带有完成按钮的 UIPickerView 不起作用

Posted 2023-02-24

【中文标题】带有完成按钮的 UIPickerView 不起作用

【英文标题】：UIPickerView with done button not working

【发布时间】：2014-12-01 18:48:38

【问题描述】：

带有工具栏的选取器视图，在其上创建了完成按钮。单击完成按钮后它不起作用。

选择器视图向上滚动。点击完成按钮。

-(void)createPicker:(id)sender

    pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0,100,0,0)];
    [pickerView setDataSource: self];
    [pickerView setDelegate: self];
    pickerView.showsSelectionIndicator = YES;
    [pickerView setBackgroundColor:[UIColor whiteColor]];

    UIToolbar *toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 44)];
    toolBar.barStyle = UIBarStyleBlackOpaque;
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doneTouched:)];
    [toolBar setItems:[NSArray arrayWithObjects:[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil], doneButton, nil]];
    [pickerView addSubview:toolBar];

点击完成按钮关闭pickerView

-(void)doneTouched:(id)sender
     [pickerview removeFromSuperview];
 

我不知道我在这里做错了什么。谁能建议我如何调用添加在 uipickerview 工具栏按钮上的完成按钮方法。

点击完成后，选择器视图向上滚动，而不是调用方法doneTouched：

@全部 提前致谢。

【问题讨论】：

您的选择器视图没有框架：CGRectMake(0,100,0,0)

我指出这一点是因为这很可能是您无法与工具栏交互的原因，因为从技术上讲，工具栏不在 UIPickerView 框架内。

@LyndseyScott 我无法弄清楚。我做错了什么。

尝试将 UIPickerView 设置为 pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0,100,self.view.frame.size.width,44)]; 之类的东西（与工具栏相同）

@LyndseyScott 这就是我所做的 pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0,self.view.frame.size.height-200,self.view.frame.size.width ,100)];对于工具栏 UIToolbar *toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width,42)];

【参考方案1】：

我已经解决了不知道是否正确实施的问题，但它对我有用。 下面是带有完成按钮的选择器视图的代码

-(void)createPickerView

    pickerToolBarView = [[UIView alloc]initWithFrame:CGRectMake(0,self.view.frame.size.height/2, self.view.frame.size.width,400)];
    [pickerToolBarView setBackgroundColor:[UIColor whiteColor]];

    UIToolbar *toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0,0,pickerToolBarView.frame.size.width,42)];
    toolBar.barStyle = UIBarStyleBlackOpaque;
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doneTouched:)];
    [toolBar setItems:[NSArray arrayWithObjects:[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil], doneButton, nil]];

    pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0,toolBar.frame.size.height,toolBar.frame.size.width,100)];
    [pickerView setDataSource: self];
    [pickerView setDelegate: self];
    pickerView.showsSelectionIndicator = YES;
    [pickerView setBackgroundColor:[UIColor whiteColor]];

    [pickerToolBarView addSubview:toolBar];
    [pickerToolBarView addSubview:pickerView];
    [self.view addSubview:pickerToolBarView];
    [self.view bringSubviewToFront:pickerToolBarView];
    [pickerToolBarView setHidden:YES];   


/* Done Touched */
- (void)doneTouched:(UIBarButtonItem *)sender
    // hide the  view
    NSLog(@"Done Touched");
    [pickerToolBarView setHidden:YES];

【参考方案2】：

而不是将工具栏添加为子视图：

yourTextField.inputAccessoryView = toolBar;

【讨论】：

如果我没有文本字段怎么办？

【参考方案3】：

我遇到了同样的问题。我的问题是我没有将选择器直接绑定到文本字段，而是从按钮中调出选择器。当我完成时，我还想要一个“完成”按钮来摆脱选择器。我认为问题在于我将工具栏作为选择器视图的一部分，并且由于某种原因我无法让按钮工作。我所做的是使工具栏成为视图的子视图，并将其 y 值设置为选择器的角 - 44。这将其移动到选择器的顶部并允许按钮工作。 这里有很多关于这个问题的问题，但似乎没有一个对我有用。我从 Gabriel Theodoropoulos 在他的网站上的示例开始：http://gabriel-tips.blogspot.com/2011/04/uipickerview-add-it-programmatically_04.html 并做了一些改动。这是我想出的，它似乎对我有用：

