如何使用 TextField Click in iOS 显示基于先前 PickerView 的 PickerView 值？

Question

我有三个 TextField regionText sectionText distributionText。如果我单击第一个文本字段 regionText 意味着，它应该显示 PickerView regionPicker 和数组值 regionArray。如果我单击 sectionText 或 distributionText 而不选择 regionText 中的值，它应该显示警告消息。

那么，根据regionText值

ViewController.m

- (void)viewDidLoad
{
[super viewDidLoad];

//static Array for RegionPicker
NSArray *regionArray = [[NSArray alloc]initWithObjects:@"Chennai-south",@"Chennai-north",@"Villupuram", nil];

//static Array for SectionPicker
NSArray *chennaiSouthArray = [[NSArray alloc]initWithObjects:@"A",@"B",@"C", nil];
NSArray *chennaiNorthArray = [[NSArray alloc]initWithObjects:@"D",@"E",@"F", nil];
 NSArray *villupuramArray = [[NSArray alloc]initWithObjects:@"D",@"E",@"F", nil];

//static Array for DistributionPicker
NSArray *aArray = [[NSArray alloc]initWithObjects:@"a",@"b", nil];
NSArray *bArray = [[NSArray alloc]initWithObjects:@"c",@"d", nil];
NSArray *cArray = [[NSArray alloc]initWithObjects:@"e",@"f", nil];

NSArray *dArray = [[NSArray alloc]initWithObjects:@"g",@"h", nil];
NSArray *eArray = [[NSArray alloc]initWithObjects:@"i",@"j", nil];


//viewForPicker
_viewForPicker = [[UIView alloc]initWithFrame:CGRectMake(0,self.view.frame.size.height, self.view.frame.size.width,260)];
_viewForPicker.backgroundColor = [UIColor blackColor];
[self.view addSubview:_viewForPicker];

//regionPickerView
_regionPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 44, self.view.frame.size.width, 216)];
_regionPicker.delegate = self;
_regionPicker.dataSource = self;
_regionPicker.showsSelectionIndicator = YES;
[_regionPicker setBackgroundColor:[UIColor lightGrayColor]];
[_viewForPicker addSubview:_regionPicker];


//ToolBar
UIToolbar *toolBar= [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,self.view.frame.size.width,44)];
[toolBar setBarStyle:UIBarStyleBlackOpaque];
 UIBarButtonItem *barButtonDone = [[UIBarButtonItem alloc] initWithTitle:@"Done"
                                                                  style:UIBarButtonItemStyleBordered target:self action:@selector(hidePickerView:)];
toolBar.items = @[barButtonDone];
barButtonDone.tintColor=[UIColor lightTextColor];
[barButtonDone setEnabled:YES];
[_viewForPicker addSubview:toolBar];

//SettingLabels
[self setView];
}

-(void)hidePickerView:(id)sender
{

[UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
    _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height, 320, 260);
} completion:^(BOOL finished){
}];
}

-(void)setView
{

//regionLabel
UILabel *regionLabel = [[UILabel alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+30, self.view.frame.origin.y+30, 60, 25)];
[regionLabel setText:@"Region"];
[self.view addSubview:regionLabel];

//regionText
UITextField *regionText = [[UITextField alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+120, self.view.frame.origin.y+30, 150, 25)];
[regionText setBorderStyle:UITextBorderStyleRoundedRect];
[regionText setPlaceholder:@"selectRegion"];
[regionText setTag:0];
[regionText setDelegate:self];
[self.view addSubview:regionText];

//sectionLabel
UILabel *sectionLabel = [[UILabel alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+30, self.view.frame.origin.y+120, 60, 25)];
[sectionLabel setText:@"Section"];
[self.view addSubview:sectionLabel];

//sectionText
UITextField *sectionText = [[UITextField alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+120, self.view.frame.origin.y+120, 150, 25)];
[sectionText setBorderStyle:UITextBorderStyleRoundedRect];
[sectionText setPlaceholder:@"selectSection"];
[sectionText setTag:1];
[sectionText setDelegate:self];
[self.view addSubview:sectionText];


//distributionLabel
UILabel *distributionLabel = [[UILabel alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+30, self.view.frame.origin.y+210, 90, 25)];
[distributionLabel setText:@"Distribution"];
[self.view addSubview:distributionLabel];

//distributionText
UITextField *distributionText = [[UITextField alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+120, self.view.frame.origin.y+210, 150, 25)];
[distributionText setBorderStyle:UITextBorderStyleRoundedRect];
[distributionText setPlaceholder:@"selectDistribution"];
[distributionText setTag:2];
[distributionText setDelegate:self];
[self.view addSubview:distributionText];

}

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
// Show UIPickerView


if (textField isEqual:@"regionText")
{
    NSLog(@"Entering Textfield Begin");
    [UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
        _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height-260,self.view.frame.size.width, 260);
    }
                     completion:^(BOOL finished){
                     }];
}

elseif(textField isEqual:@"sectionText")
{
   //What i have to Write in This.Please Update.
}
else
{
 //What i have to Write in This.Please Update.
}
return NO;
}

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView {

return 1;
}

- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component 
{
if([pickerView isEqual:@"regionPicker"])
return [regionArray count];

elseif([pickerView isEqual:@"regionPicker"])
{
//What i have to write.Pls update.
}
else
{
//What i have to write.Pls update.
}

}

- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component 
{
//What i have to write.Pls update.
}

1.How 使用单个 UIView viewforPicker 显示 PickerView?

