使用MMDrawerController的侧面抽屉push页面

最近开发中的一个需求是将以前UITabBarController管理的页面结构，改成抽屉效果，所以我就使用了MMDrawerController这个开源框架，github地址：https://github.com/mutualmobile/MMDrawerController。
　　MMDrawerController具体的用法这里就不详细说了，大家可以参考 这篇文章-iOS-MMDrawerController的使用。我们现在的需求是左侧抽屉打开后点击上面的按钮push出下一个页面，当这个push出来的页面pop回来以后左侧抽屉仍然保持打开的状态。

简单集成后的效果.gif

　　上图这样显然不是想要的效果。push出的页面应该从屏幕的边缘出现才对嘛！就像下图这样：

想要的效果.gif
　　我想到的思路是当点击PUSH按钮的时候，将当前屏幕截图，然后添加到左边抽屉的View上，同时调整抽屉的maximumLeftDrawerWidth为屏幕的宽度并取消阴影。在左侧控制器的- (void)viewDidAppear:(BOOL)animated方法中移除截屏图片，并且将maximumLeftDrawerWidth恢复为初始宽度并恢复显示阴影，这样pop回来以后页面看起来就跟push前一样了。

/// 添加当前页面的截屏
- (void)addCurrentPageScreenshot {
    
    UIImage *screenImage = [UIImage screenshot];
    UIImageView *imgView = [[UIImageView alloc] initWithImage:screenImage];
    imgView.image = screenImage;
    [self.view addSubview:imgView];
    self.coverImageView = imgView;
    
}

/// 设置抽屉视图pop后的状态
- (void)settingDrawerWhenPop {
    
    self.mm_drawerController.maximumLeftDrawerWidth = [UIScreen mainScreen].bounds.size.width - 50;
    self.mm_drawerController.showsShadow = YES;
    self.mm_drawerController.closeDrawerGestureModeMask = MMCloseDrawerGestureModeAll;
    [self.coverImageView removeFromSuperview];
    self.coverImageView = nil;
    
}

/// 设置抽屉视图push后的状态
- (void)settingDrawerWhenPush {
    
    [self.mm_drawerController setMaximumLeftDrawerWidth:[UIScreen mainScreen].bounds.size.width];
    self.mm_drawerController.showsShadow = NO;
    // 这里一定要关闭手势，否则隐藏在屏幕右侧的drawer可以被拖拽出来
    self.mm_drawerController.closeDrawerGestureModeMask = MMCloseDrawerGestureModeNone;
    
}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    
    [self settingDrawerWhenPop];
}

- (void)gotoSetting:(UIButton *)sender {
    
    [self addCurrentPageScreenshot];
    [self settingDrawerWhenPush];
    
    SettingViewController *settingVc = [[SettingViewController alloc] init];
    [self.navigationController pushViewController:settingVc animated:YES];
}

**-- 顺便贴出截屏的方法 -- **

#import "UIImage+Extension.h"

@implementation UIImage (Extension)

/// 截屏
+ (UIImage *)screenshot {
    
    CGSize imageSize = [[UIScreen mainScreen] bounds].size;
    
    UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);
    
    
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    for (UIWindow *window in [[UIApplication sharedApplication] windows]) {
        if (![window respondsToSelector:@selector(screen)] || [window screen] == [UIScreen mainScreen]) {
            CGContextSaveGState(context);
            
            CGContextTranslateCTM(context, [window center].x, [window center].y);
            
            CGContextConcatCTM(context, [window transform]);
            
            CGContextTranslateCTM(context,
                                  -[window bounds].size.width * [[window layer] anchorPoint].x,
                                  -[window bounds].size.height * [[window layer] anchorPoint].y);
            
            [[window layer] renderInContext:context];
            
            CGContextRestoreGState(context);
        }
    }
    
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    
    return image;
}

@end

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如果各位有其他方法或者思路，一起讨论一下吧！
Demo代码在这里https://github.com/yzxcool123/MMDrawerController-Demo.git