多个UIPickerViews [英] Multiple UIPickerViews

问题描述

我有一个困境，我有两个UIPickerViews显示当两个不同的视图加载。我开始使用一个 UIPickerView ，并通过加载数组和所有其他 UIPickerView 操作来实现和运行在ViewController内。

我以为可以像新的 UIPickerView 一样复制/粘贴相同的方法，但只是更改变量名称也在同一个 UIViewController 中。

问题是 - UIPickerView 在下拉列表中显示相同的数据集？我只是在这里忘了一些明显的东西吗？

以下更新

我对下面所有四种方法都这样做了，一旦加载了下一个视图，应用程序会崩溃？这样吗？

   - （NSInteger）numberOfComponentsInPickerView：（UIPickerView *）thePickerView 
 
  - （NSInteger）thePickerView :( UIPickerView *）thePickerView numberOfRowsInComponent：（NSInteger）组件
 
  - （NSString *）thePickerView：（UIPickerView *）thePickerView titleForRow :( NSInteger）行forComponent：（NSInteger）组件
 
 - （void）thePickerView：（UIPickerView *）thePickerView didSelectRow :( NSInteger）行inComponent：（NSInteger）组件
  

解决方案

是的，您必须使用UIPickerView参数来确定WHICH选择器视图实际上是要求数据 - 因为您已将两个选择器都设置为相同的数据源。

   - （void）numberOfComponentInPickerView :( UIPickerView *）thePickerView {
 if（thePickerView == firstPickerView）{
 //返回第一个选择器中的组件数
} else if（thePickerView == secondPickerView）{
 // return第二个选择器中的组件数
} else {
 assert（NO）; 
} 
} 
 
 //重复所有其他委托/数据源方法
  

I have a dilemma, I have two UIPickerViews which "show" when two distinct views load. I started with one UIPickerView and was able to get that up and running by loading the array and all the other UIPickerView actions within the ViewController.

I thought it would be as simple as copy/pasting the same methods for the new UIPickerView, but just changing the variable names, also within the same UIViewController.

Problem is - both UIPickerView are showing the same data set in the drop down ? Am I simply missing something obvious here?

Updated below

I did that for all four methods below and now that app crashes once the "next" view is loaded? Does this look right?

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView 

- (NSInteger)thePickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component

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

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

解决方案

Yeah you are, you have to use the UIPickerView argument to determine WHICH picker view is actually asking for data - since you have set both pickers to the same data source.

-(void)numberOfComponentInPickerView:(UIPickerView*)thePickerView {
    if(thePickerView == firstPickerView) {
       // return number of components in first picker    
    } else if(thePickerView == secondPickerView) {    
       // return number of components in second picker    
    } else {
       assert(NO);
    }
}

// repeat for all other delegate / datasource methods

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