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PORuby on Rails: Create a button if a row exists in db
 

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  1. PORuby on Rails: Create a button if a row exists in db
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    <p>I'm creating a twitter-copy (just to learn Rails). I have a users-page where all users are listed. Next to the username I want to create a button that says "follow" if you are not following this user and "unfollow" if you are.</p> <p>I have already done it in PHP and I thought i could do something similar in Rails, but I'm not sure how.</p> <p><strong>followBtn.php</strong> - included after every user.</p> <pre><code>$subsTable = new Table('Sub'); if($user != $currentUser) { $follows = $subsTable-&gt;checkFollow($currentUserID, $userID); if($follows) { echo "&lt;form action='src/php/main.php' autocomplete='on' method='post'&gt;"; echo "&lt;input type='hidden' name='page' value='unfollow'&gt;"; echo "&lt;input type='hidden' name='followID' value='$userID'&gt;"; echo "&lt;input type='submit' value='Unfollow' id='unfollowBtn'&gt;"; echo "&lt;/form&gt;"; } if(!$follows) { echo "&lt;form action='src/php/main.php' autocomplete='on' method='post'&gt;"; echo "&lt;input type='hidden' name='page' value='follow'&gt;"; echo "&lt;input type='hidden' name='followID' value='$userID'&gt;"; echo "&lt;input type='submit' value='Follow' id='followBtn'&gt;"; echo "&lt;/form&gt;"; } } </code></pre> <p><strong>Table.php</strong></p> <pre><code>public function checkFollow($user, $follower) { $table = (string)self::$table; $query = " SELECT * FROM $table WHERE $table.userID = '$user' AND $table.followID = '$follower' ;"; $database = Database::getInstance(); $result = $database-&gt;fetch_assoc($query); return $result; } </code></pre> <p>This is my Rails-code I've got so far. I know it's not working, but maybe it's not that much that is wrong.</p> <p><strong>index.html.erb</strong></p> <pre><code>&lt;h2&gt;All users&lt;/h2&gt; &lt;table&gt; &lt;tr&gt; &lt;th&gt;Username&lt;/th&gt; &lt;th&gt;Email&lt;/th&gt; &lt;/tr&gt; &lt;% @user.each do |u| %&gt; &lt;tr&gt; &lt;td&gt;&lt;%= u.username %&gt;&lt;/td&gt; &lt;td&gt;&lt;%= u.email %&gt;&lt;/td&gt; &lt;% if(u.username != @current_user.username) %&gt; &lt;% if @following %&gt; &lt;% @temp_user = u %&gt; &lt;%= form_for(:subscription, :url =&gt; { :controller =&gt; "subscriptions", :action =&gt; "unsubscribe" }) do |s| %&gt; &lt;%= s.hidden_field(:userID, :value =&gt; @current_user.id) %&gt; &lt;%= s.hidden_field(:followingID, :value =&gt; u.id) %&gt; &lt;td&gt;&lt;%= s.submit "Unsubscribe" %&gt;&lt;/td&gt; &lt;% end %&gt; &lt;% else %&gt; &lt;%= form_for(:subscription, :url =&gt; { :controller =&gt; "subscriptions", :action =&gt; "subscribe" }) do |s| %&gt; &lt;%= s.hidden_field(:userID, :value =&gt; @current_user.id) %&gt; &lt;%= s.hidden_field(:followingID, :value =&gt; u.id) %&gt; &lt;td&gt;&lt;%= s.submit "Subscribe" %&gt;&lt;/td&gt; &lt;% end %&gt; &lt;% end %&gt; &lt;% end %&gt; &lt;/tr&gt; &lt;% end %&gt; &lt;/table&gt; </code></pre> <p><strong>user_controller.rb</strong></p> <pre><code>class UsersController &lt; ApplicationController before_filter :save_login_state, :only =&gt; [:new, :create] def index @user = User.all @current_user = User.find session[:user_id] @following = true if Subscriptions.find_by_sql("SELECT * FROM subscriptions WHERE userID = '{@current_user.id}' AND followingID = '{@temp_user.id}';") end end </code></pre> <p><strong>Errors</strong></p> <pre><code>NameError in UsersController#index uninitialized constant UsersController::Subscriptions </code></pre>
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    1. USAlexander
    1. USAlexander
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    1. COWhat errors do you see?
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      1. PORuby on Rails: Create a button if a row exists in db
      1. USshishirmk
    2. COAdded the error. @shishirmk
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      1. PORuby on Rails: Create a button if a row exists in db
      1. USAlexander
 

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