在 IOS7 中不可见 AlertView 上的选择器

Posted 2023-02-25

【中文标题】在 IOS7 中不可见 AlertView 上的选择器

【英文标题】：Picker On AlertView Not Visible in IOS7

【发布时间】：2013-10-07 12:55:21

【问题描述】：

我的以下代码在 iOS 7 以下运行良好 我正在尝试在警报中添加选择器视图，该视图在 ios7 版本以下工作正常但在 ios 7 中它显示没有选择器视图的白色警报。

    -(void)showPinPickerAlert
    
        numberarr = [[NSMutableArray alloc]initWithObjects:@"0",@"1",@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9", nil];


        UIAlertView *alert =[[UIAlertView alloc]initWithTitle:@"Enter Pin To Change Track me Option" message:@"\n\n\n\n\n\n\n" delegate:self cancelButtonTitle:@"Verify" otherButtonTitles:nil];

        UIPickerView *picker=[[UIPickerView alloc]initWithFrame:CGRectMake(25, 30, 230, 60) ];
        picker.dataSource=self;
        picker.delegate=self;
       // picker.backgroundColor=[UIColor blueColor];


        picker.showsSelectionIndicator = YES;
        //  picker.autoresizingMask = UIViewAutoresizingFlexibleHeight;
        picker.transform = CGAffineTransformMakeScale(0.6, 0.6);
        alert.tag=100;
        //  picker.transform = CGAffineTransformMakeScale(1, 0.2);
        [alert addSubview:picker];


        [alert show];

    

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView;



    return 4;





- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component


    strPin=[[NSString stringWithFormat:@"%i%i%i%i",[pickerView selectedRowInComponent:0],[pickerView selectedRowInComponent:1],[pickerView selectedRowInComponent:2],[pickerView selectedRowInComponent:3]]mutableCopy];

    NSLog(@"strPin=%@",strPin);
    // mlabel.text= [arrayNo objectAtIndex:row];





- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component;



    return [numberarr count];



**//code try to change color of picker text and background thats work fine in below ios7 but in iOS 7 still shows white screen**


- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view

    UILabel *label = (UILabel*) view;
    if (label == nil)
    
        label = [[UILabel alloc] init];
    

    //[label setText:@"Whatever"];


    // This part just colorizes everything, since you asked about that.

    [label setTextColor:[UIColor whiteColor]];
    [label setBackgroundColor:[UIColor blackColor]];
    CGSize rowSize = [pickerView rowSizeForComponent:component];
    CGRect labelRect = CGRectMake (0, 0, rowSize.width, rowSize.height);
    [label setFrame:labelRect];

    return label;



- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component;



    pickerView.backgroundColor=[UIColor blackColor];
    return [numberarr objectAtIndex:row];

输出在下面

IOS 7 中的输出

如何解决？

【问题讨论】：

找到第 3 方警报视图并使用它。您永远不应该向 UIAlertView 添加子视图 - 它从未得到官方支持。

【参考方案1】：

从 iOS7 开始，不再支持向 UIAlertView 添加子视图。

您应该实现自己的视图并尝试与警报视图类似，或者像其他人所说的那样，使用像这样的第 3 方警报视图：

https://github.com/wimagguc/ios-custom-alertview

【参考方案2】：

以下大部分代码来自 ios7 之前的堆栈溢出答案。

PickerPrompt.h

#import <UIKit/UIKit.h>

@interface PickerPrompt : UIAlertView <UIPickerViewDelegate, UIPickerViewDataSource, UITextFieldDelegate>

    UIPickerView *_pickerView;
    NSMutableArray *_options;


@property (readonly) NSString *enteredText;

- (id)initWithTitle:(NSString *)title message:(NSString *)message options:(NSMutableArray*)options delegate:(id)delegate cancelButtonTitle:(NSString *)cancelButtonTitle okButtonTitle:(NSString *)okButtonTitle;

@end

pickerPrompt.m

#import "PickerPrompt.h"

