dialog 刘海屏、水滴屏、全面屏 全屏显示

// 关键代码
Window window = dialog.getWindow();
        if (window != null) {
            window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
            window.getDecorView().setPadding(0, 0, 0, 0);
            window.getDecorView().setBackgroundColor(Color.WHITE);
            WindowManager.LayoutParams layoutParams = window.getAttributes();
            layoutParams.width = WindowManager.LayoutParams.MATCH_PARENT;
            layoutParams.height = WindowManager.LayoutParams.MATCH_PARENT;
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
                // 延伸显示区域到刘海
                WindowManager.LayoutParams lp = window.getAttributes();
                lp.layoutInDisplayCutoutMode = WindowManager.LayoutParams.LAYOUT_IN_DISPLAY_CUTOUT_MODE_SHORT_EDGES;
                window.setAttributes(lp);
                // 设置页面全屏显示
                final View decorView = window.getDecorView();
                decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN | View.SYSTEM_UI_FLAG_LAYOUT_STABLE);
            }
            window.setAttributes(layoutParams);
        }