iOS 中单选按钮的使用[可以按步骤复制代码先看效果]
一、创建一个单选按钮的类
#import <UIKit/UIKit.h>
@protocol RadioButtonDelegate
-(void)radioButtonSelectedAtIndex:(NSUInteger)index inGroup:(NSString*)groupId;
@end
@interface RadioButton : UIView {
NSString *_groupId;
NSUInteger _index;
UIButton *_button;
}
@property(nonatomic,retain)NSString *groupId;
@property(nonatomic,assign)NSUInteger index;
-(id)initWithGroupId:(NSString*)groupId index:(NSUInteger)index;
+(void)addObserverForGroupId:(NSString*)groupId observer:(id)observer;
// 可以设置默认选中项
- (void) setChecked:(BOOL)isChecked;
@end
二、。m实现文件
#import "RadioButton.h"
@interface RadioButton()
-(void)defaultInit;
-(void)otherButtonSelected:(id)sender;
-(void)handleButtonTap:(id)sender;
@end
@implementation RadioButton
@synthesize groupId=_groupId;
@synthesize index=_index;
static const NSUInteger kRadioButtonWidth=22;
static const NSUInteger kRadioButtonHeight=22;
static NSMutableArray *rb_instances=nil;
static NSMutableDictionary *rb_instancesDic=nil; // 识别不同的组
static NSMutableDictionary *rb_observers=nil;
#pragma mark - Observer
+(void)addObserverForGroupId:(NSString*)groupId observer:(id)observer{
if(!rb_observers){
rb_observers = [[NSMutableDictionary alloc] init];
}
if ([groupId length] > 0 && observer) {
[rb_observers setObject:observer forKey:groupId];
// Make it weak reference
[observer release];
}
}
#pragma mark - Manage Instances
+(void)registerInstance:(RadioButton*)radioButton withGroupID:(NSString *)aGroupID{
if(!rb_instancesDic){
rb_instancesDic = [[NSMutableDictionary alloc] initWithCapacity:16];
}
if ([rb_instancesDic objectForKey:aGroupID]) {
[[rb_instancesDic objectForKey:aGroupID] addObject:radioButton];
[rb_instancesDic setObject:[rb_instancesDic objectForKey:aGroupID] forKey:aGroupID];
[radioButton release];
}else {
NSMutableArray *arr = [[NSMutableArray alloc] initWithCapacity:16];
[arr addObject:radioButton];
[radioButton release];
[rb_instancesDic setObject:arr forKey:aGroupID];
}
}
#pragma mark - Class level handler
+(void)buttonSelected:(RadioButton*)radioButton{
// Notify observers
if (rb_observers) {
id observer= [rb_observers objectForKey:radioButton.groupId];
if(observer && [observer respondsToSelector:@selector(radioButtonSelectedAtIndex:inGroup:)]){
[observer radioButtonSelectedAtIndex:radioButton.index inGroup:radioButton.groupId];
}
}
// Unselect the other radio buttons
// 初始化按钮数组
rb_instances = [rb_instancesDic objectForKey:radioButton.groupId];
if (rb_instances) {
for (int i = 0; i < [rb_instances count]; i++) {
RadioButton *button = [rb_instances objectAtIndex:i];
if (![button isEqual:radioButton]) {
[button otherButtonSelected:radioButton];
}
}
}
}
#pragma mark - Object Lifecycle
-(id)initWithGroupId:(NSString*)groupId index:(NSUInteger)index{
self = [self init];
if (self) {
_groupId = groupId;
_index = index;
[self defaultInit]; // 移动至此
}
return self;
}
- (id)init{
self = [super init];
if (self) {
// [self defaultInit];
}
return self;
}
- (void)dealloc
{
[_groupId release];
[_button release];
[super dealloc];
}
#pragma mark - Set Default Checked
- (void) setChecked:(BOOL)isChecked
{
if (isChecked) {
[_button setSelected:YES];
}else {
[_button setSelected:NO];
}
}
#pragma mark - Tap handling
-(void)handleButtonTap:(id)sender{
[_button setSelected:YES];
[RadioButton buttonSelected:self];
}
-(void)otherButtonSelected:(id)sender{
// Called when other radio button instance got selected
if(_button.selected){
[_button setSelected:NO];
}
}
#pragma mark - RadioButton init
-(void)defaultInit{
// Setup container view
self.frame = CGRectMake(0, 0, kRadioButtonWidth, kRadioButtonHeight);
// Customize UIButton
_button = [UIButton buttonWithType:UIButtonTypeCustom];
_button.frame = CGRectMake(0, 0,kRadioButtonWidth, kRadioButtonHeight);
_button.adjustsImageWhenHighlighted = NO;
[_button setImage:[UIImage imageNamed:@"RadioButton-Unselected"] forState:UIControlStateNormal];
[_button setImage:[UIImage imageNamed:@"RadioButton-Selected"] forState:UIControlStateSelected];
[_button addTarget:self action:@selector(handleButtonTap:) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:_button];
// [RadioButton registerInstance:self];
// update follow:
[RadioButton registerInstance:self withGroupID:self.groupId];
