// app从后台进入前台都会调用这个方法
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationBecomeActive) name:UIApplicationWillEnterForegroundNotification object:nil];
//读取剪切板的内容只从系统剪切板读区
//应用内保存到剪切板的内容在主动读取的时候需要过滤掉
@implementation PasteboardUtils
(NSString *)read {
//创建系统剪切板
UIPasteboard *systemBoard = [UIPasteboard generalPasteboard];
if(!systemBoard.numberOfItems) {
//剪切板为空
return nil;
}
if([self hasMark]) {
//剪切板数据已经标记过了，则数据来自当前应用，不予处理
return nil;
}
return systemBoard.string;
}(void)save:(NSString *)content {
//创建系统剪切板
UIPasteboard *systemBoard = [UIPasteboard generalPasteboard];
//将文本写入剪切板
systemBoard.string = content;
//给剪切板加入一条标记性的数据，只是为了检测剪切板的数据是否来自当前应用
NSDictionary<NSString *, id> *item = @{PASTEBOARD_MARK:content};
[systemBoard addItems:@[item]];
}(void)clear {
//创建系统剪切板
UIPasteboard *systemBoard = [UIPasteboard generalPasteboard];
systemBoard.string = @"";
}(BOOL)hasMark{
//创建系统剪切板
UIPasteboard *systemBoard = [UIPasteboard generalPasteboard];
if(!systemBoard.numberOfItems) {
return YES;
}
NSArray<NSDictionary<NSString *, id> *> *items = systemBoard.items;
long count = systemBoard.numberOfItems;
for(int i=0; i < count; i++){
NSDictionary<NSString *, id> *item = [items objectAtIndex:i];
if([[item allKeys] containsObject:PASTEBOARD_MARK]){
return YES;
}
}
return NO;
}
