Objective c UITableViewCell在自定义单元格中具有备用背景色
我希望UITableViewCells的背景每显示两个单元格就有一种不同的颜色,但当我向下和向后滚动时,它们的颜色都相同。知道我的单元格具有不同的contentView大小(根据其内容),我如何才能获得这种效果 更新: 我知道我试着按照建议在cellForRowAtIndexPath中设置它,但我得到了相同的结果:第一次向下滚动效果很好,但是再次向上滚动会弄乱单元格的背景颜色Objective c UITableViewCell在自定义单元格中具有备用背景色,objective-c,ios,cocoa-touch,uitableview,Objective C,Ios,Cocoa Touch,Uitableview,我希望UITableViewCells的背景每显示两个单元格就有一种不同的颜色,但当我向下和向后滚动时,它们的颜色都相同。知道我的单元格具有不同的contentView大小(根据其内容),我如何才能获得这种效果 更新: 我知道我试着按照建议在cellForRowAtIndexPath中设置它,但我得到了相同的结果:第一次向下滚动效果很好,但是再次向上滚动会弄乱单元格的背景颜色 - (UITableViewCell *)tableView:(UITableView *)tableView
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"CartCell";
CartCell *cell = (CartCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
Recipes *info = [_fetchedResultsController objectAtIndexPath:indexPath];
if (cell == nil)
{
cell = [[CartCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// if (!cell.nameLabel) {
// cell.nameLabel = (UILabel*)[cell viewWithTag:1];
// // cell.nameLabel = (UILabel*)[cell viewWithTag:1];
// }
// if (!cell.ingredientsLabel)
// cell.ingredientsLabel = (UILabel*)[cell viewWithTag:2];
CGSize constraint = CGSizeMake(CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), 20000.0f);
CGSize size = [info.ingredients sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];
[cell.nameLabel setFrame:CGRectMake(10, 10, CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), NAME_CELL_HEIGHT)];
[cell.ingredientsLabel setFrame:CGRectMake(CELL_CONTENT_MARGIN, CELL_CONTENT_MARGIN + NAME_CELL_HEIGHT, CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), MAX(size.height, 44.0f))];
// SETTING TEXT CONTENT
cell.nameLabel.text = info.name;
cell.ingredientsLabel.text = info.ingredients;
// SETTING BACKGROUND COLOR
// UIView *lab = [[UIView alloc] initWithFrame:cell.frame];
// [lab setBackgroundColor:[UIColor blueColor]];
if (myStore.cellBackgroundShouldBeLight == YES) {
NSLog(@"clear? %@", myStore.cellBackgroundShouldBeLight ? @"Yes" : @"No");
cell.contentView.backgroundColor = [[UIColor alloc]initWithRed:87.0/255.0 green:84.0/255.0 blue:229.0/255.0 alpha:1];
// cell.backgroundView = lab;
// ingredientsLabel.backgroundColor = [UIColor clearColor];
// nameLabel.backgroundColor = [[UIColor alloc]initWithRed:87.0/255.0 green:168.0/255.0 blue:229.0/255.0 alpha:1];
// [cell setBackgroundColor: [[UIColor alloc]initWithRed:87.0/255.0 green:168.0/255.0 blue:229.0/255.0 alpha:1]];
// [cell setBackgroundColor:[UIColor colorWithRed:.8 green:.8 blue:1 alpha:1]];
myStore.cellBackgroundShouldBeLight = NO;
} else {
// cell.contentView.tag = 2;
NSLog(@"clear? %@", myStore.cellBackgroundShouldBeLight ? @"Yes" : @"No");
cell.contentView.backgroundColor = [[UIColor alloc]initWithRed:187.0/255.0 green:184.0/255.0 blue:229.0/255.0 alpha:1];
myStore.cellBackgroundShouldBeLight = YES;
}
return cell;
}
更改单元格背景颜色的适当位置是“
cellforrowatinexpath:
”方法,在该方法中,单元格数据将被填写并返回到表视图
一种方法是:当数据进入单元格时,根据您所在的行更改背景颜色 将颜色放在cellForRowAtIndexPath上:不要设置在自定义单元格上。使用
-willDisplayCell
方法
- (void)tableView: (UITableView *)tableView willDisplayCell: (UITableViewCell *)cell forRowAtIndexPath: (NSIndexPath *)indexPath {
if (indexPath.row %2) { //change the "%2" depending on how many cells you want alternating.
