1.UITableView加載的順序是先得到表的行的高度,也就是先調用heightForRowAtIndexPath方法,然後再調用cellForRowAtIndexPath,所以我們有兩個辦法實現自定義cell高度(解決不同section的不同行高問題)。
一:改變它的加載順序,或者說白了就是計算好cell高度後,再次讓它加載heightForRowAtIndexPath方法;
二:直接在heightForRowAtIndexPath計算,做判斷,直接返回對應的高度。
以下是第一種方法的實例:
UITableView設置單元格的高度的方法
- - (CGFloat)tableView:(UITableView *)tableViewheightForRowAtIndexPath:(NSIndexPath *)indexPath {
- return 64;
- }
- // Somewhere in your header:
- NSIndexPath *selectedCellIndexPath;
- // And in the implementation file:
- - (void)tableView:(UITableView *)tableViewdidSelectRowAtIndexPath:(NSIndexPath *)indexPath {
- selectedCellIndexPath = indexPath;
- // Forces the table view to callheightForRowAtIndexPath
- [tableView reloadRowsAtIndexPaths:[NSArrayarrayWithObject:indexPath]withRowAnimation:UITableViewRowAnimationNone];
- }
- - (CGFloat)tableView:(UITableView *)tableViewheightForRowAtIndexPath:(NSIndexPath *)indexPath {
- // Note: Some operations like calling [tableViewcellForRowAtIndexPath:indexPath]
- // will call heightForRow and thus create astack overflow
- if(selectedCellIndexPath != nil
- && [selectedCellIndexPathcompare:indexPath] == NSOrderedSame)
- return 128;
- return 64;
- }
reloadRowsAtIndexPaths方法將重新調用heightForRowAtIndexPath使單元格改變高度。
reloadRowsAtIndexPaths是在3.0.存儲NSIndexPath的原因是因爲不可能在堆棧不溢出的情況下在heightForRowAtIndexPath調用類方法例如cellForRowAtIndexPath
較好的方法:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectZero];
label.tag = 1;
label.lineBreakMode = UILineBreakModeWordWrap;
label.highlightedTextColor = [UIColor whiteColor];
label.numberOfLines = 0;
label.opaque = NO; // 選中Opaque表示視圖後面的任何內容都不應該繪製
label.backgroundColor = [UIColor clearColor];
[cell.contentView addSubview:label];
[label release];
}
UILabel *label = (UILabel *)[cell viewWithTag:1];
NSString *text;
text = [textArray objectAtIndex:indexPath.row];
CGRect cellFrame = [cell frame];
cellFrame.origin = CGPointMake(0, 0);
label.text = text;
CGRect rect = CGRectInset(cellFrame, 2, 2);
label.frame = rect;
[label sizeToFit];
if (label.frame.size.height > 46) {
cellFrame.size.height = 50 + label.frame.size.height - 46;
}
else {
cellFrame.size.height = 50;
}
[cell setFrame:cellFrame];
return cell;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [self tableView:tableView cellForRowAtIndexPath:indexPath];
return cell.frame.size.height;
}