Github user cxfeng1 commented on a diff in the pull request:
https://github.com/apache/incubator-weex/pull/539#discussion_r129747478
--- Diff: ios/sdk/WeexSDK/Sources/Component/Recycler/WXRecyclerComponent.m
---
@@ -655,6 +707,166 @@ - (void)fixFlicker
});
}
+#pragma mark - dragMethod
+- (void)longPressMethod:(UILongPressGestureRecognizer*)gesture
+{
+if (_isDragable) {
+switch (gesture.state) {
+case UIGestureRecognizerStateBegan:
+[self dragBegin:gesture];
+break;
+case UIGestureRecognizerStateChanged:
+[self dragChanged:gesture];
+break;
+case UIGestureRecognizerStateEnded:
+[self dragEnd:gesture];
+break;
+default:
+break;
+}
+}
+}
+
+- (void)dragBegin:(UILongPressGestureRecognizer *)gesture{
+
+CGPoint point = [gesture locationInView:_collectionView];
+
+_startIndexPath = [self getDragingIndexPathWithPoint:point];
+if (!_startIndexPath) {
+return;
+}
+
+[self fireEvent:@"dragstart" params:@{@"fromIndex":[NSString
stringWithFormat:@"%ld",(long)_startIndexPath.row]}];
+
+_dragingIndexPath = [self getDragingIndexPathWithPoint:point];
+if (!_dragingIndexPath) {
+return;
+}
+
+[_collectionView bringSubviewToFront:_dragingCell];
+_dragingCell.frame = [_collectionView
cellForItemAtIndexPath:_dragingIndexPath].frame;
+_dragingCell.hidden = false;
+[UIView animateWithDuration:0.3 animations:^{
+[_dragingCell setTransform:CGAffineTransformMakeScale(1.2, 1.2)];
+}];
+}
+
+- (void)dragChanged:(UILongPressGestureRecognizer *)gesture{
+
+if (!_startIndexPath) {
+return;
+}
+CGPoint point = [gesture locationInView:_collectionView];
+_dragingCell.center = point;
+_targetIndexPath = [self getTargetIndexPathWithPoint:point];
+
+if (_targetIndexPath && _dragingIndexPath && (_targetIndexPath.section
== _startIndexPath.section)){
+[_collectionView moveItemAtIndexPath:_dragingIndexPath
toIndexPath:_targetIndexPath];
+_dragingIndexPath = _targetIndexPath;
+}
+}
+
+- (void)dragEnd:(UILongPressGestureRecognizer *)gesture{
+
+if (!_startIndexPath || !_dragingIndexPath) {
+return;
+}
+
+[self fireEvent:@"dragend" params:@{@"toIndex":[NSString
stringWithFormat:@"%ld",(long)_dragingIndexPath.row],@"fromIndex":[NSString
stringWithFormat:@"%ld",(long)_startIndexPath.row]}];
+
+CGRect endFrame = [_collectionView
cellForItemAtIndexPath:_dragingIndexPath].frame;
+
+__weak typeof(self) weakSelf = self;
+[UIView animateWithDuration:0.3 animations:^{
+[weakSelf.dragingCell setTransform:CGAffineTransformMakeScale(1.0,
1.0)];
+weakSelf.dragingCell.frame = endFrame;
+} completion:^(BOOL finished) {
+weakSelf.dragingCell.hidden = YES;
+NSMutableArray *oldComponents = [[NSMutableArray alloc]
initWithArray:weakSelf.dataController.sections[weakSelf.startIndexPath.section].cellComponents];
+if(oldComponents.count > 1){
+WXCellComponent *startComponent =
weakSelf.dataController.sections[weakSelf.startIndexPath.section].cellComponents[weakSelf.startIndexPath.item];
+[oldComponents removeObject:startComponent];
+[oldComponents insertObject:startComponent
atIndex:weakSelf.targetIndexPath.item];
+
weakSelf.dataController.sections[weakSelf.startIndexPath.section].cellComponents
= oldComponents;
+}
+}];
+}
+
+- (NSIndexPath *)getDragingIndexPathWithPoint:(CGPoint)point{
+NSIndexPath *dragingIndexPath = nil;
+for (NSIndexPath *indexPath in [_collectionView
indexPathsForVisibleItems]){
+if (CGRectContainsPoint([_collectionView
cellForItemAtIndexPath:indexPath].frame,point)) {
+dragingIndexPath = indexPath;
+break;
+}
+}
+
+BOOL isExcluded = NO;
+if (dragingIndexPath) {
+for (NSIndexPath *indexPath in _excludedAry) {
+if (indexPath.row == dragingIndexPath.row) {
+isExcluded = YES;
+}
+}
+}
+return isExcluded?nil:dragingIndexPath;
+}
+
+- (NSIndexPath *)getTargetIndexPathWithPoint:(CGPoint)point{
+NSIndexPath *targetIndexPath = nil;
+for (NSIndexPath *indexPath in
_collectionView.indexPathsForVisibleItems) {
+if (CGRectContainsPoint([_collectionView
cel
