!578 增加ScrollTop和ScrollBottom事件

Merge pull request !578 from 郝烁/master

frameworks/components/ui_list.cpp

@@ -354,6 +354,31 @@ bool UIList::MoveOffset(int16_t x, int16_t y)
         scrollListener_->OnScrollStart(onSelectedIndex_, onSelectedView_);
     }
 
+    if (!isLoopList_ && scrollListener_) {
+        if (direction_ == VERTICAL) {
+            if (childrenHead_ && (childrenHead_->GetViewIndex() == startIndex_) &&
+                childrenHead_->GetRelativeRect().GetTop() >= 0 &&
+                childrenHead_->GetRelativeRect().GetTop() - y < 0) {
+                scrollListener_->OnScrollTop(childrenHead_->GetViewIndex(), childrenHead_);
+            }
+            if (childrenTail_ && (childrenTail_->GetViewIndex() == recycle_.GetAdapterItemCount()-1) &&
+                (childrenTail_->GetRelativeRect().GetBottom() <= GetContentRect().GetHeight() - 1) &&
+                (childrenTail_->GetRelativeRect().GetBottom() - y > GetContentRect().GetHeight() - 1)) {
+                    scrollListener_->OnScrollBottom(childrenTail_->GetViewIndex(), childrenTail_);
+            }
+        } else {
+            if (childrenHead_ && (childrenHead_->GetViewIndex() == startIndex_) &&
+                childrenHead_->GetRelativeRect().GetLeft() >= 0 &&
+                childrenHead_->GetRelativeRect().GetLeft() - x < 0) {
+                scrollListener_->OnScrollTop(childrenHead_->GetViewIndex(), childrenHead_);
+            }
+            if (childrenTail_ && (childrenTail_->GetViewIndex() == recycle_.GetAdapterItemCount()-1) &&
+                (childrenTail_->GetRelativeRect().GetRight() <= GetContentRect().GetWidth() - 1) &&
+                (childrenTail_->GetRelativeRect().GetRight() - x > GetContentRect().GetWidth() - 1)) {
+                scrollListener_->OnScrollBottom(childrenTail_->GetViewIndex(), childrenTail_);
+            }
+        }
+    }
     return true;
 }
 

interfaces/kits/components/ui_list.h

@@ -93,6 +93,32 @@ public:
      */
     virtual void OnScrollEnd(int16_t index, UIView* view) {}
 
+    /**
+     * @brief Called when move to the top of scroll.
+     *
+     * @param index Indicates the index of the child view being selected at the preset position. This parameter should
+     *              be set to {@link NULL_SELECT_INDEX} if no child view is selected or no position is preset.
+     * @param view Indicates the child view being selected at the preset position. This parameter should be set to
+     *             <b>NULL</b> if no child view is selected or no position is preset.
+     * @since 8
+     * @version 8
+     *
+     */
+    virtual void OnScrollTop(int16_t index, UIView* view) {}
+
+    /**
+     * @brief Called when move to the bottom of scroll.
+     *
+     * @param index Indicates the index of the child view being selected at the preset position. This parameter should
+     *              be set to {@link NULL_SELECT_INDEX} if no child view is selected or no position is preset.
+     * @param view Indicates the child view being selected at the preset position. This parameter should be set to
+     *             <b>NULL</b> if no child view is selected or no position is preset.
+     * @since 8
+     * @version 8
+     *
+     */
+    virtual void OnScrollBottom(int16_t index, UIView* view) {}
+
     /**
      * @brief Called when a new child view is selected at the preset position as this list scrolls. For details about
      * how to set the position, see {@link SetSelectPosition}.