(ios实战)实现类似于android 的toast控件

1实现原理

创建一个自定义控件，控件中显示文本，同时设置一个动画，三秒钟后，控件的alpha为0,动画完成后，控件移出掉ViewControl

2 创建PopView

2.1 PopView.h 部分

@interface PopView : UIView
{
UILabel         *_textLabel;
int             _queueCount;
}

- (void) setText:(NSString *) text;

@end

2.2 PopView.m

#import "PopView.h"
#import <QuartzCore/QuartzCore.h>
@implementation PopView

- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
self.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent: 0.75f];
self.layer.cornerRadius = 5.0f;
_textLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 100, 10)];
_textLabel.numberOfLines = 0;
_textLabel.font = [UIFont systemFontOfSize:17];
_textLabel.textColor = [UIColor whiteColor];
_textLabel.textAlignment = NSTextAlignmentCenter;
_textLabel.backgroundColor = [UIColor clearColor];
_textLabel.textAlignment = NSTextAlignmentCenter;
[self addSubview:_textLabel];
_queueCount = 0;
}
return self;
}

- (void) setText:(NSString *) text
{
_textLabel.frame = CGRectMake(0, 0, 100, 10);
_queueCount ++;
self.alpha = 1.0f;
_textLabel.text = text;
[_textLabel sizeToFit];
CGRect frame = CGRectMake(5, 0, _textLabel.frame.size.width, _textLabel.frame.size.height);
_textLabel.frame = frame;
frame =  CGRectMake(self.frame.origin.x, self.frame.origin.y, _textLabel.frame.size.width+10, _textLabel.frame.size.height+10);
self.frame = frame;
[UIView animateWithDuration:3.0
delay:0.0
options:UIViewAnimationOptionCurveEaseIn
animations:^{
self.alpha = 0;
}
completion:^(BOOL finished){
if (_queueCount == 1) {
[self removeFromSuperview];
}
_queueCount--;

}
];

}

@end

3 调用方式：

[self.view addSubview:_popView];
[_popView setText:@"合成恢复"];