xcode 如何在同一个视图中编写多个 UIPickerView？
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How can I program more than one UIPickerView in the same View?
提问by user1450221
I am using textFields inputView property to display UIPickerViews instead of the keyboard. The way I have it programmed, I do not declare the PickerViews in the .H file, or connect them in the view in interface builder. When I implement the properties of the pickerviews, I am not able to make each of them with different properties. I tried using "if" statements to tell it to have different properties depending on which picker was being used like follows....
我使用 textFields inputView 属性来显示 UIPickerViews 而不是键盘。按照我的编程方式，我没有在 .H 文件中声明 PickerViews，也没有在界面构建器的视图中连接它们。当我实现选择器视图的属性时，我无法使它们中的每一个都具有不同的属性。我尝试使用“if”语句告诉它根据使用的选择器具有不同的属性，如下所示......
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)agePickerView {
if ([pickerView isEqual: agePickerView]){
return 1;
}
if ([pickerView isEqual: weightPickerView]){
return 1;
}
}
}
When I do this though, It will say that weightPickerView is undeclared. So here is my code for implementing the pickerViews.
但是，当我这样做时，它会说 weightPickerView 未声明。所以这是我实现pickerViews的代码。
@implementation MainViewController
//WEIGHT FIELD CODE
-(IBAction)weightFieldDidBeginEditing{
UIPickerView *weightPickerView = [[UIPickerView alloc] init];
weightField.inputView = weightPickerView;
weightPickerView.showsSelectionIndicator = YES;
weightPickerView.delegate = self;
weightPickerView.dataSource = self;
[weightPickerView release];
UIToolbar *weightToolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,320,44)];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(pickerDoneClicked:)];
[weightToolBar setItems:[NSArray arrayWithObject:doneButton] animated:NO];
weightField.inputAccessoryView = weightToolBar;
}
-(NSInteger)weightpickerView:(UIPickerView *)weightPickerView numberOfRowsInComponent: (NSInteger)component{
return [weightPickerArray count];
}
-(NSString *)weightpickerView:(UIPickerView*)weightPickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [weightPickerArray objectAtIndex:row];
}
// AGE FIELD CODE
-(IBAction)ageFieldDidBeginEditing{
UIPickerView *agePickerView = [[UIPickerView alloc] init];
ageField.inputView = agePickerView;
agePickerView.showsSelectionIndicator = YES;
agePickerView.delegate = self;
agePickerView.dataSource = self;
[agePickerView release];
UIToolbar *ageToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,320,44)];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(pickerDoneClicked:)];
[ageToolbar setItems:[NSArray arrayWithObject:doneButton] animated:NO];
ageField.inputAccessoryView = ageToolbar;
}
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)agePickerView {
return 1;
}
-(NSInteger)pickerView:(UIPickerView *)agePickerView numberOfRowsInComponent: (NSInteger)component {
return [agePickerArray count];
}
-(NSString *)pickerView:(UIPickerView*)agePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [agePickerArray objectAtIndex:row];
}
-(void)pickerView:(UIPickerView *)agePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
ageField.text = (NSString *) [agePickerArray objectAtIndex:row];
}
-(void)pickerDoneClicked:(id)sender{
[ageField resignFirstResponder];
[weightField resignFirstResponder];
}
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
[super viewDidLoad];
agePickerArray = [[NSMutableArray alloc] init];
for (int age=1; age<=100; age++) {
NSString *ageString = [NSString stringWithFormat:@"%d%",age];
[agePickerArray addObject:ageString];
weightPickerArray = [[NSMutableArray alloc] init];
for (int weight = 50; weight<=500; weight++) {
NSString *weightString = [NSString stringWithFormat:@"%d%",weight];
[weightPickerArray addObject:weightString];
}
}
Is there any other way to do what I am trying to do , because that way is not working... And if i just try and redo the implementation for each picker view i get the errors of "redefinition of...""numberOfRowsInComponent"" or which ever other property i am doing. Please help, even if I have to change it and declare the pickerViews in the .H file somehow, I don't care what I have to do as long as I can get this to work!!
有没有其他方法可以做我想做的事情，因为这种方法行不通......如果我只是尝试为每个选择器视图重做实现，我会收到“重新定义......”的错误消息“numberOfRowsInComponent” "" 或我正在做的其他任何属性。请帮忙，即使我必须更改它并以某种方式在 .H 文件中声明 pickerViews，我不在乎我必须做什么，只要我能做到这一点工作！！
THANKS
谢谢
UPDATE!!!
