練習目標：http://www.youtube.com/watch?v=xiHBN2B1Vt4&list=UUPRP4bs_BNpx6XWI5Wm7O5g
老師範例：DrawSomething
我的作品：homework0810
在這個範例中，我使用了兩個viewController，去控制兩個頁面的畫面。
第一個用來顯示動畫的地方的viewController如下，
在這個頁面上除了球之外，還會有一個控制開關的鈕，當打開時代表不去管路徑如何直接讓球到圓點，
而關閉則會讓球一步步照著所繪的路線移動。
#import “ViewController.h”
@interface ViewController ()
@property (weak, nonatomic) IBOutlet UISwitch *straightSwitch;
@property (weak, nonatomic) IBOutlet UIImageView *myBall;
@end
@implementation ViewController
– (void)viewDidLoad
{
[super viewDidLoad];
}
– (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
/* 當切換畫面時會呼叫這個函數，可在此設定接收繪圖路徑資料的接收者為自己*/
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
if([segue.identifier isEqualToString:@”toDrawing”]){
ViewController2 * modalView = (ViewController2 *) segue.destinationViewController;
modalView.delegate = self;
}
}
/*這個函數是讓另一個ViewController去呼叫的，傳入path*/
-(void) DrawViewController:(ViewController2 *) ViewController path:(NSMutableArray *) path{
if([path count] == 0) return;
if(self.straightSwitch.on){
NSValue *value = [path objectAtIndex:[path count]-1];
[self performSelector:@selector(changePosition:) withObject:value afterDelay:0];
}else{
for (int i=0; i<[path count]; i++) {
NSValue *value = [path objectAtIndex:i];
[self performSelector:@selector(changePosition:) withObject:value afterDelay:i*0.1];
}
}
}
/*改變球的位置*/
-(void)changePosition:(NSValue *) value{
CGPoint point = [value CGPointValue];
CGRect rect = [self.myBall frame];
rect.origin.x = point.x - 25;
rect.origin.y = point.y - 25;
[self.myBall setFrame:rect];
}
@end[/code]
第二個view則是用來讓使用者繪製路線的地方，
在這邊我又將繪圖的地方獨立出來成為另一個繪圖版
而我讓view與繪圖間用notification來傳遞資料。
[code lang="c"]#import "ViewController2.h"
#import "DrawPanel.h"
@interface ViewController2 ()
@property (weak, nonatomic) IBOutlet UIImageView *myBall;
@property (weak, nonatomic) IBOutlet DrawPanel * myDrawPanel;
@end
@implementation ViewController2{
NSMutableArray * path;
}
@synthesize myDrawPanel;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
//註冊監聽事件
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(getPathData:) name:@"getPathData" object:nil];
}
//監聽繪圖版的繪圖事件接收器
-(void) getPathData:(NSNotification *) note{
NSDictionary *dict = [note userInfo];
path = [dict valueForKey:@"path"];
}
//將繪圖資料array傳回第一個view
- (IBAction)ActionBtnTouch:(id)sender {
[self dismissViewControllerAnimated:YES completion:^{
if([self.delegate respondsToSelector:@selector(DrawViewController:path:)]){
[self.delegate DrawViewController:self path:path];
}
}];
}
//在移除這個view時要順便將監聽事件移除
-(void)removeFromParentViewController{
[myDrawPanel removeObserver:self forKeyPath:@"price"];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
@end[/code]
這個則是繪圖版的code
[code lang="c"]#import "DrawPanel.h"
@implementation DrawPanel
@synthesize path;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
}
return self;
}
//每次碰觸時都清空array的值
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
path =[NSMutableArray array];
}
//移動時將所移動到的位置紀錄下來
-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
CGPoint touchLocation = [touch locationInView:self];
NSValue *value = [NSValue valueWithCGPoint:touchLocation];
[path addObject:value];
[self setNeedsDisplay];//請view更新畫面
}
//將資料傳給繪圖的view（發送notification）
-(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
[[NSNotificationCenter defaultCenter] postNotificationName:@"getPathData" object:self userInfo:[NSDictionary dictionaryWithObjectsAndKeys: path , @"path",nil]];
}
//實作繪圖方法
- (void)drawRect:(CGRect)rect{
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextBeginPath(context);
CGContextMoveToPoint(context, 55, 325);
for(int i = 0;i<[path count];i++){
NSValue *value = [path objectAtIndex:i];
CGPoint newPoint = [value CGPointValue];
CGContextAddLineToPoint(context, newPoint.x, newPoint.y);
}
//CGContextClosePath(context);
[[UIColor blackColor] setStroke];
CGContextDrawPath(context, kCGPathStroke);
}
@end[/code]
檔案下載：homework0810