}
@end
三、使用
在控制器的。m文件中
#import "RadioButton.h"
@interface RadioButtonViewController()<RadioButtonDelegate>
@property (nonatomic,retain) NSMutableDictionary *dic;
@end
@implementation RadioButtonViewController
@synthesize dic=_dic;
- (void)viewDidLoad
{
[super viewDidLoad];
UIView *container = [[UIView alloc] initWithFrame:CGRectMake(10, 20, 300, 400)];
container.backgroundColor = [UIColor lightGrayColor];
[self.view addSubview:container];
UILabel *questionText = [[UILabel alloc] initWithFrame:CGRectMake(0,0,280,20)];
questionText.backgroundColor = [UIColor clearColor];
questionText.text = @"1. Which color do you like?";
[container addSubview:questionText];
RadioButton *rb1 = [[RadioButton alloc] initWithGroupId:@"first group" index:0];
RadioButton *rb2 = [[RadioButton alloc] initWithGroupId:@"first group" index:1];
RadioButton *rb3 = [[RadioButton alloc] initWithGroupId:@"first group" index:2];
rb1.frame = CGRectMake(10,30,22,22);
rb2.frame = CGRectMake(10,60,22,22);
rb3.frame = CGRectMake(10,90,22,22);
[container addSubview:rb1];
[container addSubview:rb2];
[container addSubview:rb3];
UILabel *label1 =[[UILabel alloc] initWithFrame:CGRectMake(40, 30, 60, 20)];
label1.backgroundColor = [UIColor clearColor];
label1.text = @"Red";
[container addSubview:label1];
UILabel *label2 =[[UILabel alloc] initWithFrame:CGRectMake(40, 60, 60, 20)];
label2.backgroundColor = [UIColor clearColor];
label2.text = @"Green";
[container addSubview:label2];
UILabel *label3 =[[UILabel alloc] initWithFrame:CGRectMake(40, 90, 60, 20)];
label3.backgroundColor = [UIColor clearColor];
label3.text = @"Blue";
[container addSubview:label3];
// idebug 增加
UILabel *questionText2 = [[UILabel alloc] initWithFrame:CGRectMake(0,130,300,20)];
questionText2.backgroundColor = [UIColor clearColor];
[questionText2 setAdjustsFontSizeToFitWidth:YES];
questionText2.text = @"2. Diaoyu islands belong to which country?";
[container addSubview:questionText2];
RadioButton *rb11 = [[RadioButton alloc] initWithGroupId:@"second group" index:0];
RadioButton *rb12 = [[RadioButton alloc] initWithGroupId:@"second group" index:1];
RadioButton *rb13 = [[RadioButton alloc] initWithGroupId:@"second group" index:2];
rb11.frame = CGRectMake(10,160,22,22);
rb12.frame = CGRectMake(10,190,22,22);
rb13.frame = CGRectMake(10,220,22,22);
// 设置一个默认选项
[rb11 setChecked:YES];
[container addSubview:rb11];
[container addSubview:rb12];
[container addSubview:rb13];
UILabel *label11 =[[UILabel alloc] initWithFrame:CGRectMake(40, 160, 60, 20)];
label11.backgroundColor = [UIColor clearColor];
label11.text = @"China";
[container addSubview:label11];
UILabel *label22 =[[UILabel alloc] initWithFrame:CGRectMake(40, 190, 60, 20)];
label22.backgroundColor = [UIColor clearColor];
label22.text = @"China";
[container addSubview:label22];
UILabel *label33 =[[UILabel alloc] initWithFrame:CGRectMake(40, 220, 60, 20)];
label33.backgroundColor = [UIColor clearColor];
label33.text = @"China";
[container addSubview:label33];
[RadioButton addObserverForGroupId:@"first group" observer:self];
[RadioButton addObserverForGroupId:@"second group" observer:self];
UIButton *submitBtn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
submitBtn.frame = CGRectMake(40, 280, 300-60, 40);
[submitBtn setTitle:@"提交答案" forState:UIControlStateNormal];
[submitBtn addTarget:self action:@selector(submitClick:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:submitBtn];
_dic = [[NSMutableDictionary alloc] initWithCapacity:16];
}
-(void)submitClick:(id)sender
{
NSLog(@"dic=%@",self.dic);
UILabel *resultLbl =[[UILabel alloc] initWithFrame:CGRectMake(40, 340, 240, 30)];
resultLbl.backgroundColor = [UIColor whiteColor];
resultLbl.textColor = [UIColor redColor];
NSMutableString *resultStr = [[NSMutableString alloc] initWithCapacity:16];
for (NSString *str in [self.dic allValues]) {
[resultStr appendFormat:@" %@,",str];
}
resultLbl.text = resultStr;
[self.view addSubview:resultLbl];
}
-(void)radioButtonSelectedAtIndex:(NSUInteger)index inGroup:(NSString *)groupId{
NSLog(@"changed to %d in %@",index,groupId);
[_dic setObject:[NSString stringWithFormat:@"%d",index+1] forKey:groupId];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
