iphone - 保存 View 时出现两个PickerViews问题？

我试图在同一 View 中有2 pickerviews。它起作用，除了两件事。如果一个pickerview的行多于另一个，则当从pickerview中选择包含更多项目的项目时，应用程序将崩溃。我还为pickerviews创建了一个NSLog，控制台显示我一次选择了两个项目，而实际上我只在处理一个pickerview。我知道这听起来有些混乱，但是我包含了所有代码。先感谢您。

list和list2是NSMutableArrays

清单有4个项目
list2有5个项目

出现错误:

*由于未捕获的异常“NSRangeException”而终止应用程序，原因:“* -[NSCFArray objectAtIndex:]:索引(4)超出范围(4)”

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView{
    if([thePickerView isEqual:pickerView1 ]){
        return 1;
    }
    else if([thePickerView isEqual:pickerView2]){

        return  1;
    }

    else{
        return 0;
    }
}

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

    if([thePickerView isEqual:pickerView1 ]){
        return [list count];
    }
    else if([thePickerView isEqual:pickerView2]){
        return [list2 count];
    }

    else{
        return 0;
    }
}

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

    if([thePickerView isEqual:pickerView1 ]){
        return [list objectAtIndex:row];
    }
    else if([thePickerView isEqual:pickerView2]){
        return [list2 objectAtIndex:row];
    }

    else{
        return 0;
    }

}

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

    NSLog(@"Selected item %@. Index of selected item:%i", [list objectAtIndex:row], row);
    NSLog(@"Selected item %@. Index of selected item:%i", [list2 objectAtIndex:row], row);
    NSLog(@"Selected item %@. Index of selected item:%i", [list3 objectAtIndex:row], row);

if([thePickerView isEqual:pickerView1 ]){
//Do Something
}
else if([thePickerView isEqual:pickerView2 ]){
//Do Something
}
else if([thePickerView isEqual:pickerView3 ]){
//Do Something
}
}

最佳答案

您的问题在这里:

NSLog(@"Selected item %@. Index of selected item:%i", [list objectAtIndex:row], row);
NSLog(@"Selected item %@. Index of selected item:%i", [list2 objectAtIndex:row], row);
NSLog(@"Selected item %@. Index of selected item:%i", [list3 objectAtIndex:row], row);

发生的情况是，向​​上述列表之一发送了一条消息，以返回超出其范围的对象。在将消息发送到日志之前，您应该检查 call 来自哪个选择器:

if([thePickerView isEqual:pickerView1 ]){
  NSLog(@"Selected item %@. Index of selected item:%i", [list objectAtIndex:row], row);
  //Do Something
}
else if([thePickerView isEqual:pickerView2 ]){
  NSLog(@"Selected item %@. Index of selected item:%i", [list2 objectAtIndex:row], row);
  //Do Something
}
else if([thePickerView isEqual:pickerView3 ]){
  NSLog(@"Selected item %@. Index of selected item:%i", [list3 objectAtIndex:row], row);
  //Do Something
}

关于iphone - 保存 View 时出现两个PickerViews问题？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/2484858/