IOS——自定义iOS状态栏

如果需要在状态栏显示自定义的消息时，就需要自定义状态栏。

代码如下：

XYCustomStatusBar.h

#import <UIKit/UIKit.h>

@interface XYCustomStatusBar : UIWindow{
    
    UILabel *_messageLabel;
}

- (void)showStatusMessage:(NSString *)message;

- (void)hide;

@end

XYCustomStatusBar.m

#import "XYCustomStatusBar.h"

@implementation XYCustomStatusBar

- (void)dealloc{
    [super dealloc];
    [_messageLabel release], _messageLabel = nil;
}

- (id)init{
    self = [super init];
    if (self) {
        self.frame = [UIApplication sharedApplication].statusBarFrame;
        self.backgroundColor = [UIColor blackColor];
        self.windowLevel = UIWindowLevelStatusBar + 1.0f;
        
        _messageLabel = [[UILabel alloc] initWithFrame:self.bounds];
        [_messageLabel setTextColor:[UIColor whiteColor]];
        [_messageLabel setTextAlignment:NSTextAlignmentRight];
        [_messageLabel setBackgroundColor:[UIColor clearColor]];
        [self addSubview:_messageLabel];
    }
    
    return self;
}

- (void)showStatusMessage:(NSString *)message{
    self.hidden = NO;
    self.alpha = 1.0f;
    _messageLabel.text = @"";
    
    CGSize totalSize = self.frame.size;
    self.frame = (CGRect){ self.frame.origin, 0, totalSize.height };
    
    [UIView animateWithDuration:0.5 animations:^{
        self.frame = (CGRect){self.frame.origin, totalSize };
    } completion:^(BOOL finished){
        _messageLabel.text = message;
    }];
    
}


- (void)hide{
    self.alpha = 1.0f;
    
    [UIView animateWithDuration:0.5f animations:^{
        self.alpha = 0.0f;
    } completion:^(BOOL finished){
        _messageLabel.text = @"";
        self.hidden = YES;
    }];
}

@end

为了让自定义的状态栏可以让用户看到，设置了它的windowlevel，在ios中，windowlevel属性决定了UIWindow的显示层次，默认的windowlevel为UIWindowLevelNormal，即0.0 。为了能覆盖默认的状态栏，将windowlevel设置高点。其他代码基本上都不解释什么，如果要特殊效果，可以自己添加。