知識星球作者： iOS小菜鳥一枚
連結：https://blog.csdn.net/qq_27501365/article/details/86528422
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連結：https://gitee.com/xudongxiang/LuckyDraw.git
1、跑馬燈效果
2、抽獎效果
現步驟：
一、跑馬燈效果
其實很簡單，就是透過以下兩張圖片，用NSTimer無限替換，達到跑馬燈的效果
實現程式碼：
_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、初始化獎品陣列，以及按照 從上到下，從左到右 的順序佈局UI介面
_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、點選之後開始抽獎按鈕後，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 註意 是按照 正時針 的順序旋轉，和UI佈局的順序不一致，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的方法下自增到下麵 _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;
// 根據獎品陣列，獲取中獎資訊
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，開啟中獎獎品介面
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];
});
}
}