在.h文件中：

`   
    @interface Detail() <UIPickerViewDataSource, UIPickerViewDelegate>
    @property (nonatomic, retain) IBOutlet UIPickerView *picker;
    @property (nonatomic, retain) NSArray *pickerData;
    @property (assign, nonatomic) NSInteger pickerRowSelected;
    @property (nonatomic, retain) UIBarButtonItem *barButtonDone;
    @property (nonatomic, retain) UIToolbar *toolBar;
    @end

`

.m 文件中：`

-(void)showPicker
    // Calculate the screen's width.
    float screenWidth = [UIScreen mainScreen].bounds.size.width;
    float pickerWidth = screenWidth * 3 / 4;

    // Calculate the starting x coordinate.
    float xPoint = screenWidth / 2 - pickerWidth / 2;

    // Init the picker view.
    picker = [[UIPickerView alloc] init];

    // Set the delegate and datasource. Don't expect picker view to work
    // correctly if you don't set it.
    [picker setDataSource: self];
    [picker setDelegate: self];

    // Set the picker's frame. We set the y coordinate to 50px.
    [picker setFrame: CGRectMake(xPoint, 150.0f, pickerWidth, 200.0f)];

    // Before we add the picker view to our view, let's do a couple more
    // things. First, let the selection indicator (that line inside the
    // picker view that highlights your selection) to be shown.
    picker.showsSelectionIndicator = YES;

    // Allow us to pre-select the first option in the pickerView.
    [picker selectRow:0 inComponent:0 animated:YES];

    [picker setBackgroundColor:[UIColor grayColor]];

    toolBar= [[UIToolbar alloc] initWithFrame:CGRectMake(0,150-44,pickerWidth,44)];

    barButtonDone = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStylePlain target:self action:@selector(itemWasSelected:)];
    [toolBar setItems:[NSArray arrayWithObjects: barButtonDone, nil]];

    // OK, we are ready. Add the picker in our view.
    [self.view addSubview: picker];

    // Add the done button to the picker view
    [self.view addSubview:toolBar];
    [toolBar becomeFirstResponder];



// The number of columns of data
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

    return 1;


// The number of rows of data
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component

    return pickerData.count;


// The data to return for the row and component (column) that's being passed in
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component

    return pickerData[row];


// Catpure the picker view selection
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component

    // This method is triggered whenever the user makes a change to the picker selection.
    // The parameter named row and component represents what was selected.
    self.pickerRowSelected  = row;


-(IBAction)itemWasSelected:(id)sender

    NSLog(@"Picker selected = %@",[pickerData objectAtIndex: self.pickerRowSelected]);
    //NSLog(@"ID = %ld",(long)[self.thisData getIDForEntry:@"company" column:@"name" entry:[pickerData objectAtIndex: self.pickerRowSelected]]);
    [picker setHidden:YES];
    [toolBar setHidden:YES];




- (NSAttributedString *)pickerView:(UIPickerView *)pickerView attributedTitleForRow:(NSInteger)row forComponent:(NSInteger)component


    NSAttributedString *attString =
    [[NSAttributedString alloc] initWithString:[pickerData objectAtIndex:row] attributes:@NSForegroundColorAttributeName:[UIColor whiteColor]];

    return attString;


//bring up the size Picker
//This is tied to a button from IB and when pressed will bring up
//the picker.  The index returned is stored in self.pickerRowSelected 
- (IBAction)sizeButtonPressed:(id)sender 

    self.pickerData = [self.thisData getSizePickerData];
    [self showPicker];

` 我确信有更好的方法来实现这一点，但这对我有用，我现在正在使用它。

【参考方案4】：

我遇到了同样的问题。 问题是我将 UIToolbar 作为子视图添加到 UIPickerView。

这就是我为解决它所做的。

class MyViewController: UIViewController 
    var myPicker: UIPickerView!
    var myPickerToolBar: UIToolbar!

    func showPicker() 
         myPicker = UIPickerView()
         /*
         setup UIPickerView
         */
         view.addSubview(myPicker)

         myPickerToolBar = UIToolbar(frame: CGRect())
         /*
         setup UIToolbar with barButtons, one of barButtons runs hidePicker()
         */
         view.addSubview(myPickerToolBar)
    

    @objc func hidePicker() 
        myPicker.removeFromSuperview()
        myPickerToolBar.removeFromSuperview()