@implementation PickerPrompt
#define VIEW_TAG 49
#define SUB_LABEL_TAG 52
#define LABEL_TAG 53

#define COMPONENT_WIDTH 250
#define LABEL_WIDTH 10

@synthesize enteredText;

- (id)initWithTitle:(NSString *)title message:(NSString *)message options:(NSMutableArray*)options delegate:(id)delegate cancelButtonTitle:(NSString *)cancelButtonTitle okButtonTitle:(NSString *)okayButtonTitle


    if (self = [super initWithTitle:title message:message delegate:delegate cancelButtonTitle:cancelButtonTitle otherButtonTitles:okayButtonTitle, nil])
    
        _options = options;

        _pickerView = [[UIPickerView alloc] init];
        [_pickerView sizeToFit];
        [_pickerView setAutoresizingMask:(UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight)];
        [_pickerView setDelegate:self];
        [_pickerView setDataSource:self];
        [_pickerView setShowsSelectionIndicator:TRUE];

        // Change from pre iOS 7
        [self setAlertViewStyle:UIAlertViewStylePlainTextInput];
        [[self textFieldAtIndex:0] setDelegate:self];
        [[self textFieldAtIndex:0] setInputView:_pickerView];
        [[self textFieldAtIndex:0] becomeFirstResponder];
    
    return self;


#pragma mark -
#pragma mark Picker delegate

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView 
    return 1;


- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component 
    if (pickerView == _pickerView) 
        return [_options count];
    
    return [_options count];


- (UIView *)labelCellWithWidth:(CGFloat)width rightOffset:(CGFloat)offset 

    // Create a new view that contains a label offset from the right.
    CGRect frame = CGRectMake(0.0, 0.0, width, 32.0);
    UIView *view = [[[UIView alloc] initWithFrame:frame] autorelease];
    view.tag = VIEW_TAG;

    frame.size.width = width - offset;
    UILabel *subLabel = [[UILabel alloc] initWithFrame:frame];
    subLabel.textAlignment = UITextAlignmentRight;
    subLabel.backgroundColor = [UIColor clearColor];
    subLabel.font = [UIFont systemFontOfSize:24.0];
    subLabel.userInteractionEnabled = NO;

    subLabel.tag = SUB_LABEL_TAG;

    [view addSubview:subLabel];
    [subLabel release];
    return view;



- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string 

    NSString *fullString = [[textField text] stringByAppendingString:string];

    for (NSString* object in _options) 
        if ([object isEqualToString:fullString]) 
            return YES;
        
    

    return NO;


- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view 

    UIView *returnView = nil;

    if ((view.tag == VIEW_TAG) || (view.tag == LABEL_TAG)) 
        returnView = view;
    
    else 
        returnView = [self labelCellWithWidth:COMPONENT_WIDTH rightOffset:LABEL_WIDTH];
    

    // The text shown in the component is just the number of the component.
    NSString *text = [_options objectAtIndex:row];

    // Where to set the text in depends on what sort of view it is.
    UILabel *theLabel = nil;
    if (returnView.tag == VIEW_TAG) 
        theLabel = (UILabel *)[returnView viewWithTag:SUB_LABEL_TAG];
    
    else 
        theLabel = (UILabel *)returnView;
    

    theLabel.text = text;
    return returnView;


- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component 
    return COMPONENT_WIDTH;


- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component 
    [[self textFieldAtIndex:0] setText:[_options objectAtIndex:row]];


- (NSString *)enteredText

    return [[self textFieldAtIndex:0] text];


@end

如何使用（从警报视图委托中调用）：

PickerPrompt *prompt = [PickerPrompt alloc];

NSMutableArray *options = [[NSMutableArray alloc] initWithObjects:@"option 1", @"option 2", nil];

prompt = [prompt initWithTitle:@"Select Option" message:@"Select Option" options:options delegate:self cancelButtonTitle:@"Cancel" okButtonTitle:@"Okay"];

[prompt show];
[prompt release];