我有一个视图，我以编程方式创建了一些8个动态按钮。按钮的标题颜色为白色。我想在点击按钮时将按钮标题的颜色更改为绿色。如果我点击任何其他按钮，之前点击的按钮标题颜色应该变成白色，当前按钮标题颜色应该变成绿色。
我已经使用了下面的代码和它的工作正常更改前一个按钮的颜色，现在我想要的第一个按钮是在选择模式作为默认值，第一个按钮应该改变时，另一个按钮被点击。
- (void)viewDidLoad
{
_examsListDict1 = [[NSMutableDictionary alloc]init];
_examsListDict1[@"Exam Name"] = @"JEE Mains";
.........so on another 4 dictionaries
_examsListArray = [[NSMutableArray
alloc]initWithObjects:_examsListDict1,_examsListDict2,_examsListDict3,_examsListDict4,_examsListD
ict5, nil];
NSUInteger i;
int xCoord=0;
int yCoord=0;
int buttonWidth=120;
int buttonHeight=50;
int buffer = 1;
for (i = 0; i <[_examsListArray count]; i++)
{
aButton = [UIButton buttonWithType:UIButtonTypeCustom];
aButton.frame = CGRectMake(xCoord, yCoord,buttonWidth,buttonHeight );
[aButton setTitle:[[_examsListArray objectAtIndex:i] objectForKey:@"Exam Name"]
forState:UIControlStateNormal];
[aButton setTag:i];
[aButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[aButton setBackgroundColor:[UIColor colorWithRed:250.0f/255.0f green:255.0f/255.0f
blue:221.0f/255.0f alpha:1]];
[aButton addTarget:self action:@selector(whatever:)
forControlEvents:UIControlEventTouchUpInside];
[_buttonsHorizontalScrollView addSubview:aButton];
xCoord += buttonWidth + buffer;
}
[_buttonsHorizontalScrollView
setContentSize:CGSizeMake(aButton.frame.size.width*_examsListArray.count+203, yCoord)];
}
- (void)whatever:(id)sender
{
UIButton *tempBtn = (UIButton *)sender;
[aButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[aButton setBackgroundColor:[UIColor colorWithRed:250.0f/255.0f green:255.0f/255.0f
blue:221.0f/255.0f alpha:1]];
aButton = tempBtn;
[aButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
[aButton setBackgroundColor:[UIColor colorWithRed:133.0f/255.0f green:169.0f/255.0f
blue:83.0f/255.0f alpha:1]];
}
不，我只想让第一个按钮在加载视图时作为默认选择，每当我选择另一个按钮时，它应该改变为取消选择的颜色。
if ([aButton tag] == 0)
{
[aButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
[aButton setBackgroundColor:[UIColor colorWithRed:133.0f/255.0f green:169.0f/255.0f
blue:83.0f/255.0f alpha:1]];
}
我已经使用上面的代码来选择作为默认的第一个按钮，但是当单击其他按钮时，第一个按钮不会改变，只有当第一个按钮再次单击时，它才会改变，因为这个aButton = tempBtn。怎么做呢?
我建议您设置所有按钮的选定状态标题颜色，然后将它们添加到数组中。当你按下其中一个按钮时，只需改变它们的状态，无需处理颜色或跟踪当前选择的按钮。
@property (strong, nonatomic) NSMutableArray *yourButtons;
- (void)viewDidLoad {
[super viewDidLoad];
_examsListDict1 = [[NSMutableDictionary alloc]init];
_examsListDict1[@"Exam Name"] = @"JEE Mains";
.........so on another 4 dictionaries
_examsListArray = [[NSMutableArray alloc] initWithObjects:_examsListDict1,_examsListDict2,_examsListDict3,_examsListDict4,_examsListDict5, nil];
NSUInteger i;
int xCoord=0;
int yCoord=0;
int buttonWidth=120;
int buttonHeight=50;
int buffer = 1;
// Generate background images
//
UIImage *backgroundImage = [self imageWithColor:[UIColor colorWithRed:250.0f/255.0f green:255.0f/255.0f blue:221.0f/255.0f alpha:1]];
UIImage *selectedBackgroundImage = [self imageWithColor:[UIColor colorWithRed:133.0f/255.0f green:169.0f/255.0f blue:83.0f/255.0f alpha:1]];
// Initialize your array
//
self.yourButtons = [[NSMutableArray alloc] init];
for (i = 0; i < [_examsListArray count]; i++) {
UIButton *aButton = [UIButton buttonWithType:UIButtonTypeCustom];
aButton.frame = CGRectMake(xCoord, yCoord,buttonWidth,buttonHeight );
[aButton setTitle:[[_examsListArray objectAtIndex:i] objectForKey:@"Exam Name"] forState:UIControlStateNormal];
[aButton setTag:i];
[aButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[aButton setTitleColor:[UIColor whiteColor] forState:UIControlStateSelected];
[aButton setBackgroundImage:backgroundImage forState:UIControlStateNormal]
[aButton setBackgroundImage:selectedColorImage forState:UIControlStateSelected]
[aButton addTarget:self action:@selector(whatever:) forControlEvents:UIControlEventTouchUpInside];
[_buttonsHorizontalScrollView addSubview:aButton];
xCoord += buttonWidth + buffer;
// Select the first one
//
if (i == 0)
aButton.selected = YES;
// Add your newly created button to the array
//
[self.yourButtons addObject:aButton];
}
[_buttonsHorizontalScrollView setContentSize:CGSizeMake(aButton.frame.size.width*_examsListArray.count+203, yCoord)];
}
- (void)whatever:(id)sender {
for (UIButton *button in self.yourButtons) {
// Toggle selected flag
//
button.selected = button == sender;
}
}
+ (UIImage *)imageWithColor:(UIColor *)color {
// http://stackoverflow.com/a/24665476/1835155
//
CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [color CGColor]);
CGContextFillRect(context, rect);
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
true未按下的按钮是uicontrolstatnormal而按下的按钮是UIControlStateSelected所以根据状态设置你想要的颜色。你通常在任何人有机会使用它之前在ViewDidload中这样做-下面是一个示例设置:
button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setSelected:YES];
button.frame = CGRectMake(x, y, width, height);
[button setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
[button setTitleColor:[UIColor blueColor] forState:UIControlStateSelected];
[button setTitle:@"Button Title" forState:UIControlStateNormal];
[button addTarget:self action:@selector(buttonAction:) forControlEvents:UIControlEventTouchUpInside];
[button setBackgroundImage:[UIImage imageNamed:@"button.png"] forState:UIControlStateNormal];
[button setBackgroundImage:[UIImage imageNamed:@"buttonActive.png"] forState:UIControlStateSelected];
[button setBackgroundImage:[UIImage imageNamed:@"buttonActive.png"] forState:UIControlStateHighlighted];
[button setBackgroundImage:[UIImage imageNamed:@"buttonActive.png"] forState:UIControlStateDisabled];
我认为当触发按钮被点击时你应该做的是将状态设置为selected
- (IBAction)touchDown:(id)sender {
if (sender == trigger_button) {
[button setHighlighted:TRUE];
[button setSelected:TRUE];
}
为了在点击另一个按钮时改变第一个按钮的状态，你必须"伪造"一个触摸事件。在另一个按钮的选择器方法中这样做:
例如:-(void)thirdButtonClicked:(id) sender
{
[firstButton sendActionsForControlEvents: UIControlEventTouchUpInside];
}