專案中需要使用自定義安全鍵盤，隨機佈局，鍵盤區域防截圖

1. 自定義鍵盤，通過自定義UITextField的inputView和inputAccessoryView實現

   • 首先確定鍵盤上所有的字元，數字、字母、符號、控制字元等；

     self.numbers = [@"0 1 2 3 4 5 6 7 8 9" componentsSeparatedByString:@" "];
     self.letters = [@"a b c d e f g h i j k l m n o p q r s backspace uppercase t u v w x y z return" componentsSeparatedByString:@" "];
     self.controls = [@"backspace uppercase return" componentsSeparatedByString:@" "];
     self.symbols = [@"~ ` ! @ # $ % ^ & * ( ) _ - + = { [ } ] | \\ : ; \" ' < , > backspace . ? / € ￡ ¥ space  return" componentsSeparatedByString:@" "];
      
     

   • 每個字元一個鍵位，點選字元設定輸入框內容，點選控制字元修改鍵盤或者輸入

     - (void)clickKey:(UIButton *)button {
         if ([self.controls containsObject:button.titleLabel.text] || button.titleLabel.text.length==0) {
             return;
         }
         NSString *inputKey = button.titleLabel.text;
         if ([button.titleLabel.text isEqualToString:@"space"]) {
             inputKey = @" ";
         }
         self.text = [NSString stringWithFormat:@"%@%@", self.text, inputKey];
         [self sendActionsForControlEvents:UIControlEventEditingChanged];//直接設定text不會觸發controlevent事件，需要呼叫此方法
     }
      
     

   • 開始編輯時，對所有字元隨機排序，並重新設定所有按鍵

     - (void)onBeginEditing {
         self.numbers = [self shuffleArray:self.numbers];
         self.letters = [self shuffleArray:self.letters];
     //    self.symbols = [self shuffleArray:self.symbols];
         [self changeKeyboardType:self.customAccessoryView.items[2] reset:YES];
     }
     

   • 點選右上角按鈕，切換鍵盤

     //更改鍵盤型別
     - (void)changeKeyboardType:(UIBarButtonItem *)item reset:(BOOL)isReset {
         self.secureKeyboardType = !isReset && self.secureKeyboardType == WMYSecureKeyboardTypeCharacter ? WMYSecureKeyboardTypeSymbol : WMYSecureKeyboardTypeCharacter;
         BOOL isSymbol = self.secureKeyboardType == WMYSecureKeyboardTypeSymbol;
         NSArray *keys = isSymbol ? self.symbols : [self.numbers arrayByAddingObjectsFromArray:self.letters];
         for (int i = 0; i < self.customInputView.subviews.count; i ++) {
             NSString *key = (keys.count - 1 < i) || [keys[i] isEqualToString:@"backspace"] || [keys[i] isEqualToString:@"uppercase"] ? @"" : keys[i];
             UIButton *keyButton = self.customInputView.subviews[i];
             if (i == 30) {//回退鍵
                 [self setupUppercaseButton:keyButton isKey:isSymbol];
                 [keyButton setTitle:isSymbol?key:@"" forState:UIControlStateNormal|UIControlStateSelected];
             } else if (i == 36) {//空格鍵
                 [self setupSpaceButton:keyButton isBig:isSymbol];
             } else if (i == 37) {//隱藏按鍵
                 CGRect frame = keyButton.frame;
                 frame.size = isSymbol ? CGSizeMake(0, 0) : CGSizeMake(self.keyWidth, self.keyHeight);
                 keyButton.frame = frame;
             }
             [keyButton setTitle:key forState:UIControlStateNormal];
         }
         item.title = isSymbol ? @"數字/字母" : @"符號";
     }
      
     

2. 洗牌演算法，交換第i個和之後的某一個元素

     - (NSArray *)shuffleArray:(NSArray *)items {
         NSMutableArray *newItems = [NSMutableArray arrayWithArray:items];
         for (int i = 0; i < newItems.count; i++) {
             int randomIndex = arc4random()%(newItems.count - i) + i;
             id item = newItems[randomIndex];
             //過濾控制字元，防止控制字元交換位置引起混亂
             if ([self.controls containsObject:item] || [self.controls containsObject:newItems[i]]) continue;
             newItems[randomIndex] = newItems[i];
             newItems[i] = item;
         }
         return newItems;
     }
   

3. 防截圖，通過UITextfield的安全輸入實現，將需要防截圖的區域的父檢視設定為下面的view，這裡設定為_customInputView = [self getSecureView];

     //防截圖
     - (UIView *)getSecureView{
         UITextField *bgTextField = [[UITextField alloc] init];
         [bgTextField setSecureTextEntry:YES];
   
         UIView *bgView = bgTextField.subviews.firstObject;
         [bgView setUserInteractionEnabled:YES];
         return bgView;
     }
   

4. 遇到的問題

   • 輸入之後，不會觸發UITextField的controlEvents事件；每次設定輸入之後，手動呼叫sendActionsForControlEvents方法，觸發事件
   • 控制字元在字元陣列中，隨機排序後，導致顯示混亂；通過過濾控制字元，不參與隨機排序解決
   • 按照mac鍵盤輸入所有字元，只有33個，少於字母和數字的36個；參考別的鍵盤，增加了€ ￡ ¥這三個符號

5. 待完善內容

   • 還有單獨數字輸入的鍵盤，由於時間不夠，暫時沒寫
   • 點選按鍵放大動畫，因為時間問題，還沒實現

6. 參考連結

   • iOS防截圖-完全解決
   • iconfont圖示
   • iOS安全鍵盤
   • UITextField的inputView和inputAccessoryView注意點