学步园

  

一、新建一个single view application工程，并且添加相关的控件并拖拽连接：
如下图：

新建一个OC类，继承自UIWindow，如下图：


CustomWindow.h:

#import <UIKit/UIKit.h>

@interface CustomWindow :UIWindow {

    UIView *superView;

    UIView *backgroundView;

    UIImageView *backgroundImage;

    UIView *contentView;

    BOOL closed;

}

@property (nonatomic,retain)UIView *superView;

@property (nonatomic,retain)UIView *backgroundView;

@property (nonatomic,retain)UIImageView *backgroundImage;

@property (nonatomic,retain)UIView *contentView;

-(CustomWindow *)initWithView:(UIView *)aView;

-(void)show;

-(void)close;

@end

CustomWindow.m:

#import "CustomWindow.h"

@implementation CustomWindow

@synthesize superView;

@synthesize backgroundView;

@synthesize backgroundImage;

@synthesize contentView;

-(UIImage *) pngWithPath:(NSString *)path

{

    NSString *fileLocation = [[NSBundlemainBundle]pathForResource:path ofType:@"png"]; 

    NSData *imageData = [NSDatadataWithContentsOfFile:fileLocation]; 

    UIImage *img=[UIImageimageWithData:imageData];

    return img;

}

-(CustomWindow *)initWithView:(UIView *)aView

{

    if (self=[superinit]) {       

        //内容view

        self.contentView = aView;

        //初始化主屏幕

        [selfsetFrame:[[UIScreenmainScreen]bounds]];

        self.windowLevel =UIWindowLevelStatusBar;

        self.backgroundColor = [UIColorcolorWithRed:0green:0blue:0 alpha:0.1];

        //添加根view，并且将背景设为透明.

        UIView *rv = [[UIViewalloc]initWithFrame:[selfbounds]];

        self.superView = rv;

        [superViewsetAlpha:0.0f];

        [self addSubview:superView];

        [rv release];

        //设置background view.

        CGFloat offset = -6.0f;

        UIView *bv = [[UIViewalloc]initWithFrame:CGRectInset(CGRectMake(0,0,self.contentView.bounds.size.width,self.contentView.bounds.size.height),
offset, offset)];

        self.backgroundView = bv;

        [bv release];

        //用圆角png图片设为弹出窗口背景.

        UIImageView *bi = [[UIImageViewalloc]initWithImage:[[selfpngWithPath:@"alert_window_bg"]stretchableImageWithLeftCapWidth:13.0topCapHeight:9.0]];

        self.backgroundImage = bi;

        [backgroundImagesetFrame:[backgroundViewbounds]];

        [backgroundViewinsertSubview:backgroundImageatIndex:0];

        [backgroundViewsetCenter:CGPointMake(superView.bounds.size.width/2,superView.bounds.size.height/2)];

        [superViewaddSubview:backgroundView];

        CGRect frame =CGRectInset([backgroundViewbounds], -1 * offset, -1 * offset);

        //显示内容view

        [backgroundViewaddSubview:self.contentView];

        [self.contentViewsetFrame:frame];

        closed =NO;

    }

    returnself;

}

//显示弹出窗口

-(void)show

{

    [selfmakeKeyAndVisible];

    [superView setAlpha:1.0f]; 

}

-(void)dialogIsRemoved

{

    closed = YES;

    [contentViewremoveFromSuperview];

    contentView =nil;

    [backgroundViewremoveFromSuperview];

    backgroundView =nil;

    [superViewremoveFromSuperview];

    superView =nil;

    [self setAlpha:0.0f];

    [selfremoveFromSuperview];

    self = nil;

//    NSLog(@"===> %s, %s, %d", __FUNCTION__, __FILE__, __LINE__);

}

-(void)close

{

    [UIViewsetAnimationDidStopSelector:@selector(dialogIsRemoved)];

    [superView setAlpha:0.0f];

//    NSLog(@"===> %s, %s, %d", __FUNCTION__, __FILE__, __LINE__);

}

接下来，在CustomAlertWindowViewController中添加该自定义CustomWindow对象成员，并添加一个button属性与XIB界面上的Press Me!按钮相连接，如下图：

至此，CMD+R运行一下，是第一张图的效果，占击按钮没有反应，那是因为我们没有为该按钮添加相应的行为，接下来我们实现点击按钮弹出一个窗口，该窗口即由CustomAlertWindowViewController中的自定义窗口customWindow来呈现。看customWindow中的代码，需要添加一张圆角PNG图片做为背景，该PNG图片不一定要和该内容视图contentView大小一模一样，只需要四个角是圆角，中间是纯色即可，使用到一个经常用的函数CG_EXTERNCGRect CGRectInset(CGRect rect,CGFloat dx,CGFloat dy)，该方法可以实现四个角落不变，中间拉抻，具体该函数的解释请参考APPLE的官方文档，不多解释！将alert_window_bg.png添加至工程的Supporting
Files下即可。