Question

基本上每次页面加载此错误都会在终端中弹出。它似乎没有引起任何实际问题：

NoMethodError (undefined method `each' for nil:NilClass): app/controllers/habits_controller.rb:8:in `sort'

我想解决这个问题，但我总体上知道如何解决这个问题。

当创建新习惯而不是:order默认为nil时，它应默认为下一个最高整数。

HabitsController

  def sort 
    params[:order].each do |id, order| 
    Habit.where(id: id).update_all(order: order) 
  end 
    render nothing: true 
  end

  def habit_params
    params.require(:habit).permit(
      :user_id, 
      :trigger,
      :tag_list,
      :current_level,
      :conceal,
      :missed_days,
      :target, 
      :reward,
      :comment,
      :commentable,
      :like,
      :likeable,
      :action,
      :order,
      :date_started,
      :missed_one,
      :completed,
      :completed_at,
      :notes_text,
      :notes_date, 
      :notable, 
      :note, 
      :committed => [],
      levels_attributes: [
      :missed_days,
      :days_lost], notes_attributes: [:notable, :note, :notes_text, :notes_date, :_destroy])
  end

模式

create_table "habits", force: true do |t|
  t.integer  "order"
end

rails c

[2] pry(main)> Habit.last
  Habit Load (2.9ms)  SELECT  "habits".* FROM "habits"  ORDER BY "habits"."id" DESC LIMIT 1
=> #<Habit:0x007f94e0da39b0
 id: 12,
 missed_days: 0,
 conceal: false,
 likes: nil,
 date_started: Tue, 15 Sep 2015 00:00:00 EDT -04:00,
 trigger: "wake up",
 action: "run",
 target: "2 miles",
 reward: "eat dessert",
 user_id: 2,
 created_at: Tue, 15 Sep 2015 09:53:31 EDT -04:00,
 updated_at: Tue, 15 Sep 2015 09:53:31 EDT -04:00,
 order: nil,
 completed_at: nil,
 committed: ["sun", "mon", "tue", "wed", "thu", "fri", "sat", ""],
 strike_date: nil,
 missed_days_date: nil>

rails s

Started POST "/habits/sort" for 127.0.0.1 at 2015-09-15 10:02:36 -0400
Processing by HabitsController#sort as */*
  User Load (2.4ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 2]]
  Habit Load (0.4ms)  SELECT "habits".* FROM "habits" WHERE "habits"."user_id" = $1  [["user_id", 2]]
  ActsAsTaggableOn::Tag Load (0.5ms)  SELECT "tags".* FROM "tags" WHERE (LOWER(name) = LOWER('ingrain'))
  CACHE (0.0ms)  SELECT "habits".* FROM "habits" WHERE "habits"."user_id" = $1  [["user_id", 2]]
  Level Load (0.3ms)  SELECT "levels".* FROM "levels" WHERE "levels"."habit_id" = $1  ORDER BY "levels"."id" ASC  [["habit_id", 11]]
  Level Load (0.3ms)  SELECT "levels".* FROM "levels" WHERE "levels"."habit_id" = $1  ORDER BY "levels"."id" ASC  [["habit_id", 12]]
  Level Load (0.3ms)  SELECT "levels".* FROM "levels" WHERE "levels"."habit_id" = $1  ORDER BY "levels"."id" ASC  [["habit_id", 10]]
  ActsAsTaggableOn::Tag Load (0.3ms)  SELECT  DISTINCT "tags".* FROM "tags" INNER JOIN "taggings" ON "tags"."id" = "taggings"."tag_id" WHERE "taggings"."tagger_id" = $1 AND "taggings"."tagger_type" = $2  ORDER BY taggings_count desc LIMIT 20  [["tagger_id", 2], ["tagger_type", "User"]]
   (0.3ms)  SELECT COUNT(*) FROM "habits" WHERE "habits"."user_id" = $1  [["user_id", 2]]
Completed 500 Internal Server Error in 51ms

NoMethodError (undefined method `each' for nil:NilClass): app/controllers/habits_controller.rb:8:in `sort'

习惯-sort.js

var update_orders, update_remote_orders; 

update_remote_orders = function(orders) { 
return $.ajax({ 
url: "/habits/sort", 
type: "POST", 
data: { 
order: orders 
}, 
success: function(data) {} 
}); 
}; 

update_orders = function() { 
var orders; 
orders = {}; 
$("#sortable tr input.order:hidden").each(function(i, o) { 
orders[$(o).attr("data-id")] = i; 
return $(o).val(i); 
}); 
return update_remote_orders(orders); 
}; 

$(document).ready(function() { 
update_orders(); 
$("#sortable").sortable({ 
axis: 'y', 
handle: ".btn", 
stop: function(ui, event) { 
return update_orders(); 
} 
}); 
});

如何排序：订购零？

0 个答案: