ipad：将 UITableViewCell 从一个 UITableViewController 拖放到另一个
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【中文标题】ipad：将 UITableViewCell 从一个 UITableViewController 拖放到另一个【英文标题】：ipad: Drag a UITableViewCell from one UITableViewController and drop it into another 【发布时间】：2011-09-24 07:37:12 【问题描述】：我的问题是，这是否可能，如果可以，您将如何处理这项任务？
是否有人知道已经使用此功能的应用程序，或者从哪里获得一些示例代码？
另外，如果我要在不了解该主题的情况下自行实现此功能，您估计完成它需要多长时间？
还有一件事要提一下，因为它可能会使事情变得更复杂：目标表默认处于编辑模式，以便用户可以重新排列已删除的单元格（使用附件视图中的标准重新排序控件）在那里。
编辑：
我只是尝试在我的帖子中包含概念图像的屏幕截图。图像在左侧显示了一个表格，在右侧显示了一个灰色的放置区域。我的客户说他也在其他应用上看到了这个，所以肯定有某种我不知道的 ui 元素。
我在开发者库中没有找到任何关于这样一个放置区域的信息，所以希望你们中的某个人能给我指路或清理一下。
【问题讨论】：
看看这个：github.com/Ice3SteveFortune/i3-dragndrop 【参考方案1】：好的，我自己实现了这个，我对结果很满意。您可以将单元格从左侧（源表）拖动到右侧（目标表），也可以在目标表中拖动单元格进行重新排序。如果您尝试从右向左拖动一个单元格，它将重新插入到您开始拖动的相同位置（因此没有任何反应）。目标表还支持删除单元格，源表不支持。完整代码如下：
UIDropTableViewController.h
#import <UIKit/UIKit.h>
@interface UIDropTableViewController : UIViewController <UITableViewDelegate, UITableViewDataSource, UIGestureRecognizerDelegate>
UINavigationItem* srcTableNavItem;
UINavigationItem* dstTableNavItem;
UITableView* srcTableView;
UITableView* dstTableView;
UITableViewCell* draggedCell;
UIView* dropArea;
NSMutableArray* srcData;
NSMutableArray* dstData;
id draggedData;
BOOL dragFromSource; // used for reodering
NSIndexPath* pathFromDstTable; // used to reinsert data when reodering fails
@property (nonatomic, readonly) NSArray* srcData;
@property (nonatomic, readonly) NSArray* dstData;
- (id)initWithFrame:(CGRect)frame SourceData:(NSArray*)sourceData DestinationData:(NSArray*)destinationData;
- (void)setSrcTableTitle:(NSString*)title;
- (void)setDstTableTitle:(NSString*)title;
@end
UIDropTableViewController.m
#import "UIDropTableViewController.h"
#define kCellIdentifier @"DropTableCell"
#define kCellHeight 44
#define kNavBarHeight 30
// forward declaration of private helper methods
@interface UIDropTableViewController()
- (void)setupSourceTableWithFrame:(CGRect)frame;
- (void)setupDestinationTableWithFrame:(CGRect)frame;
- (void)initDraggedCellWithCell:(UITableViewCell*)cell AtPoint:(CGPoint)point;
- (void)startDragging:(UIPanGestureRecognizer *)gestureRecognizer;
- (void)startDraggingFromSrcAtPoint:(CGPoint)point;
- (void)startDraggingFromDstAtPoint:(CGPoint)point;
- (void)doDrag:(UIPanGestureRecognizer *)gestureRecognizer;
- (void)stopDragging:(UIPanGestureRecognizer *)gestureRecognizer;
- (UITableViewCell*)srcTableCellForRowAtIndexPath:(NSIndexPath*)indexPath;
- (UITableViewCell*)dstTableCellForRowAtIndexPath:(NSIndexPath*)indexPath;
@end
@implementation UIDropTableViewController
@synthesize srcData, dstData;
#pragma mark -
#pragma mark Public Methods
- (void)setSrcTableTitle:(NSString*)title
srcTableNavItem.title = title;
- (void)setDstTableTitle:(NSString*)title
dstTableNavItem.title = title;
#pragma mark -
#pragma mark UIViewController
- (id)initWithFrame:(CGRect)frame SourceData:(NSArray*)sourceData DestinationData:(NSArray*)destinationData
self = [super init];
if (self)
self.view.clipsToBounds = YES;
self.view.frame = frame;
int width = frame.size.width;
int height = frame.size.height;
// set up data
srcData = [[NSMutableArray alloc] initWithArray:sourceData];
