用于控制child View获取焦点的能力，比如是否阻止child View获取焦点。

他有三个常量可供设置

FOCUS_BEFORE_DESCENDANTS ViewGroup本身先对焦点进行处理，如果没有处理则分发给child View进行处理
FOCUS_AFTER_DESCENDANTS 先分发给Child View进行处理，如果所有的Child View都没有处理，则自己再处理
FOCUS_BLOCK_DESCENDANTS ViewGroup本身进行处理，不管是否处理成功，都不会分发给ChildView进行处理

Setdescendantfocusability(int focusability)代码

    public void setDescendantFocusability(int focusability) {
            switch (focusability) {
                case FOCUS_BEFORE_DESCENDANTS:
                case FOCUS_AFTER_DESCENDANTS:
                case FOCUS_BLOCK_DESCENDANTS:
                    break;
                default:
                    throw new IllegalArgumentException("must be one of FOCUS_BEFORE_DESCENDANTS, "
                            + "FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS");
            }
            mGroupFlags &= ~FLAG_MASK_FOCUSABILITY;
            mGroupFlags |= (focusability & FLAG_MASK_FOCUSABILITY);
        }

可以看到，只有这三个常量可以设置，不是这三个常量会抛出异常的。

设置后，会在requestFocus(int direction, Rect previouslyFocusedRect) 方法里根据设置进行相应的处理。来看下实现

Requestfocus(int direction, rect previouslyfocusedrect)代码

    public boolean requestFocus(int direction, Rect previouslyFocusedRect) {
            if (DBG) {
                System.out.println(this + " ViewGroup.requestFocus direction="
                        + direction);
            }
            int descendantFocusability = getDescendantFocusability();  
 
            switch (descendantFocusability) {
                case FOCUS_BLOCK_DESCENDANTS:
                    return super.requestFocus(direction, previouslyFocusedRect);
                case FOCUS_BEFORE_DESCENDANTS: {
                    final boolean took = super.requestFocus(direction, previouslyFocusedRect);
                    return took ? took : onRequestFocusInDescendants(direction, previouslyFocusedRect);
                }
                case FOCUS_AFTER_DESCENDANTS: {
                    final boolean took = onRequestFocusInDescendants(direction, previouslyFocusedRect);
                    return took ? took : super.requestFocus(direction, previouslyFocusedRect);
                }
                default:
                    throw new IllegalStateException("descendant focusability must be "
                            + "one of FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS "
                            + "but is " + descendantFocusability);
            }
        }

=========================================================================

文章

https://segmentfault.com/q/1010000005800016

给出了其它的几种解决方法，个人觉得还是有可能搞定，不过由于个人客观因素所限制并没有给出具体实现验证，下面给出其中内容：

参考：
https://developer.android.com/reference/android/view/ViewGroup.html#onInterceptTouchEvent(android.view.MotionEvent)