【移动应用开发技术】iOS中UILabel如何实现长按复制功能

【移动应用开发技术】iOS中UILabel如何实现长按复制功能

前言常见的系统方法和使用-

(void)cut:(nullable

id)sender

NS_AVAILABLE_IOS(3_0);

-

(void)copy:(nullable

id)sender

NS_AVAILABLE_IOS(3_0);

-

(void)paste:(nullable

id)sender

NS_AVAILABLE_IOS(3_0);

-

(void)select:(nullable

id)sender

NS_AVAILABLE_IOS(3_0);

-

(void)selectAll:(nullable

id)sender

NS_AVAILABLE_IOS(3_0);

-

(void)delete:(nullable

id)sender

NS_AVAILABLE_IOS(3_2);//

比如我在一个

UITextView

里，想增加全选和复制的方法

//

只要在自定义

UITextView

的时候加入这行代码即可

-

(BOOL)canPerformAction:(SEL)action

withSender:(id)sender

{

if(action

==

@selector(selectAll:)

||

action

==

@selector(copy:))

return

YES;

return

NO;

}/upload/information/20200623/126/120823.png自定义方法和使用-

(BOOL)canBecomeFirstResponder

{

return

YES;

}-

(void)setUp

{

/*

你可以在这里添加一些代码，比如字体、居中、夜间模式等

*/

self.userInteractionEnabled

=

YES;

[self

addGestureRecognizer:[[UILongPressGestureRecognizer

alloc]initWithTarget:self

action:@selector(longPress)]];

}-

(void)longPress

{

//

设置label为第一响应者

[self

becomeFirstResponder];

//

自定义

UIMenuController

UIMenuController

*

menu

=

[UIMenuController

sharedMenuController];

UIMenuItem

*

item1

=

[[UIMenuItem

alloc]initWithTitle:@"复制"

action:@selector(copyText:)];

menu.menuItems

=

@[item1];

[menu

setTargetRect:self.bounds

inView:self];

[menu

setMenuVisible:YES

animated:YES];

}-

(BOOL)canPerformAction:(SEL)action

withSender:(id)sender

{

if(action

==

@selector(copyText:))

return

YES;

return

NO;

}

//

如果模仿上面的写以下代码，点击后会导致程序崩溃

if(action

==

@selector(selectAll:)

||

action

==

@selector(copy:))

return

YES;-

(void)copyText:(UIMenuController

*)menu

{

//

没有文字时结束方法

if

(!self.text)

return;

//

复制文字到剪切板

UIPasteboard

*

paste

=

[UIPasteboard

generalPast