dstData = [[NSMutableArray alloc] initWithArray:destinationData];
draggedCell = nil;
draggedData = nil;
pathFromDstTable = nil;
// set up views
[self setupSourceTableWithFrame:CGRectMake(0, 0, width / 2, height)];
[self setupDestinationTableWithFrame:CGRectMake(width / 2, 0, width / 2, height)];
UIView* separator = [[UIView alloc] initWithFrame:CGRectMake(width / 2, 0, 1, height)];
separator.backgroundColor = [UIColor blackColor];
[self.view addSubview:separator];
[separator release];
// set up gestures
UIPanGestureRecognizer* panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanning:)];
[self.view addGestureRecognizer:panGesture];
[panGesture release];
return self;
- (void)dealloc
[srcTableNavItem release];
[dstTableNavItem release];
[srcTableView release];
[dstTableView release];
[dropArea release];
[srcData release];
[dstData release];
if(draggedCell != nil)
[draggedCell release];
if(draggedData != nil)
[draggedData release];
if(pathFromDstTable != nil)
[pathFromDstTable release];
[super dealloc];
- (void)viewWillAppear:(BOOL)animated
[srcTableView reloadData];
[dstTableView reloadData];
[UIView animateWithDuration:0.2 animations:^
CGRect frame = dstTableView.frame;
frame.size.height = kCellHeight * [dstData count];
dstTableView.frame = frame;
];
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
// Return YES for supported orientations
return UIInterfaceOrientationIsLandscape(interfaceOrientation);
#pragma mark -
#pragma mark Helper methods for initialization
- (void)setupSourceTableWithFrame:(CGRect)frame
srcTableNavItem = [[UINavigationItem alloc] init];
srcTableNavItem.title = @"Source Table";
CGRect navBarFrame = frame;
navBarFrame.size.height = kNavBarHeight;
UINavigationBar* navigationBar = [[UINavigationBar alloc] initWithFrame:navBarFrame];
[navigationBar pushNavigationItem:srcTableNavItem animated:false];
[navigationBar setTintColor:[UIColor lightGrayColor]];
[self.view addSubview:navigationBar];
[navigationBar release];
CGRect tableFrame = frame;
tableFrame.origin.y = kNavBarHeight;
tableFrame.size.height -= kNavBarHeight;
srcTableView = [[UITableView alloc] initWithFrame:tableFrame];
[srcTableView setDelegate:self];
[srcTableView setDataSource:self];
[self.view addSubview:srcTableView];
- (void)setupDestinationTableWithFrame:(CGRect)frame
dstTableNavItem = [[UINavigationItem alloc] init];
dstTableNavItem.title = @"Destination Table";
CGRect navBarFrame = frame;
navBarFrame.size.height = kNavBarHeight;
UINavigationBar* navigationBar = [[UINavigationBar alloc] initWithFrame:navBarFrame];
[navigationBar pushNavigationItem:dstTableNavItem animated:false];
[navigationBar setTintColor:[UIColor lightGrayColor]];
[self.view addSubview:navigationBar];
[navigationBar release];
CGRect dropAreaFrame = frame;
dropAreaFrame.origin.y = kNavBarHeight;
dropAreaFrame.size.height -= kNavBarHeight;
dropArea = [[UIView alloc] initWithFrame:dropAreaFrame];
[dropArea setBackgroundColor:[UIColor grayColor]];
[self.view addSubview:dropArea];
CGRect contentFrame = dropAreaFrame;
contentFrame.origin = CGPointMake(0, 0);
UILabel* dropAreaLabel = [[UILabel alloc] initWithFrame:contentFrame];
dropAreaLabel.backgroundColor = [UIColor clearColor];