2.How 显示 PickerView Values Depends on previous PickerView Values?

Answer 1

将 isRangeSlected 和 fieldTag 声明为 class 范围变量并更新您的方法，如下所示。

-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
  fieldTag = textField.tag;
  // Show UIPickerView
  if(textField.tag == 0) {
    [self showPickerView];
  } else if (textField.tag == 1) {
    isRangeSlected ? [self showPickerView] : [self showAlertWithText:@"Please select range"];
  } else if (textField.tag == 2) {
    isRangeSlected ? [self showPickerView] : [self showAlertWithText:@"Please select range"];
  }
   return NO;
 }

 -(void)showPickerView {
      [UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
        _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height-260,self.view.frame.size.width, 260);
       }
      completion:^(BOOL finished){
 }];

}

    -(void)showAlertWithText:(NSString *)txt {
         [[[UIAlertView alloc] initWithTitle:@"Error" message:txt delegate:nil cancelButtonTitle:@"OK" otherButtonTitles: nil] show];
     }

将 PickerViewDataSource 方法的其余部分更新为

-(NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component
{
    if(fieldTag == 0) return [regionArray count];
    else if (fieldTag == 1) return [regionArray count];
    else return [regionArray count];
}

-(NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    //What i have to write.Pls update.
    if(fieldTag == 0) return [regionArray objectAtIndex:row];
    else if (fieldTag == 1) return [regionArray objectAtIndex:row];
    else return [regionArray objectAtIndex:row];
}

如果有任何小错误请自行更新代码，这将对您有所帮助。

Answer 2

这是经过测试的更新代码：

首先在 .h 文件中声明：

UIView *_viewForPicker;
UIPickerView *_regionPicker;
NSArray *regionArray;
NSArray *chennaiSouthArray;
NSArray *chennaiNorthArray;
NSArray *villupuramArray;
int selectionVal;

之后.m文件中：

- (void)viewDidLoad {
    [super viewDidLoad];
    self.navigationItem.leftBarButtonItem = self.editButtonItem;
    //static Array for RegionPicker
    regionArray = [[NSArray alloc] initWithObjects:@"Chennai-south",@"Chennai-north",@"Villupuram", nil];

    //static Array for SectionPicker
    chennaiSouthArray = [[NSArray alloc]initWithObjects:@"A",@"B",@"C", nil];
    chennaiNorthArray = [[NSArray alloc]initWithObjects:@"D",@"E",@"F", nil];
    villupuramArray = [[NSArray alloc]initWithObjects:@"D",@"E",@"F", nil];

    //static Array for DistributionPicker
    NSArray *aArray = [[NSArray alloc]initWithObjects:@"a",@"b", nil];
    NSArray *bArray = [[NSArray alloc]initWithObjects:@"c",@"d", nil];
    NSArray *cArray = [[NSArray alloc]initWithObjects:@"e",@"f", nil];
    NSArray *dArray = [[NSArray alloc]initWithObjects:@"g",@"h", nil];
    NSArray *eArray = [[NSArray alloc]initWithObjects:@"i",@"j", nil];


    //viewForPicker
    _viewForPicker = [[UIView alloc]initWithFrame:CGRectMake(0,self.view.frame.size.height, self.view.frame.size.width,260)];
    _viewForPicker.backgroundColor = [UIColor blackColor];
    [self.view addSubview:_viewForPicker];

    //regionPickerView
    _regionPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 44, self.view.frame.size.width, 216)];
    _regionPicker.delegate = self;
    _regionPicker.dataSource = self;
    _regionPicker.showsSelectionIndicator = YES;
    [_regionPicker setBackgroundColor:[UIColor lightGrayColor]];
    [_viewForPicker addSubview:_regionPicker];

    //ToolBar
    UIToolbar *toolBar= [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,self.view.frame.size.width,44)];
    [toolBar setBarStyle:UIBarStyleBlackOpaque];
    UIBarButtonItem *barButtonDone = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStylePlain target:self action:@selector(hidePickerView:)];
    toolBar.items = @[barButtonDone];
    barButtonDone.tintColor=[UIColor lightTextColor];
    [barButtonDone setEnabled:YES];
    [_viewForPicker addSubview:toolBar];

    //SettingLabels
    [self setView];
}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
}

-(void)hidePickerView:(id)sender {
    [UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
        _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height, 320, 260);
    } completion:^(BOOL finished){
    }];
}

