当我的用户在表格视图中搜索某些内容时，如果没有返回任何结果，则我的应用程序会在表格视图中显示标准的“无结果”占位符。就是说，当没有结果存在时，我想返回一个填充的单元格（使用默认数据填充的单元格）。我该怎么做？我尝试了以下操作，但仍返回“无结果”？
ViewController.m
- (NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (tableView == self.searchDisplayController.searchResultsTableView) {
if ([searchResults count] == 0) {
return 1;
}
else {
return [searchResults count];
}
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *NetworkTableIdentifier = @"sidebarCell";
self.sidetableView.separatorStyle = UITableViewCellSeparatorStyleNone;
sidebarCell *cell = (sidebarCell *)[tableView dequeueReusableCellWithIdentifier:NetworkTableIdentifier];
if (cell == nil)
{
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"sidebarCell" owner:self options:nil];
cell = [nib objectAtIndex:0];
}
if (tableView == self.searchDisplayController.searchResultsTableView) {
NSDictionary *userName = [searchResults objectAtIndex:indexPath.row];
NSString *first = [userName objectForKey:@"first name"];
NSString *last = [userName objectForKey:@"last name"];
[[cell username] setText:[NSString stringWithFormat:@"%@ %@", first, last]];
NSDictionary *userlast = [searchResults objectAtIndex:indexPath.row];
[[cell lastName] setText:[userlast objectForKey:@"last name"]];
NSDictionary *userBio = [searchResults objectAtIndex:indexPath.row];
[[cell userDescription] setText:[userBio objectForKey:@"userbio"]];
NSString *area = [userName objectForKey:@"neighbourhood"];
NSString *city = [userName objectForKey:@"city"];
[[cell areaLabel] setText:[NSString stringWithFormat:@"%@, %@", area, city]];
NSString *profilePath = [[searchResults objectAtIndex:indexPath.row] objectForKey:@"photo_path"];
[cell.usermini sd_setImageWithURL:[NSURL URLWithString:profilePath]];
if ([searchResults count] == 0) {
NSLog(@"SEARCH RESULTS ARE %@", searchResults);
[[cell username] setText:[NSString stringWithFormat:@"%@", self.searchBar.text]];
[[cell lastName] setText:[userlast objectForKey:@""]];
[[cell userDescription] setText:@"This friend is not on the app (yet!) Tap to invite them."];
[[cell areaLabel] setText:[NSString stringWithFormat:@""]];
NSString *profileDefault = @"http://url.com/user.png";
[cell.usermini sd_setImageWithURL:[NSURL URLWithString:profileDefault]];
return cell;
}
return cell;
}
答案 0 :(得分：0)
我不建议您这样做，因为如果没有搜索结果，您应该返回一个空列表。这与用户界面准则一致。但是，如果您坚持要求，则可以创建一个默认对象，并使用该对象初始化searchResults数组，并从numberOfRows方法返回1。像这样：
- (NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (tableView == self.searchDisplayController.searchResultsTableView) {
if ([searchResults count] == 0) {
NSDictionary *dict = [NSDictionary dictionaryWithObjects:@[@“Enter First Name”, @“Enter Last Name”, @“Enter User Bio”, @“Enter Neighborhood”, @“Enter City”, @“Enter Photo Path”]
forKeys: @[@“first_name”, @“last_name, @“userbio”, @“neighbourhood”, @“city”, @“photo_path”];
searchResults = [NSArray arrayWithObjects: dict, nil];
return 1;
}
else {
return [searchResults count];
}
}
而且，您可以如下所示大大简化cellForRowAtIndexPath代码：
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *NetworkTableIdentifier = @"sidebarCell";
self.sidetableView.separatorStyle = UITableViewCellSeparatorStyleNone;
sidebarCell *cell = (sidebarCell *)[tableView dequeueReusableCellWithIdentifier:NetworkTableIdentifier];
if (cell == nil)
{
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"sidebarCell" owner:self options:nil];
cell = [nib objectAtIndex:0];
}
if (tableView == self.searchDisplayController.searchResultsTableView) {
//Note, I like to name my local variables the same as the dictionary keys just to eliminate any confusion
NSDictionary *userObject = [searchResults objectAtIndex:indexPath.row];
NSString *first_name = [userObject objectForKey:@"first name"];
NSString *last_name = [userObject objectForKey:@"last name"];
NSString *userbio = [userObject objectForKey:@“userbio”];
NSString *neighbourhood = [userObject objectForKey:@“neighbourhood”];
NSString *city = [userObject objectForKey:@“city”];
NSString *photo_path = [userObject objectForKey:@“photo_path”];
[[cell username] setText:[NSString stringWithFormat:@"%@ %@", first_name, last_name]];
[[cell lastName] setText:last_name];
[[cell userDescription] setText:userbio];
[[cell areaLabel] setText:[NSString stringWithFormat:@"%@, %@", neighbourhood, city]];
[[cell usermini] sd_setImageWithURL:[NSURL URLWithString:photo_path]];
}
return cell;
}
答案 1 :(得分：0)
我在应用中做了类似的事情。这很丑陋，我不建议您采用这种方式。我之所以这样做，是因为我有点懒于布局，并将占位符放在视图层次结构中的正确位置并处理所有这些隐藏/显示情况。我的视图控制器的视图层次结构非常复杂，而表视图正是我所需要的（视图或工具栏显示时自动调整大小）。
我建议您在搜索结果为空时隐藏表格视图，并用占位符代替。
答案 2 :(得分：0)
尝试一下，它会起作用：
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
NSInteger numOfSections = 0;
if (arrData.count>0)
{
self.TblView.separatorStyle = UITableViewCellSeparatorStyleSingleLine;
numOfSections = 1;
self.TblView.backgroundView = nil;
}
else
{
UILabel *noDataLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, self.TblView.bounds.size.width, self.TblView.bounds.size.height)];
noDataLabel.text = @"No Results";
noDataLabel.textColor = [UIColor blackColor];
noDataLabel.textAlignment = NSTextAlignmentCenter;
self.TblView.backgroundView = noDataLabel;
self.TblView.separatorStyle = UITableViewCellSeparatorStyleNone;
}
return numOfSections;
}