how to remove "viewing read- only"

Hi kirank,

If you don't have an Editor or Admin access over that interface, then you can't edit it. Please add yourself/ask your system admin to add into the respective security group. 
docs.appian.com/.../interface_object.html

thanks Selvakumar Kumarasamy

i am just go back in app nd reopen the interface, it works.

For context, there is another reason (in addition to having only Viewer security) that can cause an object to display as read-only: if it is already being edited. This can occur if another user is editing or even if you are editing it within another browser window. 

In these cases you will usually see a message that it is currently being edited and you can decide whether to overwrite the edit or just view in read-only mode. 

I'm guessing that is what has happened in this case because when you went back to the interface, the other user (or you in another window) had likely stopped editing the object and released the lock.

=a!localVariables(
local!selectedCategory: null,
local!selectedItem: null,

/* Define options for the first dropdown */
local!categoryOptions: {
{ label: "Fruits", value: "fruits" },
{ label: "Vegetables", value: "vegetables" }
},

/* Define options for the second dropdown based on the selected category */
local!itemOptions: a!match(
value: local!selectedCategory,
equals: "fruits",
then: {
{ label: "Apple", value: "apple" },
{ label: "Banana", value: "banana" }
},
equals: "vegetables",
then: {
{ label: "Carrot", value: "carrot" },
{ label: "Broccoli", value: "broccoli" }
},
default: {}
),

1. a!formLayout(
   label: "Dependent Dropdowns Example",
   contents: {
   a!dropdownField(
   label: "Category",
   placeholderLabel: "Select a category",
   choiceLabels: a!forEach(
   items: local!categoryOptions,
   expression: fv!item.label
   ),
   choiceValues: a!forEach(
   items: local!categoryOptions,
   expression: fv!item.value
   ),
   value: local!selectedCategory,
   saveInto: local!selectedCategory,
   required: true
   ),
   a!dropdownField(
   label: "Item",
   placeholderLabel: "Select an item",
   choiceLabels: a!forEach(
   items: local!itemOptions,
   expression: fv!item.label
   ),
   choiceValues: a!forEach(
   items: local!itemOptions,
   expression: fv!item.value
   ),
   value: local!selectedItem,
   saveInto: local!selectedItem,
   required: true,
   disabled: a!isNullOrEmpty(local!selectedCategory)
   )
   },
   buttons: a!buttonLayout(
   primaryButtons: a!buttonWidget(
   label: "Submit",
   style: "PRIMARY",
   validate: true
   )
   )
   )
   )

=a!localVariables(
  local!selectedCategory: null,
  local!selectedItem: null,

  /* Define options for the first dropdown */
  local!categoryOptions: {
    { label: "Fruits", value: "fruits" },
    { label: "Vegetables", value: "vegetables" }
  },

  /* Define options for the second dropdown based on the selected category */
  local!itemOptions: a!match(
    value: local!selectedCategory,
    equals: "fruits",
    then: {
      { label: "Apple", value: "apple" },
      { label: "Banana", value: "banana" }
    },
    equals: "vegetables",
    then: {
      { label: "Carrot", value: "carrot" },
      { label: "Broccoli", value: "broccoli" }
    },
    default: {}
  ),

  a!formLayout(
    label: "Dependent Dropdowns Example",
    contents: {
      a!dropdownField(
        label: "Category",
        placeholderLabel: "Select a category",
        choiceLabels: a!forEach(
          items: local!categoryOptions,
          expression: fv!item.label
        ),
        choiceValues: a!forEach(
          items: local!categoryOptions,
          expression: fv!item.value
        ),
        value: local!selectedCategory,
        saveInto: local!selectedCategory,
        required: true
      ),
      a!dropdownField(
        label: "Item",
        placeholderLabel: "Select an item",
        choiceLabels: a!forEach(
          items: local!itemOptions,
          expression: fv!item.label
        ),
        choiceValues: a!forEach(
          items: local!itemOptions,
          expression: fv!item.value
        ),
        value: local!selectedItem,
        saveInto: local!selectedItem,
        required: true,
        disabled: a!isNullOrEmpty(local!selectedCategory)
      )
    },
    buttons: a!buttonLayout(
      primaryButtons: a!buttonWidget(
        label: "Submit",
        style: "PRIMARY",
        validate: true
      )
    )
  )
)