-(void)setView {
    //regionLabel
    UILabel *regionLabel = [[UILabel alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+30, self.view.frame.origin.y+30, 60, 25)];
    [regionLabel setText:@"Region"];
    [self.view addSubview:regionLabel];

    //regionText
    UITextField *regionText = [[UITextField alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+120, self.view.frame.origin.y+30, 150, 25)];
    [regionText setBorderStyle:UITextBorderStyleRoundedRect];
    [regionText setPlaceholder:@"selectRegion"];
    [regionText setTag:51];
    [regionText setDelegate:self];
    [self.view addSubview:regionText];

    //sectionLabel
    UILabel *sectionLabel = [[UILabel alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+30, self.view.frame.origin.y+120, 60, 25)];
    [sectionLabel setText:@"Section"];
    [self.view addSubview:sectionLabel];

    //sectionText
    UITextField *sectionText = [[UITextField alloc] initWithFrame:CGRectMake(self.view.frame.origin.x+120, self.view.frame.origin.y+120, 150, 25)];
    [sectionText setBorderStyle:UITextBorderStyleRoundedRect];
    [sectionText setPlaceholder:@"selectSection"];
    [sectionText setTag:52];
    [sectionText setDelegate:self];
    [self.view addSubview:sectionText];

    //distributionLabel
    UILabel *distributionLabel = [[UILabel alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+30, self.view.frame.origin.y+210, 90, 25)];
    [distributionLabel setText:@"Distribution"];
    [self.view addSubview:distributionLabel];

    //distributionText
    UITextField *distributionText = [[UITextField alloc]initWithFrame:CGRectMake(self.view.frame.origin.x+120, self.view.frame.origin.y+210, 150, 25)];
    [distributionText setBorderStyle:UITextBorderStyleRoundedRect];
    [distributionText setPlaceholder:@"selectDistribution"];
    [distributionText setTag:53];
    [distributionText setDelegate:self];
    [self.view addSubview:distributionText];

}

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
    // Show UIPickerView
    if (textField.tag == 51){
        NSLog(@"Entering Textfield Begin");
        selectionVal = 1;
        [UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
            _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height-260,self.view.frame.size.width, 260);
        }completion:^(BOOL finished){}];
    }else if(textField.tag == 52){
        if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@""]) {
            [[[UIAlertView alloc] initWithTitle:@"Alert" message:@"Set Region First" delegate:self cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil] show];
        }else {
            selectionVal = 2;
            [UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
                _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height-260,self.view.frame.size.width, 260);
            }completion:^(BOOL finished){}];
        }
    }else if (textField.tag == 53){
        if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@""]) {
            [[[UIAlertView alloc] initWithTitle:@"Alert" message:@"Set Region First" delegate:self cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil] show];
        }else{
            selectionVal = 3;
            [UIView animateWithDuration:0.5 delay:0.1 options:UIViewAnimationOptionCurveEaseIn animations:^{
                _viewForPicker.frame = CGRectMake(0, self.view.frame.size.height-260,self.view.frame.size.width, 260);
            }completion:^(BOOL finished){}];
        }
    }
    [_regionPicker reloadAllComponents];
    return NO;
}

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView {
    return 1;
}

- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component{
    if(selectionVal == 1){
        return [regionArray count];
    }else if(selectionVal == 2){
        if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Chennai-south"]) {
            return chennaiSouthArray.count;
        }else if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Chennai-north"]){
            return chennaiNorthArray.count;
        }else if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Villupuram"]){
            return villupuramArray.count;
        }
    }else if(selectionVal == 3){
    }
    return 0;
}

- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component  {
    if(selectionVal == 1){
        return [regionArray objectAtIndex:row];
    }else if(selectionVal == 2){
        if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Chennai-south"]) {
            return [chennaiSouthArray objectAtIndex:row];
        }else if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Chennai-north"]){
            return [chennaiNorthArray objectAtIndex:row];
        }else if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Villupuram"]){
            return [villupuramArray objectAtIndex:row];
        }
    }
    return @"test";
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
    if(selectionVal == 1){
        [(UITextField*)[self.view viewWithTag:51] setText:[regionArray objectAtIndex:row]];
    }else if(selectionVal == 2){
        if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Chennai-south"]) {
            [(UITextField*)[self.view viewWithTag:52] setText:[chennaiSouthArray objectAtIndex:row]];
        }else if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Chennai-north"]){
            [(UITextField*)[self.view viewWithTag:52] setText:[chennaiNorthArray objectAtIndex:row]];
        }else if ([[(UITextField*)[self.view viewWithTag:51] text] isEqualToString:@"Villupuram"]){
            [(UITextField*)[self.view viewWithTag:53] setText:[villupuramArray objectAtIndex:row]];
        }

    }
}

希望对你有所帮助

如何使用 TextField Click in iOS 显示基于先前 PickerView 的 PickerView 值？

How to show PickerView Values Based on Previous PickerView Using TextField Click in iOS?

objective-c

uipickerview

uitextfield

ios