dropAreaLabel.font = [UIFont boldSystemFontOfSize:12];
dropAreaLabel.textAlignment = UITextAlignmentCenter;
dropAreaLabel.textColor = [UIColor whiteColor];
dropAreaLabel.text = @"Drop items here...";
[dropArea addSubview:dropAreaLabel];
[dropAreaLabel release];
CGRect tableFrame = contentFrame;
tableFrame.size.height = kCellHeight * [dstData count];
dstTableView = [[UITableView alloc] initWithFrame:tableFrame];
[dstTableView setEditing:YES];
[dstTableView setDelegate:self];
[dstTableView setDataSource:self];
[dropArea addSubview:dstTableView];
- (void)initDraggedCellWithCell:(UITableViewCell*)cell AtPoint:(CGPoint)point
// get rid of old cell, if it wasn't disposed already
if(draggedCell != nil)
[draggedCell removeFromSuperview];
[draggedCell release];
draggedCell = nil;
CGRect frame = CGRectMake(point.x, point.y, cell.frame.size.width, cell.frame.size.height);
draggedCell = [[UITableViewCell alloc] init];
draggedCell.selectionStyle = UITableViewCellSelectionStyleGray;
draggedCell.textLabel.text = cell.textLabel.text;
draggedCell.textLabel.textColor = cell.textLabel.textColor;
draggedCell.highlighted = YES;
draggedCell.frame = frame;
draggedCell.alpha = 0.8;
[self.view addSubview:draggedCell];
#pragma mark -
#pragma mark UIGestureRecognizer
- (void)handlePanning:(UIPanGestureRecognizer *)gestureRecognizer
switch ([gestureRecognizer state])
case UIGestureRecognizerStateBegan:
[self startDragging:gestureRecognizer];
break;
case UIGestureRecognizerStateChanged:
[self doDrag:gestureRecognizer];
break;
case UIGestureRecognizerStateEnded:
case UIGestureRecognizerStateCancelled:
case UIGestureRecognizerStateFailed:
[self stopDragging:gestureRecognizer];
break;
default:
break;
#pragma mark -
#pragma mark Helper methods for dragging
- (void)startDragging:(UIPanGestureRecognizer *)gestureRecognizer
CGPoint pointInSrc = [gestureRecognizer locationInView:srcTableView];
CGPoint pointInDst = [gestureRecognizer locationInView:dstTableView];
if([srcTableView pointInside:pointInSrc withEvent:nil])
[self startDraggingFromSrcAtPoint:pointInSrc];
dragFromSource = YES;
else if([dstTableView pointInside:pointInDst withEvent:nil])
[self startDraggingFromDstAtPoint:pointInDst];
dragFromSource = NO;
- (void)startDraggingFromSrcAtPoint:(CGPoint)point
NSIndexPath* indexPath = [srcTableView indexPathForRowAtPoint:point];
UITableViewCell* cell = [srcTableView cellForRowAtIndexPath:indexPath];
if(cell != nil)
CGPoint origin = cell.frame.origin;
origin.x += srcTableView.frame.origin.x;
origin.y += srcTableView.frame.origin.y;
[self initDraggedCellWithCell:cell AtPoint:origin];
cell.highlighted = NO;
if(draggedData != nil)
[draggedData release];
draggedData = nil;
draggedData = [[srcData objectAtIndex:indexPath.row] retain];
- (void)startDraggingFromDstAtPoint:(CGPoint)point
NSIndexPath* indexPath = [dstTableView indexPathForRowAtPoint:point];
UITableViewCell* cell = [dstTableView cellForRowAtIndexPath:indexPath];
if(cell != nil)
CGPoint origin = cell.frame.origin;
origin.x += dropArea.frame.origin.x;
origin.y += dropArea.frame.origin.y;
[self initDraggedCellWithCell:cell AtPoint:origin];
cell.highlighted = NO;
if(draggedData != nil)