UIColor *altCellColor = [UIColor colorWithRed:255/255.0 green:237/255.0 blue:227/255.0 alpha:1.0]; //this can be changed, at the moment it sets the background color to red.
cell.backgroundColor = altCellColor;
}
else if (indexPath.row %2) {
UIColor *altCellColor2 = [UIColor colorWithRed:1 green:1 blue:1 alpha:1.0]; //this can be changed, at the moment it sets the background color to white.
cell.backgroundColor = altCellColor2;
}
}
它非常简单,indexPath告诉您需要知道的一切。如果indexPath.row为偶数,则使用一种颜色。如果indexPath.row为奇数,请使用其他颜色
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
…
// SETTING BACKGROUND COLOR
// UIView *lab = [[UIView alloc] initWithFrame:cell.frame];
// [lab setBackgroundColor:[UIColor blueColor]];
if (indexPath.row % 2) {
cell.contentView.backgroundColor = [[[UIColor alloc]initWithRed:87.0/255.0 green:84.0/255.0 blue:229.0/255.0 alpha:1] autorelease];
} else {
cell.contentView.backgroundColor = [[[UIColor alloc]initWithRed:187.0/255.0 green:184.0/255.0 blue:229.0/255.0 alpha:1] autorelease];
}
…
return cell;
}
你的方法有问题,因为盲目地假设细胞将被要求交替配对是一个坏的假设。tableView可以按任意顺序请求单元格。在你的例子中,我相信细胞可以要求如下。首先,请求0、1、…、9。接下来,向下滚动并获取10、11和12。此时,0、1和2已离开屏幕。你向上滚动,要求输入2,但哦,不,你的型号是奇数交替的,所以你得到了错误的颜色。看看我用什么来定制我的表格
- (UITableViewCell *)tableView:(UITableView *)aTableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
#if USE_CUSTOM_DRAWING
const NSInteger TOP_LABEL_TAG = 1001;
const NSInteger BOTTOM_LABEL_TAG = 1002;
UILabel *topLabel;
UILabel *bottomLabel;
#endif
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [aTableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
//
// Create the cell.
//
cell =
[[[UITableViewCell alloc]
initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]
autorelease];
#if USE_CUSTOM_DRAWING
UIImage *indicatorImage = [UIImage imageNamed:@"indicator.png"];
cell.accessoryView =
[[[UIImageView alloc]
initWithImage:indicatorImage]
autorelease];
const CGFloat LABEL_HEIGHT = 20;
UIImage *image = [UIImage imageNamed:@"imageA.png"];
//
// Create the label for the top row of text
//
topLabel =
[[[UILabel alloc]
initWithFrame:
CGRectMake(
image.size.width + 2.0 * cell.indentationWidth,
0.5 * (aTableView.rowHeight - 2 * LABEL_HEIGHT),
aTableView.bounds.size.width -
image.size.width - 4.0 * cell.indentationWidth
- indicatorImage.size.width,
LABEL_HEIGHT)]
autorelease];
[cell.contentView addSubview:topLabel];
//
// Configure the properties for the text that are the same on every row
//
topLabel.tag = TOP_LABEL_TAG;
topLabel.backgroundColor = [UIColor clearColor];
topLabel.textColor = [UIColor colorWithRed:0.25 green:0.0 blue:0.0 alpha:1.0];
topLabel.highlightedTextColor = [UIColor colorWithRed:1.0 green:1.0 blue:0.9 alpha:1.0];
topLabel.font = [UIFont systemFontOfSize:[UIFont labelFontSize]];
//
// Create the label for the top row of text
//
bottomLabel =
[[[UILabel alloc]
initWithFrame:
CGRectMake(
image.size.width + 2.0 * cell.indentationWidth,
0.5 * (aTableView.rowHeight - 2 * LABEL_HEIGHT) + LABEL_HEIGHT,
aTableView.bounds.size.width -
image.size.width - 4.0 * cell.indentationWidth
- indicatorImage.size.width,
LABEL_HEIGHT)]
autorelease];
[cell.contentView addSubview:bottomLabel];
//
// Configure the properties for the text that are the same on every row
//
bottomLabel.tag = BOTTOM_LABEL_TAG;
bottomLabel.backgroundColor = [UIColor clearColor];
bottomLabel.textColor = [UIColor colorWithRed:0.25 green:0.0 blue:0.0 alpha:1.0];
bottomLabel.highlightedTextColor = [UIColor colorWithRed:1.0 green:1.0 blue:0.9 alpha:1.0];
bottomLabel.font = [UIFont systemFontOfSize:[UIFont labelFontSize] - 2];
//
// Create a background image view.
