iOS實現新年抽獎轉盤效果的思路

2020-07-26 02:21:47

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臨近春節，相信不少app都會加一個新的需求――新年抽獎

不多廢話，先上GIF效果圖

DEMO鏈接

1. 跑馬燈效果

2. 抽獎效果

實現步驟：

一、跑馬燈效果

其實很簡單，就是通過以下兩張圖片，用NSTimer無限替換，達到跑馬燈的效果

bg_lamp_1@2x.png

bg_lamp_2@2x.png

實現代碼：

_rotaryTable = [[UIImageView alloc] initWithFrame:CGRectMake((kScreenWidth-366*XT)/2, 218*XT, 366*XT, 318*XT)];_rotaryTable.tag = 100;[_rotaryTable setImage:[UIImage imageNamed:@"bg_lamp_1"]];[scrollView addSubview:_rotaryTable];_itemBordeTImer = [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(itemBordeTImerEvent) userInfo:nil repeats:YES];[[NSRunLoop currentRunLoop] addTimer:_itemBordeTImer forMode:NSRunLoopCommonModes];

- (void)itemBordeTImerEvent{ if (_rotaryTable.tag == 100) { _rotaryTable.tag = 101; [_rotaryTable setImage:[UIImage imageNamed:@"bg_lamp_2"]]; }else if (_rotaryTable.tag == 101){ _rotaryTable.tag = 100; [_rotaryTable setImage:[UIImage imageNamed:@"bg_lamp_1"]]; }}

二、抽獎效果

1.初始化獎品數組，以及按照 從上到下，從左到右 的順序布局UI界面

_itemTitleArray = @[@"3跳幣",@"嘉年華門票",@"8跳幣",@"10朵花",@"128朵花",@"2018跳幣",@"528跳幣",@"128跳幣",@"28朵花",@"88跳幣"];for (int i = 0 ; i < 4; i ++) { UIImageView *img = [[UIImageView alloc] initWithFrame:CGRectMake(i*82*XT, 0, 78*XT, 80*XT)]; [img setImage:[UIImage imageNamed:itemImgArray[i]]]; [itemView addSubview:img];  UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 63*XT, 78*XT, 13*XT)]; label.textAlignment = NSTextAlignmentCenter; label.textColor = [UIColor whiteColor]; label.font = [UIFont systemFontOfSize:13*XT]; label.text = _itemTitleArray[I]; [img addSubview:label]; }  for (int i = 0 ; i < 2; i ++) { UIImageView *img = [[UIImageView alloc] initWithFrame:CGRectMake(i*(78*XT+169*XT), 84*XT, 78*XT, 80*XT)]; [img setImage:[UIImage imageNamed:itemImgArray[i+4]]]; [itemView addSubview:img];  UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 63*XT, 78*XT, 13*XT)]; label.textAlignment = NSTextAlignmentCenter; label.textColor = [UIColor whiteColor]; label.font = [UIFont systemFontOfSize:13*XT]; label.text = _itemTitleArray[i+4]; [img addSubview:label]; }  for (int i = 0 ; i < 4; i ++) { UIImageView *img = [[UIImageView alloc] initWithFrame:CGRectMake(i*82*XT, 168*XT, 78*XT, 80*XT)]; [img setImage:[UIImage imageNamed:itemImgArray[i+6]]]; [itemView addSubview:img];  UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 63*XT, 78*XT, 13*XT)]; label.textAlignment = NSTextAlignmentCenter; label.textColor = [UIColor whiteColor]; label.font = [UIFont systemFontOfSize:13*XT]; label.text = _itemTitleArray[i+6]; [img addSubview:label]; }

2.點擊之后開始抽獎按鈕后，先快速地將選中框 正時針 轉三圈，再慢速地在 一圈之內 旋轉至中獎位置，請注意是按照 正時針 的順序旋轉，和UI布局的順序不一致，如圖所示：

