1、寫了一個小Demo，實現上下移動的效果圖：              主要代碼如下： [cpp] - (IBAction)upChange:(id)sender {       if (typeView == down) {           [self.downBtn setHidden:NO];           [self.upBtn setHidden:NO];           [UIView animateWithDuration:0.5 animations:^{               self.upView.center = CGPointMake(self.upView.center.x, 0);                self.downView.center = CGPointMake(self.downView.center.x, (self.upView.frame.size.height+self.downView.frame.size.height)/2);           }];                      typeView = middle;       }else if(typeView == middle){           [self.downBtn setHidden:NO];           [self.upBtn setHidden:YES];           [UIView animateWithDuration:0.5 animations:^{               self.upView.center = CGPointMake(self.upView.center.x, -(self.upView.frame.size.height/2));               self.downView.center = CGPointMake(self.downView.center.x, self.downView.frame.size.height/2);           }];                      typeView = up;       }      }      - (IBAction)downChange:(id)sender {       if (typeView == middle) {           [self.downBtn setHidden:YES];           [self.upBtn setHidden:NO];           [UIView animateWithDuration:0.5 animations:^{               self.upView.center = CGPointMake(self.upView.center.x, self.upView.frame.size.height/2);                self.downView.center = CGPointMake(self.downView.center.x, self.upView.frame.size.height+self.downView.frame.size.height/2);           }];              typeView = down;       }else if(typeView == up)       {           [self.downBtn setHidden:NO];           [self.upBtn setHidden:NO];           [UIView animateWithDuration:0.5 animations:^{               self.upView.center = CGPointMake(self.upView.center.x, 0);               self.downView.center = CGPointMake(self.downView.center.x, (self.upView.frame.size.height+self.downView.frame.size.height)/2);           }];                      typeView = middle;       }      }     - (IBAction)upChange:(id)sender {     if (typeView == down) {         [self.downBtn setHidden:NO];         [self.upBtn setHidden:NO];         [UIView animateWithDuration:0.5 animations:^{             self.upView.center = CGPointMake(self.upView.center.x, 0);              self.downView.center = CGPointMake(self.downView.center.x, (self.upView.frame.size.height+self.downView.frame.size.height)/2);         }];                  typeView = middle;     }else if(typeView == middle){         [self.downBtn setHidden:NO];         [self.upBtn setHidden:YES];         [UIView animateWithDuration:0.5 animations:^{             self.upView.center = CGPointMake(self.upView.center.x, -(self.upView.frame.size.height/2));             self.downView.center = CGPointMake(self.downView.center.x, self.downView.frame.size.height/2);         }];                  typeView = up;     }   }   - (IBAction)downChange:(id)sender {     if (typeView == middle) {         [self.downBtn setHidden:YES];         [self.upBtn setHidden:NO];         [UIView animateWithDuration:0.5 animations:^{             self.upView.center = CGPointMake(self.upView.center.x, self.upView.frame.size.height/2);              self.downView.center = CGPointMake(self.downView.center.x, self.upView.frame.size.height+self.downView.frame.size.height/2);         }];           typeView = down;     }else if(typeView == up)     {         [self.downBtn setHidden:NO];         [self.upBtn setHidden:NO];         [UIView animateWithDuration:0.5 animations:^{             self.upView.center = CGPointMake(self.upView.center.x, 0);             self.downView.center = CGPointMake(self.downView.center.x, (self.upView.frame.size.height+self.downView.frame.size.height)/2);         }];                  typeView = middle;     }   }       這是主要的代碼，另外還有一些需要注意的一些小細，如你的兩個view的大小，需要計算出精確位置。     下面開始學習[UIView animateWithDuration]方法的使用： 函數原型： + (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations __OSX_AVAILABLE_STARTING(__MAC_NA,__IPHONE_4_0); // delay = 0.0, options = 0, completion = NULL   duration：動畫持續時間 animations：該代碼兒塊中是所有view要完成的動畫的所有屬性的定義； 還有另外兩個函數： + (void)animateWithDuration:(NSTimeInterval)duration delay:(NSTimeInterval)delay options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion __OSX_AVAILABLE_STARTING(__MAC_NA,__IPHONE_4_0);       + (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion__OSX_AVAILABLE_STARTING(__MAC_NA,__IPHONE_4_0);// delay = 0.0, options = 0       options:是動畫執行的選項 completion：是動畫完成以後所要執行的代碼塊兒。