ios学习--iphone 实现下拉菜单

http://blog.163.com/ytrtfhj@126/blog/static/8905310920116224445195/

 

通过网上资料，自己借助资料写的代码，这是完全代码

//****************************************************************************

@interface DropDown1 : UIView <UITableViewDelegate,UITableViewDataSource> {

    UITableView *tv;//下拉列表

    NSArray *tableArray;//下拉列表数据

    UITextField *textField;//文本输入框

    BOOL showList;//是否弹出下拉列表

    CGFloat tabheight;//table下拉列表的高度

    CGFloat frameHeight;//frame的高度

}

 

@property (nonatomic,retain) UITableView *tv;

@property (nonatomic,retain) NSArray *tableArray;

@property (nonatomic,retain) UITextField *textField;

 

@end

 

//****************************************************************************

 

@implementation DropDown1

 

@synthesize tv,tableArray,textField;

 

- (void)dealloc

{

    [tv release];

    [tableArrayrelease];

    [textFieldrelease];

    [super dealloc];

}

 

-(id)initWithFrame:(CGRect)frame

{

    if (frame.size.height<200) {

        frameHeight = 200;

    }else{

        frameHeight = frame.size.height;

    }

    tabheight = frameHeight-30;

    

    frame.size.height = 30.0f;

    

    self=[super initWithFrame:frame];

 

    if(self){

        showList = NO; //默认不显示下拉框

        

        tv = [[UITableView alloc] initWithFrame:CGRectMake(0, 30, frame.size.width, 0)]; 

        tv.delegate = self;

        tv.dataSource = self;  

        tv.backgroundColor = [UIColorgrayColor];  

        tv.separatorColor = [UIColorlightGrayColor];  

        tv.hidden = YES;  

        [self addSubview:tv];  

 

        textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, frame.size.width, 30)];

        textField.borderStyle=UITextBorderStyleRoundedRect;//设置文本框的边框风格

        [textFieldaddTarget:selfaction:@selector(dropdown) forControlEvents:UIControlEventAllTouchEvents];

        [self addSubview:textField];

        

    }

    returnself;

}

-(void)dropdown{

    [textFieldresignFirstResponder];

    if (showList) {//如果下拉框已显示，什么都不做

        return;

    }else {//如果下拉框尚未显示，则进行显示

        

        CGRect sf = self.frame;

        sf.size.height = frameHeight;

        

        //把dropdownList放到前面，防止下拉框被别的控件遮住

        [self.superviewbringSubviewToFront:self];

        tv.hidden = NO;

        showList = YES;//显示下拉框

        

        CGRect frame = tv.frame;

        frame.size.height = 0;

        tv.frame = frame;

        frame.size.height = tabheight;

        [UIViewbeginAnimations:@"ResizeForKeyBoard"context:nil]; 

        [UIViewsetAnimationCurve:UIViewAnimationCurveLinear];  

        self.frame = sf;

        tv.frame = frame;

        [UIViewcommitAnimations];

    }

}

 

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

{

    return 1;

}

 

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section

{

    return [tableArraycount];

}

 

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

{

    static NSString *CellIdentifier = @"Cell";

    

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) {

        cell = [[[UITableViewCellalloc] initWithStyle:UITableViewCellStyleDefaultreuseIdentifier:CellIdentifier] autorelease];

    }

    

    cell.textLabel.text = [tableArray objectAtIndex:[indexPath row]];

    cell.textLabel.font = [UIFontsystemFontOfSize:16.0f];

    cell.accessoryType = UITableViewCellAccessoryNone;

    cell.selectionStyle = UITableViewCellSelectionStyleGray;

    

    return cell;

}

-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath

{

    return 35;

}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath

{

    textField.text = [tableArray objectAtIndex:[indexPath row]];

    showList = NO;

    tv.hidden = YES;

    

    CGRect sf = self.frame;
    sf.size.height = 30;
    self.frame = sf;

    CGRect frame = tv.frame;
    frame.size.height = 0;
    tv.frame = frame;

}

 

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation

{

    // Return YES for supported orientations

    return (interfaceOrientation == UIInterfaceOrientationPortrait);

}

 

@end

 

//****************************************************************************

上面的是实现方法，下面是使用：

 

 DropDown1 *dd1 = [[DropDown1alloc] initWithFrame:CGRectMake(10, 10, 140, 100)];

 dd1.textField.placeholder = @"请输入联系方式";

 NSArray* arr=[[NSArrayalloc]initWithObjects:@"电话",@"email",@"手机",@"aaa",@"bbb",@"ccc",nil];

 dd1.tableArray = arr;

 [arr release];

 [self.view addSubview:dd1];

 [dd1 release];