- (void)getLotteryInfo{ // 快速旋轉計數，在NSTimer的方法下自增到29時結束，代表選中框快速旋轉了三圈，結束快速旋轉 _fastIndex = 0; // 慢速旋轉計數，在NSTimer的方法下自增到下面 _selectedIndex 的數字時，選中框到達中獎位置，結束慢速旋轉 _slowIndex = -1; // 中獎位置計數，按照順時針的順序，如上圖所示，若 _selectedIndex = 9 則獲得 9 所在位置的獎品 _selectedIndex = arc4random()%10;  // 根據獎品數組，獲取中獎信息 if (_selectedIndex<4) { _result = _itemTitleArray[_selectedIndex]; }else if (_selectedIndex == 4){ _result = @"2018跳幣"; }else if (_selectedIndex == 5){ _result = @"88跳幣"; }else if (_selectedIndex == 6){ _result = @"28朵花"; }else if (_selectedIndex == 7){ _result = @"128跳幣"; }else if (_selectedIndex == 8){ _result = @"528跳幣"; }else if (_selectedIndex == 9){ _result = @"128朵花"; } _itemBorderView.hidden = NO; // 開啟快速旋轉，時間間隔為0.1秒 _fastTimer = [NSTimer scheduledTimerWithTimeInterval:0.1 target:self selector:@selector(fastTimerEvent) userInfo:nil repeats:YES]; [[NSRunLoop currentRunLoop] addTimer:_fastTimer forMode:NSRunLoopCommonModes];}

3.NSTimer 快速旋轉事件

- (void)fastTimerEvent{ // _fastIndex 自增 _fastIndex = _fastIndex + 1; // 順時針移動選中框的位置 if (_fastIndex % 10 == 0) { [_itemBorderView setFrame:CGRectMake(-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 1){ [_itemBorderView setFrame:CGRectMake(82*XT-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 2){ [_itemBorderView setFrame:CGRectMake(2*82*XT-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 3){ [_itemBorderView setFrame:CGRectMake(3*82*XT-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 4){ [_itemBorderView setFrame:CGRectMake(3*82*XT-1*XT, 84*XT-1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 5){ [_itemBorderView setFrame:CGRectMake(3*82*XT-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 6){ [_itemBorderView setFrame:CGRectMake(2*82*XT-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 7){ [_itemBorderView setFrame:CGRectMake(82*XT-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 8){ [_itemBorderView setFrame:CGRectMake(-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_fastIndex % 10 == 9){ [_itemBorderView setFrame:CGRectMake(-1*XT, 84*XT-1*XT, 80*XT, 82*XT)]; } // _fastIndex = 29 時選中框結束快速旋轉，開啟慢速旋轉，時間間隔為0.45秒 if (_fastIndex >= 29) { [_fastTimer invalidate]; _slowTimer = [NSTimer scheduledTimerWithTimeInterval:0.45 target:self selector:@selector(slowTimerEvent) userInfo:nil repeats:YES]; [[NSRunLoop currentRunLoop] addTimer:_slowTimer forMode:NSRunLoopCommonModes]; }}

4.NSTimer 慢速旋轉事件

// 慢速移動動畫- (void)slowTimerEvent{ // _slowIndex 自增 _slowIndex = _slowIndex + 1; // 順時針移動轉中框的位置 if (_slowIndex % 10 == 0) { [_itemBorderView setFrame:CGRectMake(-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 1){ [_itemBorderView setFrame:CGRectMake(82*XT-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 2){ [_itemBorderView setFrame:CGRectMake(2*82*XT-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 3){ [_itemBorderView setFrame:CGRectMake(3*82*XT-1*XT, -1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 4){ [_itemBorderView setFrame:CGRectMake(3*82*XT-1*XT, 84*XT-1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 5){ [_itemBorderView setFrame:CGRectMake(3*82*XT-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 6){ [_itemBorderView setFrame:CGRectMake(2*82*XT-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 7){ [_itemBorderView setFrame:CGRectMake(82*XT-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 8){ [_itemBorderView setFrame:CGRectMake(-1*XT, 2*84*XT-1*XT, 80*XT, 82*XT)]; }else if (_slowIndex % 10 == 9){ [_itemBorderView setFrame:CGRectMake(-1*XT, 84*XT-1*XT, 80*XT, 82*XT)]; } // 當 _slowIndex >= _selectedIndex 時選中框結束慢速旋轉，開啟中獎獎品界面 if (_slowIndex >= _selectedIndex) { [_slowTimer invalidate]; dispatch_time_t delayTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.5/*延遲執行時間*/ * NSEC_PER_SEC)); dispatch_after(delayTime, dispatch_get_main_queue(), ^{ self.startButton.userInteractionEnabled = YES; [self showLotteryRlesultView]; }); }}

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。

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