进度显示例子学习

进度显示例子学习

Cocoa Touch提供用于通知用户等待进程完成的类：1、UIActivityIndicatorView:提供一个旋转的圆，通知用户等待，不提供具体信息2、UIProgressView:显示进度条，量化工作量（时间）3、UIProgressHUD:不量化工作，但显示工作状态或描绘进度。注意此类不在标准的SDK中针对以上三类，分别用代码来演示应用1\

#define INDICATOR_VIEW 999 @interface HelloController : UIViewController{ BOOL progressShowing;} @end @implementation HelloController - ( void ) performAction{ UIActivityIndicatorView * activityIndicator = (UIActivityIndicatorView * )[self.view viewWithTag:INDICATOR_VIEW]; if (progressShowing) [activityIndicator stopAnimating]; else [activityIndicator startAnimating]; progressShowing = ! progressShowing;} - ( id ) init{ if (self = [super init]) self.title = @" Hello World " ; return self;} - ( void )loadView{ UIView * contentView = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]]; self.view = contentView; contentView.backgroundColor = [UIColor whiteColor]; [contentView release]; self.navigationItem.rightBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle: @" Do It " style:UIBarButtonItemStylePlain target:self action:@selector(performAction)] autorelease]; // Add the progress indicator but do not start it progressShowing = NO; UIActivityIndicatorView * activityIndicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake( 0.0f , 0.0f , 32.0f , 32.0f )]; [activityIndicator setCenter:CGPointMake( 160.0f , 208.0f )]; [activityIndicator setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleGray]; activityIndicator.tag = INDICATOR_VIEW; [contentView addSubview:activityIndicator]; [activityIndicator release];} @end

代码中个人觉得关键的地方在：progressShowing和activityIndicator.tag = INDICATOR_VIEW;[contentView addSubview:activityIndicator];2\扩展UIActionSheet函数

@interface UIActionSheet (extended) - ( void ) setNumberOfRows: (NSInteger) rows; - ( void ) setMessage: (NSString * )message; @end

//Timer事件处理

- ( void ) incrementBar: ( id ) timer{ amountDone += 1.0f ; UIProgressView * progbar = (UIProgressView * )[self.baseSheet viewWithTag:PROGRESS_BAR]; [progbar setProgress: (amountDone / 20.0 )]; if (amountDone > 20.0 ) { [self.baseSheet dismissWithClickedButtonIndex: 0 animated:YES]; [timer invalidate]; }}

//呈现视图

- ( void ) presentSheet{ if ( ! self.baseSheet) { baseSheet = [[UIActionSheet alloc] initWithTitle: @" Please Wait " delegate :self cancelButtonTitle:nil destructiveButtonTitle: nil otherButtonTitles: nil]; [baseSheet setNumberOfRows: 5 ]; [baseSheet setMessage: @" Updating Internal Databases " ]; UIProgressView * progbar = [[UIProgressView alloc] initWithFrame:CGRectMake( 50.0f , 70.0f , 220.0f , 90.0f )]; progbar.tag = PROGRESS_BAR; [progbar setProgressViewStyle: UIProgressViewStyleDefault]; [baseSheet addSubview:progbar]; [progbar release]; } UIProgressView * progbar = (UIProgressView * )[self.view viewWithTag:PROGRESS_BAR]; [progbar setProgress:(amountDone = 0.0f )]; [NSTimer scheduledTimerWithTimeInterval: 0.5 target: self selector: @selector(incrementBar:) userInfo: nil repeats: YES]; [baseSheet showInView:self.view];}

注意释放函数

- ( void ) dealloc{ // 释放baseSheet if (self.baseSheet) [self.baseSheet release]; [super dealloc];}

此例Timer来定时更新进度条状态为了显示进度状态，特用了UIActionSheet来处理在XCode4上执行，看不到应有的效果~~杯具中，看后续怎么处理另外，        [baseSheet setNumberOfRows:5];        [baseSheet setMessage:@"Updating Internal Databases"];没有执行应有的效果~~~3\声明已存在的类

- ( void ) dealloc{ // 释放baseSheet if (self.baseSheet) [self.baseSheet release]; [super dealloc];}

控制器中部分代码

- ( void ) killHUD: ( id ) aHUD{ [aHUD show:NO]; [aHUD release];} - ( void ) presentSheet{ id HUD = [[UIProgressHUD alloc] initWithWindow:[self.view superview]]; [HUD setText: @" Downloading File. Please wait. " ]; [HUD show:YES]; [self performSelector:@selector(killHUD:) withObject:HUD afterDelay: 5.0 ];}

类学习：UIActivityIndicatorView类The UIActivityIndicatorView class creates and manages an indicator showing the indeterminate progress of a task.UIActivityIndicatorView类创建并管理指示器，此指示器用于显示当前任务的进度。方法：    – initWithActivityIndicatorStyle:    – startAnimating    – stopAnimating    – isAnimating    属性：      hidesWhenStopped表示当动画结束后此视图是否隐藏      activityIndicatorViewStyle指示器视图样式UIProgressView类方法：    – initWithProgressViewStyle:属性：    progress：进度，float，0.0-1.0    progressViewStyle：进度视图样式    未公开：UIProgressHUD类    UIActionSheet的部分函数：- (void) setNumberOfRows: (NSInteger) rows;- (void) setMessage: (NSString *)message;

posted on 2012-07-16 23:21 linyawen 阅读( ...) 评论( ...) 编辑 收藏

转载于:https://www.cnblogs.com/linyawen/archive/2012/07/16/2594430.html