最近在新的項目中遇到的下面幾個問題：

• 項目中需要實現類似閑魚的發布凸出按鈕;

沒有自定義tabbar,只是子類化了tabbar

1.設置imageInsets

//     設置圖片和文字之間的間
    if ([title isEqualToString:@"發布"]) {
        controller.tabBarItem.imageInsets = UIEdgeInsetsMake(-20, 0, 10, 0);
        controller.tabBarItem.titlePositionAdjustment = UIOffsetMake(0, -2);
    }else{
        controller.tabBarItem.imageInsets = UIEdgeInsetsMake(-3, 0, 3, 0);
        controller.tabBarItem.titlePositionAdjustment = UIOffsetMake(0, -2);
    }

2.在tabbar子類中設置背景圖片

- (void)layoutSubviews{
    [super layoutSubviews];
    Class class = NSClassFromString(@"UITabBarButton");
    int btnIndex = 0;
    for (UIView *btn in self.subviews){
        if ([btn isKindOfClass:class]) {
            if (btnIndex == 2) { // btnIndex == 2 的時候， 為中間按鈕， 添加一個背景圖片
                self.imageView.frame = CGRectMake((btn.width-65)*0.5, -27, 65, btn.height + 10);//CGRectMake(5, -17, btn.lj_width - 10, btn.lj_height + 17)
                
                [btn insertSubview:self.imageView atIndex:0];
                self.btn = btn;
            }
            btnIndex++;
        }
    }
}

3.點擊范圍的設置

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
    if (self.isHidden == NO) {
        CGPoint newP = [self convertPoint:point toView:self.imageView];
        //判斷如果這個新的點是在發布按鈕身上，那么處理點擊事件最合適的view就是發布按鈕
        if ( [self.imageView pointInside:newP withEvent:event]) {
            return self.btn;
        }else{ //如果點不在發布按鈕身上，直接讓系統處理就可以了
            return [super hitTest:point withEvent:event];
        }
    }
    else {  //tabbar隱藏了，那么說明已經push到其他的頁面了，這個時候還是讓系統去判斷最合適的view處理就好了
        return [super hitTest:point withEvent:event];
    }
}

• iOS13tarbbar默認文字顏色無法設置
  下面的代碼導致的

// 設置樣式, 去除tabbar上面的黑線
self.barStyle = UIBarStyleBlack;

1.設置文字顏色

// 設置 tabbarItem 選中狀態下的文字顏色(不被系統默認渲染,顯示文字自定義顏色)
    NSDictionary *normalDic = [NSDictionary dictionaryWithObject:[AppConfigModel getColor:@"#999696"] forKey:NSForegroundColorAttributeName];
    [controller.tabBarItem setTitleTextAttributes:normalDic forState:UIControlStateNormal];
    NSDictionary *selectedDic = [NSDictionary dictionaryWithObject:[AppConfigModel obtainThemeColor] forKey:NSForegroundColorAttributeName];
    [controller.tabBarItem setTitleTextAttributes:selectedDic forState:UIControlStateSelected];

2.創建其他方法去除tabbar上面的黑線

- (void)removiewTopline{
    
    CGRect rect = CGRectMake(0, 0, [AppConfigModel obtainAllScreenWidth], [AppConfigModel obtainAllScreenHeight]);
    UIGraphicsBeginImageContext(rect.size);

    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, [[UIColor clearColor] CGColor]);

    CGContextFillRect(context, rect);

    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();
    [self setShadowImage:img];
}

• iOS13 頁面跳轉后tabbar選擇顏色變成了默認藍色

在tabbar子類- (void)layoutSubviews方法中增加

self.tintColor =selectColor;