Edit in JSFiddle

   <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>

  
<div ng-app="myApp" ng-controller="myCtrl">
<h3>Görev Listem</h3>
 <table border="1" cellpadding="5">
  <thead>
	 <tr>
	   <th>No</th>
	   <th>Görev</th>
	   <th>Gün</th>
	   <th>Durum</th>
	   <th>İşlem</th>
	 </tr>
  </thead>
  <tbody>
    <tr ng-repeat="item in items">
          <td ng-show="isSelected(item)">{{$index + 1}}</td>
	      <td ng-show="isSelected(item)"><input type="text" placeholder="Görev..." ng-model="EditingItem.gorev"/></td>
	      <td ng-show="isSelected(item)">
		  <select ng-model="EditingItem.gun">
		    <option>Pazartesi</option>
		    <option>Salı</option>
		    <option>Çarşamba</option>		   
		    <option>Perşembe</option>		   
		    <option>Cuma</option>		   
		    <option>Cumartesi</option>		   
		    <option>Pazar</option>		   		   
	       </select>
		  </td>
	      <td ng-show="isSelected(item)">
	       <select ng-model="EditingItem.durum">
		    <option>Tamamlanmadı</option>
		    <option>Devam Ediyor</option>
		    <option>Tamamlandı</option>		   
	       </select>			  
		  </td>
	      <td ng-show="isSelected(item)">
	       <button ng-click="SaveFunction(EditingItem, $index)">Kaydet</button>
	       <button ng-click="CancelFunction()">İptal</button>
	      </td>	
		  
          <td ng-if="!isSelected(item)">{{$index + 1}}</td>
	      <td ng-if="!isSelected(item)">{{ item.gorev }}</td>
	      <td ng-if="!isSelected(item)">{{ item.gun }}</td>
	      <td ng-if="!isSelected(item)">{{ item.durum }}</td>
	      <td ng-if="!isSelected(item)">
	       <button ng-click="EditFunction(item)">Düzenle</button>
	       <button ng-click="RemoveFunction($index)">x Kaldır</button>
	      </td>	
     </tr>
	 
	

	<tr>
	   <td></td>
	   <td><input type="text" placeholder="Görev..." ng-model="newItem.baslik"/></td>
	   <td>
	     <select ng-model="newItem.gun">
		   <option>Pazartesi</option>
		   <option>Salı</option>
		   <option>Çarşamba</option>		   
		   <option>Perşembe</option>		   
		   <option>Cuma</option>		   
		   <option>Cumartesi</option>		   
		   <option>Pazar</option>		   		   
	     </select>
	   </td>
	   <td>
	     <select ng-model="newItem.durum">
		   <option>Tamamlanmadı</option>
		   <option>Devam Ediyor</option>
		   <option>Tamamlandı</option>		   
	     </select>	   
	   </td>
	  <td><button ng-click="AddFunction(newItem)">+ Ekle</button></td>	
	</tr>
  </tbody>
 </table>
</div>

<script>
   var app = angular.module("myApp", []);
   app.controller("myCtrl", function($scope) {
    $scope.items = [
                   {gorev:'AngularJS dersleri izlenecek',gun:'Pazartesi', durum:'Tamamlanmadı'},
                   {gorev:'E-Ticaret projesi teslim edilecek',gun:'Cumartesi', durum:'Devam Ediyor'},
                   {gorev:'Bankaya para yatırılacak',gun:'Pazar', durum:'Tamamlandı'}];
    $scope.AddFunction = function(item) {
     $scope.items.push({gorev:item.baslik, gun:item.gun, durum:item.durum});
	 item.baslik = ""; item.gun = ""; item.durum = "";
    };
	$scope.SaveFunction = function(item, index){
	  $scope.items[index] = {gorev:item.gorev, gun:item.gun, durum:item.durum};
    }
	$scope.RemoveFunction = function(index) {
     $scope.items.splice(index, 1);
    };
    $scope.isSelected = function(row){
	  if(row == undefined) return false;
      return $scope.selected_row===row;
    }
	$scope.EditFunction = function(row){
	    $scope.EditingItem = row;
		$scope.selected_row=row;
    }
	$scope.CancelFunction = function(row){
		$scope.selected_row=null;
    }	
   });

</script>