UIView及繪圖練習範例APP

這個作業主要是在練習對view以及簡單的繪圖的操作，還有timer的使用
因此我截錄一些我覺得是練習關鍵的程式碼

下面的是viewController的相關程式碼

一個個出現的程式碼，按下show按鈕時觸發

- (IBAction)showButtonClick {
    [self clearButtonClick];
    [self.circleNumber resignFirstResponder];
    total = [self.circleNumber.text integerValue];
    index = 0;
    //設定間隔一個個產生circle
    [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(addItems:) userInfo:NULL repeats:YES];
}

- (IBAction)showButtonClick {

[self clearButtonClick];

[self.circleNumber resignFirstResponder];

total = [self.circleNumber.text integerValue];

index = 0;

//設定間隔一個個產生circle

[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(addItems:) userInfo:NULL repeats:YES];

}

取得圓圈排列坐標的程式碼，傳入值為圓半徑及角度

//取得坐標
- (CGPoint)getPoint:(int) radius withAngel:(CGFloat) degrees{

    int y = sin(degrees * M_PI / 180)*radius;
    int x = cos(degrees * M_PI / 180)*radius;
    CGPoint btCorner = CGPointMake(x, y) ;
    return btCorner;
}

//取得坐標

- (CGPoint)getPoint:(int) radius withAngel:(CGFloat) degrees{

int y = sin(degrees * M_PI / 180)*radius;

int x = cos(degrees * M_PI / 180)*radius;

CGPoint btCorner = CGPointMake(x, y) ;

return btCorner;

}

下面的程式碼則是在被新增的UIView物件裡面

顯示動畫，這邊要注意的是因為定位點的關係，由於我們希望元件的縮放是以view的中心來做縮放
所以改變的值是self.bounds，一般我們在做元件內部繪圖事件，都會使用self.bounds
而self.frame則是在外部設定物件資訊時使用。

-(void) playAnimation{
    [UIView animateWithDuration:0.5f
                     animations:^{
                         self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 50, 50);
                     }completion:^(BOOL finished) {
                         [UIView animateWithDuration:0.5f
                                          animations:^{
                                               self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 30, 30);
                                          }completion:^(BOOL finished) {
                                          }];

                     }];
}

-(void) playAnimation{

[UIView animateWithDuration:0.5f

animations:^{

self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 50, 50);

}completion:^(BOOL finished) {

[UIView animateWithDuration:0.5f

animations:^{

self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 30, 30);

}completion:^(BOOL finished) {

}];

}

另外，因為- (id)initWithFrame:(CGRect)frame被呼叫的時間是在circle被新建的時後，而不是在被加到畫面時，
為了落實動畫的被執行時間，所以我又實作了layoutSubviews這個方法，
並加上BOOL init當今天是第一次被呼叫時，才會執行playAnimation

-(void)layoutSubviews{
    if(init){
        [self playAnimation];
        init = NO;
    }
}

-(void)layoutSubviews{

if(init){

[self playAnimation];

init = NO;

}

然後實作按下後縮小離開時恢復大小的功能

-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    [UIView animateWithDuration:0.2f
                     animations:^{
                         self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 0, 0);
                     }
                     completion:^(BOOL finished) {
                     }];
}

-(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{

    [UIView animateWithDuration:0.2f
                     animations:^{
                         self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 30, 30);
                     }
                     completion:^(BOOL finished) {
                     }];

}

-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

[UIView animateWithDuration:0.2f

animations:^{

self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 0, 0);

}

completion:^(BOOL finished) {

}];

}

-(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{

[UIView animateWithDuration:0.2f

animations:^{

self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, 30, 30);

}

completion:^(BOOL finished) {

}];

}

原始碼下載：homework0803