//
cell.backgroundView =
[[[UIImageView alloc] init] autorelease];
cell.selectedBackgroundView =
[[[UIImageView alloc] init] autorelease];
#endif
}
#if USE_CUSTOM_DRAWING
else
{
for (UIView *sub in [cell.contentView subviews]) {
// if([sub class] == [UITableViewCellContentView class])
NSLog(@"this is uilabel %@",[sub class]);
}
topLabel = (UILabel *)[cell viewWithTag:TOP_LABEL_TAG];
bottomLabel = (UILabel *)[cell viewWithTag:BOTTOM_LABEL_TAG];
}
topLabel.text = [NSString stringWithFormat:@"Cell at row %ld.", [indexPath row]];
bottomLabel.text = [NSString stringWithFormat:@"Some other information.", [indexPath row]];
//
// Set the background and selected background images for the text.
// Since we will round the corners at the top and bottom of sections, we
// need to conditionally choose the images based on the row index and the
// number of rows in the section.
//
UIImage *rowBackground;
UIImage *selectionBackground;
NSInteger sectionRows = [aTableView numberOfRowsInSection:[indexPath section]];
NSInteger row = [indexPath row];
if (row == 0 && row == sectionRows - 1)
{
rowBackground = [UIImage imageNamed:@"topAndBottomRow.png"];
selectionBackground = [UIImage imageNamed:@"topAndBottomRowSelected.png"];
}
else if (row == 0)
{
rowBackground = [UIImage imageNamed:@"topRow.png"];
selectionBackground = [UIImage imageNamed:@"topRowSelected.png"];
}
else if (row == sectionRows - 1)
{
rowBackground = [UIImage imageNamed:@"bottomRow.png"];
selectionBackground = [UIImage imageNamed:@"bottomRowSelected.png"];
}
else
{
rowBackground = [UIImage imageNamed:@"middleRow.png"];
selectionBackground = [UIImage imageNamed:@"middleRowSelected.png"];
}
((UIImageView *)cell.backgroundView).image = rowBackground;
((UIImageView *)cell.selectedBackgroundView).image = selectionBackground;
// cell.backgroundView.backgroundColor = [UIColor colorWithPatternImage:rowBackground];
// cell.selectedBackgroundView.backgroundColor = [UIColor colorWithPatternImage:selectionBackground];
//
// Here I set an image based on the row. This is just to have something
// colorful to show on each row.
//
if ((row % 3) == 0)
{
cell.imageView.image = [UIImage imageNamed:@"imageA.png"];
}
else if ((row % 3) == 1)
{
cell.imageView.image = [UIImage imageNamed:@"imageB.png"];
}
else
{
cell.imageView.image = [UIImage imageNamed:@"imageC.png"];
}
#else
cell.text = [NSString stringWithFormat:@"Cell at row %ld.", [indexPath row]];
#endif
return cell;
}
在所有#导入
行之后通过它
#define USE_CUSTOM_DRAWING 1
标题##更改其他颜色的最简单方法
这将导致相当大的泄漏。@max_u如果他使用的是ARC,则不会,但我将添加自动释放。@jeffery_uThomas,
UIColor
有一个自动释放方法,您应该改用它<代码>[UIColor COLOR WITHRED…]@max_uu是的,我知道,就我个人而言,我从不使用alloc/init来表示颜色,但这不是原始海报所使用的。我尽量坚持使用原始代码。我希望人们只看到所需的更改。此外-您可能必须执行cell.textlab.backgroundColor=[UIColor clearColor]才能看到bg颜色。
#define USE_CUSTOM_DRAWING 1
if(indexPath.row%2) {
cell.backgroundColor=[UIColor nameUrColor] //brownColor, yellowColor, blueColor
} else {
cell.backgroundColor=[UIColor nameAnotherColor]
}
if(cell.contentView)
{
[cell.nameLbl setFont:[UIFont systemFontOfSize:24]];
int red_value = arc4random() % 210;
int green_value = arc4random() % 210;
int blue_value = arc4random() % 210;
cell.contentView.backgroundColor = [UIColor colorWithRed:red_value/255.0 green:green_value/255.0 blue:blue_value/255.0 alpha:0.6];
}