我正在使用TreeViewer并创建作业以刷新添加4k - 5k节点的Treeview。在刷新作业中，我调用Display.getDefault().asyncExec来执行getTreeViewer().refresh()方法。但是，我遇到了getTreeViewer().refresh()必须等待运行4000毫秒或更多的问题。这是在Ubuntu，Windows必须等待超过30000ms。
我不知道为什么必须等待很长时间才能执行。
答案 0 :(得分：3)
#import "YourViewController.h"
@interface YourViewController ()<UIPickerViewDataSource,UIPickerViewDelegate>
{
UIPickerView *productPicker;
NSArray *productListArray;
IBOutlet UITextField *productDescription;
}
@end
- (void)viewDidLoad
{
[super viewDidLoad];
[self addPickerView];
}
-(void)addPickerView
{
productListArray = [[NSArray alloc]initWithObjects:@"myArray",@"Rohit",@"Change",@"Your view", nil];
[productDescription setPlaceholder:@"Product Description"];
productPicker = [[UIPickerView alloc]init];
productPicker.dataSource = self;
productPicker.delegate = self;
productPicker.showsSelectionIndicator = YES;
UIToolbar* toolBar = [[UIToolbar alloc] init];
toolBar.barStyle = UIBarStyleBlack;
toolBar.translucent = YES;
toolBar.tintColor = nil;
[toolBar sizeToFit];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc]initWithTitle:@"Done" style:UIBarButtonItemStyleDone target:self action:@selector(doneButton:)];
[toolBar setItems:[NSArray arrayWithObjects:doneButton, nil]];
productDescription.inputView = productPicker;
productDescription.inputAccessoryView = toolBar;
}
- (IBAction)doneButton:(id)sender
{
NSLog(@"Done Touched");
[productPicker removeFromSuperview];
[productPicker resignFirstResponder];
[self.view endEditing:YES];
}
#pragma mark - Text field delegates
- (void)textFieldDidBeginEditing:(UITextField *)textField {
productDescription.inputView = productPicker;
}
#pragma mark - Text field delegates
- (void)textFieldDidBeginEditing:(UITextField *)textField {
productDescription.inputView = productPicker;
}
#pragma mark - Picker View Data source
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
return 1;
}
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
return [productListArray count];
}
#pragma mark- Picker View Delegate
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
[productDescription setText:[productListArray objectAtIndex:row]];
}
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{
return [productListArray objectAtIndex:row];
}
在SWT用户界面线程上尽快运行。因此，如果它被延迟，其他东西必须使用该线程。由于你有一棵大树，可能是asyncExec构建了导致延迟的树（除非你在UI线程中运行需要很长时间的东西）。
对于大型树，您可能需要查看使用TreeViewer样式创建树并使用SWT.VIRTUAL内容提供商。