什么是iOS应用程序的android.widget.Toast等价物？

Question

我几个月前制作了Android应用程序.Toast类对我来说非常有用.我不需要考虑主线程和地方来显示它.我可以在任何地方展示它,然后离开它,它会自动消失.

Toast.makeToast(context, msg, Toast.LENGTH_SHORT).show();

而已.^^

iPhone怎么样？有像Toast这样的东西吗？只是显示消息,不需要关心它.它会自动消失.

Answer 1

我已经为Android写了很长时间了,我想念吐司.我实施了一个.需要代码？这个给你:

ToastView.h

#import <UIKit/UIKit.h>

@interface ToastView : UIView

@property (strong, nonatomic) NSString *text;

+ (void)showToastInParentView: (UIView *)parentView withText:(NSString *)text withDuaration:(float)duration;

@end

ToastView.m

#import "ToastView.h"

@interface ToastView ()
@property (strong, nonatomic, readonly) UILabel *textLabel;
@end
@implementation ToastView
@synthesize textLabel = _textLabel;

float const ToastHeight = 50.0f;
float const ToastGap = 10.0f;

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}

-(UILabel *)textLabel
{
    if (!_textLabel) {
        _textLabel = [[UILabel alloc] initWithFrame:CGRectMake(5.0, 5.0, self.frame.size.width - 10.0, self.frame.size.height - 10.0)];
        _textLabel.backgroundColor = [UIColor clearColor];
        _textLabel.textAlignment = NSTextAlignmentCenter;
        _textLabel.textColor = [UIColor whiteColor];
        _textLabel.numberOfLines = 2;
        _textLabel.font = [UIFont systemFontOfSize:13.0];
        _textLabel.lineBreakMode = NSLineBreakByCharWrapping;
        [self addSubview:_textLabel];

    }
    return _textLabel;
}

- (void)setText:(NSString *)text
{
    _text = text;
    self.textLabel.text = text;
}

+ (void)showToastInParentView: (UIView *)parentView withText:(NSString *)text withDuaration:(float)duration;
{

    //Count toast views are already showing on parent. Made to show several toasts one above another
    int toastsAlreadyInParent = 0;
    for (UIView *subView in [parentView subviews]) {
        if ([subView isKindOfClass:[ToastView class]])
        {
            toastsAlreadyInParent++;
        }
    }

    CGRect parentFrame = parentView.frame;

    float yOrigin = parentFrame.size.height - (70.0 + ToastHeight * toastsAlreadyInParent + ToastGap * toastsAlreadyInParent);

    CGRect selfFrame = CGRectMake(parentFrame.origin.x + 20.0, yOrigin, parentFrame.size.width - 40.0, ToastHeight);
    ToastView *toast = [[ToastView alloc] initWithFrame:selfFrame];

    toast.backgroundColor = [UIColor darkGrayColor];
    toast.alpha = 0.0f;
    toast.layer.cornerRadius = 4.0;
    toast.text = text;

    [parentView addSubview:toast];

    [UIView animateWithDuration:0.4 animations:^{
        toast.alpha = 0.9f;
        toast.textLabel.alpha = 0.9f;
    }completion:^(BOOL finished) {
        if(finished){

        }
    }];


    [toast performSelector:@selector(hideSelf) withObject:nil afterDelay:duration];

}

- (void)hideSelf
{

    [UIView animateWithDuration:0.4 animations:^{
        self.alpha = 0.0;
        self.textLabel.alpha = 0.0;
    }completion:^(BOOL finished) {
        if(finished){
            [self removeFromSuperview];
        }
    }];
}

@end

从ViewController调用

 [ToastView showToastInParentView:self.view withText:@"What a toast!" withDuaration:5.0];

Answer 2

UIKit 中没有“开箱即用”的类来执行此操作。但是创建一个提供这种行为的类是很容易的。

你只需要创建一个继承自 UIView 的类。此类将负责 - 创建您想要显示的内容， - 将自身添加到父视图层次结构中 - 使用计时器关闭自身。

您将能够像这样使用它：

[ToastView toastViewInView:myParentView withText:@"what a wonderful text"];

问候，昆汀