更新！！！
@interface MainViewController : UIViewController <FlipsideViewControllerDelegate,UITextFieldDelegate,UIPickerViewDelegate,UIPickerViewDataSource> {
IBOutlet UITextField*ageField;
NSMutableArray *agePickerArray;
IBOutlet UITextField*weightField;
NSMutableArray *weightPickerArray;
UIPickerView *weightPickerView;
UIPickerView *agePickerView;
}
- (IBAction)ageFieldDidBeginEditing;
- (IBAction)weightFieldDidBeginEditing;
- (IBAction)showInfo:(id)sender;
- (IBAction)activityButtonClicked;
@end
.m file
.m 文件
-(IBAction)weightFieldDidBeginEditing{
//UIPickerView *weightPickerView = [[UIPickerView alloc] init];
weightField.inputView = weightPickerView;
weightPickerView.showsSelectionIndicator = YES;
weightPickerView.delegate = self;
weightPickerView.dataSource = self;
[weightPickerView release];
UIToolbar *weightToolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,320,44)];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(pickerDoneClicked:)];
[weightToolBar setItems:[NSArray arrayWithObject:doneButton] animated:NO];
weightField.inputAccessoryView = weightToolBar;
}
-(NSInteger)weightpickerView:(UIPickerView *)weightPickerView numberOfRowsInComponent:(NSInteger)component{
return [weightPickerArray count];
}
-(NSString *)weightpickerView:(UIPickerView*)weightPickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [weightPickerArray objectAtIndex:row];
}
// AGE FIELD CODE
// 年龄字段代码
-(IBAction)ageFieldDidBeginEditing{
//UIPickerView *agePickerView = [[UIPickerView alloc] init];
ageField.inputView = agePickerView;
agePickerView.showsSelectionIndicator = YES;
agePickerView.delegate = self;
agePickerView.dataSource = self;
[agePickerView release];
UIToolbar *ageToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,320,44)];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(pickerDoneClicked:)];
[ageToolbar setItems:[NSArray arrayWithObject:doneButton] animated:NO];
ageField.inputAccessoryView = ageToolbar;
}
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)agePickerView {
return 1;
}
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
if ([pickerView isEqual: agePickerView]) {
return [agePickerArray count];
}
if ([pickerView isEqual:weightPickerView]) {
return [weightPickerArray count];
}
}
-(NSString *)pickerView:(UIPickerView*)agePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [agePickerArray objectAtIndex:row];
}
-(void)pickerView:(UIPickerView *)agePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
ageField.text = (NSString *) [agePickerArray objectAtIndex:row];
}
-(void)pickerDoneClicked:(id)sender{
[ageField resignFirstResponder];
[weightField resignFirstResponder];
}
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
[super viewDidLoad];
agePickerArray = [[NSMutableArray alloc] init];
for (int age=1; age<=100; age++) {
NSString *ageString = [NSString stringWithFormat:@"%d%",age];
[agePickerArray addObject:ageString];
weightPickerArray = [[NSMutableArray alloc] init];
for (int weight = 50; weight<=500; weight++) {
NSString *weightString = [NSString stringWithFormat:@"%d%",weight];
[weightPickerArray addObject:weightString];
}
}
回答by ohr
UIPickerView *weightPickerView = [[UIPickerView alloc] init];
You need to declare that in your .h file (or interface).
您需要在 .h 文件（或界面）中声明。
Are you subclassing UIPickerView?
你是子类化UIPickerView吗？
Edit* If you don't want to declare those in your .h file for some reason, set a tagto your pickers.
编辑* 如果您出于某种原因不想在 .h 文件中声明它们，请将 a 设置tag为您的选择器。
All of your UIPickerViews will be calling UIPickerViewDelegate methods, meaning -(NSInteger)weightpickerView:(UIPickerView *)weightPickerView numberOfRowsInComponent: (NSInteger)componentwill not be called unless you are subclassing and creating your own methods (which I believe you are not), i.e.
您所有的UIPickerViews 都将调用 UIPickerViewDelegate 方法，这意味着-(NSInteger)weightpickerView:(UIPickerView *)weightPickerView numberOfRowsInComponent: (NSInteger)component除非您子类化并创建自己的方法（我相信您不是），否则不会被调用，即
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent: (NSInteger)component {
if([pickerView isEqual: agePickerView]){
return [agePickerArray count];
}else if([pickerView isEqual: weightPickerView]){
return [weightPickerArray count];
}else return 0;
}
If you'd like to do it with tags;
如果你想用标签来做；
weightPickerView.tag = 100; //set the tag
if(pickerView.tag == 100) //check which picker it is
回答by Vinodh
set tag to each picker view and handle them differently based on tag
为每个选择器视图设置标签并根据标签进行不同的处理