[draggedData release];
draggedData = nil;
draggedData = [[dstData objectAtIndex:indexPath.row] retain];
// remove old cell
[dstData removeObjectAtIndex:indexPath.row];
[dstTableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationMiddle];
pathFromDstTable = [indexPath retain];
[UIView animateWithDuration:0.2 animations:^
CGRect frame = dstTableView.frame;
frame.size.height = kCellHeight * [dstData count];
dstTableView.frame = frame;
];
- (void)doDrag:(UIPanGestureRecognizer *)gestureRecognizer
if(draggedCell != nil && draggedData != nil)
CGPoint translation = [gestureRecognizer translationInView:[draggedCell superview]];
[draggedCell setCenter:CGPointMake([draggedCell center].x + translation.x,
[draggedCell center].y + translation.y)];
[gestureRecognizer setTranslation:CGPointZero inView:[draggedCell superview]];
- (void)stopDragging:(UIPanGestureRecognizer *)gestureRecognizer
if(draggedCell != nil && draggedData != nil)
if([gestureRecognizer state] == UIGestureRecognizerStateEnded
&& [dropArea pointInside:[gestureRecognizer locationInView:dropArea] withEvent:nil])
NSIndexPath* indexPath = [dstTableView indexPathForRowAtPoint:[gestureRecognizer locationInView:dstTableView]];
if(indexPath != nil)
[dstData insertObject:draggedData atIndex:indexPath.row];
[dstTableView insertRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationMiddle];
else
[dstData addObject:draggedData];
[dstTableView reloadData];
else if(!dragFromSource && pathFromDstTable != nil)
// insert cell back where it came from
[dstData insertObject:draggedData atIndex:pathFromDstTable.row];
[dstTableView insertRowsAtIndexPaths:[NSArray arrayWithObject:pathFromDstTable] withRowAnimation:UITableViewRowAnimationMiddle];
[pathFromDstTable release];
pathFromDstTable = nil;
[UIView animateWithDuration:0.3 animations:^
CGRect frame = dstTableView.frame;
frame.size.height = kCellHeight * [dstData count];
dstTableView.frame = frame;
];
[draggedCell removeFromSuperview];
[draggedCell release];
draggedCell = nil;
[draggedData release];
draggedData = nil;
#pragma mark -
#pragma mark UITableViewDataSource
- (BOOL)tableView:(UITableView*)tableView canMoveRowAtIndexPath:(NSIndexPath*)indexPath
// disable build in reodering functionality
return NO;
- (void)tableView:(UITableView*)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
// enable cell deletion for destination table
if([tableView isEqual:dstTableView] && editingStyle == UITableViewCellEditingStyleDelete)
[dstData removeObjectAtIndex:indexPath.row];
[dstTableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
[UIView animateWithDuration:0.2 animations:^
CGRect frame = dstTableView.frame;
frame.size.height = kCellHeight * [dstData count];
dstTableView.frame = frame;
];
- (NSInteger)tableView:(UITableView*)tableView numberOfRowsInSection:(NSInteger)section
// tell our tables how many rows they will have
int count = 0;
if([tableView isEqual:srcTableView])
count = [srcData count];
else if([tableView isEqual:dstTableView])
count = [dstData count];
return count;
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
return kCellHeight;
- (UITableViewCell*)tableView:(UITableView*)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath
UITableViewCell* result = nil;
if([tableView isEqual:srcTableView])
result = [self srcTableCellForRowAtIndexPath:indexPath];
else if([tableView isEqual:dstTableView])
result = [self dstTableCellForRowAtIndexPath:indexPath];
return result;
#pragma mark -
#pragma mark Helper methods for table stuff
- (UITableViewCell*)srcTableCellForRowAtIndexPath:(NSIndexPath*)indexPath
// tell our source table what kind of cell to use and its title for the given row
UITableViewCell *cell = [srcTableView dequeueReusableCellWithIdentifier:kCellIdentifier];
if (cell == nil)
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:kCellIdentifier] autorelease];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
cell.textLabel.textColor = [UIColor darkGrayColor];
cell.textLabel.text = [[srcData objectAtIndex:indexPath.row] description];
return cell;
- (UITableViewCell*)dstTableCellForRowAtIndexPath:(NSIndexPath*)indexPath
// tell our destination table what kind of cell to use and its title for the given row
UITableViewCell *cell = [dstTableView dequeueReusableCellWithIdentifier:kCellIdentifier];
if (cell == nil)
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:kCellIdentifier] autorelease];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
cell.textLabel.textColor = [UIColor darkGrayColor];
cell.textLabel.text = [[dstData objectAtIndex:indexPath.row] description];
return cell;
@end
这是一个如何使用它的示例：
NSArray* srcData = [NSArray arrayWithObjects:@"item0", @"item1", @"item2", @"item3", @"item4", nil];
NSArray* dstData = [NSArray arrayWithObjects:@"item5", @"item6", nil];
dropTable = [[UIDropTableViewController alloc] initWithFrame:CGRectMake(100, 100, 600, 500) SourceData:srcData DestinationData:dstData];
[dropTable setSrcTableTitle:@"Bla"];
[dropTable setDstTableTitle:@"Blub"];
[[dropTable.view layer] setBorderColor:[[UIColor darkGrayColor] CGColor]];
[[dropTable.view layer] setBorderWidth:1];
[[dropTable.view layer] setCornerRadius:2];
[self.view addSubview:dropTable.view];
然后，在您完成编辑后，您只需阅读 dropTable.dstData 并继续使用它来做任何您想做的事情。
在UIDropTableViewController.m 中，您可能需要根据自己的需要调整initDraggedCellWithCell、srcTableCellForRowAtIndexPath 和dstTableCellForRowAtIndexPath，就单元格表示而言。
【讨论】：
我使用上面的代码作为我需要的基础。写得很有效率。谢谢 很好的例子。我用 Swift 重写了它并修改了它以实现双向拖动，并且效果很好。 @rmooney 你想分享你的解决方案吗？【参考方案2】：我也只需要解决一个类似的问题。这是github上编译和运行示例的链接。
https://github.com/luminixinc/UITableViewDragAndDropExample.git
享受吧。
【讨论】：
【参考方案3】：我知道这是一个非常古老的问题，但我最近在一个简单的视图助手类中实现了代码 christoph gave in his answer - 认为它可能有用：
i3-dragndrop
它支持UITableViews 和UICollectionViews 作为源和目标。
更新
我刚刚实现了上述库的第 2 版：BetweenKit。它建立在原始概念的基础上，但支持广泛的新功能，例如多目标集合、自定义渲染等等。希望对您有所帮助！
【讨论】：
【参考方案4】：您可能已经弄清楚和/或忘记了这一点，但这是为任何想知道如何做到这一点并遇到此 *** 页面的人准备的。
一个没有故事板和没有 ARC 的例子：https://github.com/josh2112/iPad-UITableView-DnD-Demo
带有故事板和 ARC 的示例：https://github.com/erikthiem/TestDragAndDropStoryboardARC
【讨论】：
【参考方案5】：上面 christoph 的代码和 Tom K 的完整功能示例项目对我来说都是说明性的。
Tom K 功能示例中的一个小点： https://github.com/luminixinc/UITableViewDragAndDropExample.git 从情节提要实例化的“UserDetailViewController”中的 IBOutlet 已损坏。
解决方法 storyboard instantiateViewControllerWithIdentifier not setting IBOutlets
【讨论】：
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