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();
就是这样。 ^^
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。
答案 0 :(得分：72)
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？你在这里：
<强> 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
<强> 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];
答案 1 :(得分：4)
UIKit中没有“开箱即用”的课程来执行此操作。但是创建一个可以提供这种行为的类很容易。
您只需要创建一个继承自UIView的类。这门课有责任 - 创建您想要显示的内容， - 在父视图层次结构中添加自身 - 使用计时器解雇自己。
您可以像以下一样使用它：
[ToastView toastViewInView:myParentView withText:@"what a wonderful text"];
此致 昆汀
答案 2 :(得分：2)
没试过，但你可能想检查一下：
答案 3 :(得分：2)
编辑：已更新为Swift 3
这是一个基于wojciech_maciejewski的答案的Swift 3版本。这看起来更像Android Toast，并且不会互相堆叠祝酒。它将烤面包吐入屏幕中央。它可以处理长多行文本。
import UIKit
class ToastView: UIView {
private static let hLabelGap: CGFloat = 40.0
private static let vLabelGap: CGFloat = 20.0
private static let hToastGap: CGFloat = 20.0
private static let vToastGap: CGFloat = 10.0
private var textLabel: UILabel!
static func showInParent(_ parentView: UIView, _ text: String, duration: Double = 3.0) {
let labelFrame = CGRect(x: parentView.frame.origin.x + hLabelGap,
y: parentView.frame.origin.y + vLabelGap,
width: parentView.frame.width - 2 * hLabelGap,
height: parentView.frame.height - 2 * vLabelGap)
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 15.0)
label.text = text
label.backgroundColor = UIColor.clear
label.textAlignment = NSTextAlignment.center
label.textColor = UIColor.white
label.numberOfLines = 0
label.frame = labelFrame
label.sizeToFit()
let toast = ToastView()
toast.textLabel = label
toast.addSubview(label)
toast.frame = CGRect(x: label.frame.origin.x - hToastGap,
y: label.frame.origin.y - vToastGap,
width: label.frame.width + 2 * hToastGap,
height: label.frame.height + 2 * vToastGap)
toast.backgroundColor = UIColor.darkGray
toast.alpha = 0.0
toast.layer.cornerRadius = 20.0
toast.center = parentView.center
label.center = CGPoint(x: toast.frame.size.width / 2, y: toast.frame.size.height / 2)
parentView.addSubview(toast)
UIView.animate(withDuration: 0.4, animations: {
toast.alpha = 0.9
label.alpha = 0.9
})
toast.perform(#selector(hideSelf), with: nil, afterDelay: duration)
}
@objc private func hideSelf() {
UIView.animate(withDuration: 0.4, animations: {
self.alpha = 0.0
self.textLabel.alpha = 0.0
}, completion: { t in self.removeFromSuperview() })
}
}
来自其他控制器的用法：
ToastView.showInParent(navigationController!.view, "Hello world")
答案 4 :(得分：1)
我发布了Scarmysun的快速版本答案:)非常感谢
import Foundation
import UIKit
class ToastView: UIView {
static let toastHeight:CGFloat = 50.0
static let toastGap:CGFloat = 10;
lazy var textLabel: UILabel = UILabel(frame: CGRectMake(5.0, 5.0, self.frame.size.width - 10.0, self.frame.size.height - 10.0))
static func showInParent(parentView: UIView!, withText text: String, forDuration duration: double_t) {
//Count toast views are already showing on parent. Made to show several toasts one above another
var toastsAlreadyInParent = 0;
for view in parentView.subviews {
if (view.isKindOfClass(ToastView)) {
toastsAlreadyInParent++
}
}
var parentFrame = parentView.frame;
var yOrigin = parentFrame.size.height - getDouble(toastsAlreadyInParent)
var selfFrame = CGRectMake(parentFrame.origin.x + 20.0, yOrigin, parentFrame.size.width - 40.0, toastHeight);
var toast = ToastView(frame: selfFrame)
toast.textLabel.backgroundColor = UIColor.clearColor()
toast.textLabel.textAlignment = NSTextAlignment.Center
toast.textLabel.textColor = UIColor.whiteColor()
toast.textLabel.numberOfLines = 2
toast.textLabel.font = UIFont.systemFontOfSize(13.0)
toast.addSubview(toast.textLabel)
toast.backgroundColor = UIColor.darkGrayColor()
toast.alpha = 0.0;
toast.layer.cornerRadius = 4.0;
toast.textLabel.text = text;
parentView.addSubview(toast)
UIView.animateWithDuration(0.4, animations: {
toast.alpha = 0.9
toast.textLabel.alpha = 0.9
})
toast.performSelector(Selector("hideSelf"), withObject: nil, afterDelay: duration)
}
static private func getDouble(toastsAlreadyInParent : Int) -> CGFloat {
return (70.0 + toastHeight * CGFloat(toastsAlreadyInParent) + toastGap * CGFloat(toastsAlreadyInParent));
}
func hideSelf() {
UIView.animateWithDuration(0.4, animations: {
self.alpha = 0.0
self.textLabel.alpha = 0.0
}, completion: { t in self.removeFromSuperview() })
}
}
答案 5 :(得分：0)
您可以通过多种方式执行此操作，其中一种方法是使用UIAlertViewController()中的swift3
let alertManager=UIAlertController(title: nil, message: "Welcome!", preferredStyle: .alert)
self.present(alertManager, animated: true, completion: nil)
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now()+1,
execute: {
alertManager.dismiss(animated: false, completion: nil)
})