adding-custom-messages-51d8589.md

Adding Custom Messages

You can use the securedExecution method to add and display custom messages.

Note:

This topic is relevant to SAP Fiori elements for OData V2. For information about SAP Fiori elements for OData V4, see Adding Custom Messages.

This concept for message handling is based on the SAPUI5 Messaging. For more information, see the API Reference for Messaging.

SAP Fiori elements provides the securedExecution method that starts a 'busy session'.

When a busy session starts, all transition messages are removed automatically, since the system assumes that they belong to previous user interaction.

When the busy session ends, all transition messages that have been collected by the Messaging are automatically displayed to the user in a well-defined way, based on the severity of the message. This applies to (transition) messages that have been pushed into the Messaging automatically (for example, because they come from the OData model), and also to transition messages that are pushed to the Messaging explicitly by way of application coding.

Sample Code:

onCustomButtonPressed: function(oEvent){
  var oSource = oEvent.getSource();
  var oModel = oSource.getModel();
  var sBindingPath = ...; // binding path to retrieve some information
  var fnFunction = function(){
    return new Promise(function(fnResolve, fnReject){
      oModel.read(sBindingPath, {
        success: function(oResponse){
          var oMessage = new sap.ui.core.message.Message({
            message: "We have received the following response: " + oResponse,
            persistent: true, // create message as transition message
            type: sap.ui.core.MessageType.Success
          });
          //"Messaging" required from module "sap/ui/core/Messaging";
          Messaging.addMessages(oMessage);
          fnResolve();
        },
        error: fnReject
    });  
  };
  var mParameters = {
        sActionLabel:  oSource.getText() // or "Your custom text" 
   };
  this.extensionAPI.securedExecution(fnFunction, mParameters);
} 

The sample code shows that a message is created as a transition message by setting the attribute persistent to true. This attribute describes the lifetime of this message from the perspective of the SAPUI5 Messaging. The lifecycle of transition messages is not relevant to the Messaging. This means that they are persisted until another agent deletes them from the Messaging. The SAP Fiori elements framework triggers the deletions, which effectively limits the lifetime of these messages.

The lifecycle of messages with the attribute persistent : false is controlled by the Messaging. This kind of message is automatically removed when the entity this message has been bound to is reloaded from the back end.

Tip:

The sActionLabelMessages. For a single transition info message, sActionLabel has no effect, since a message toast is shown.

In some cases, you may need to display messages, even though no asynchronous operation is executed. The following code snippet shows how you can display messages in such a scenario:

Sample Code:

onCustomButtonPressed: function(oEvent){
    var oSource = oEvent.getSource();
    var fnAddMessage = function(){
    return new Promise(function(fnResolve){
          var oMessage = new sap.ui.core.message.Message({
            message: "Custom button was pressed",
            persistent: true, // create message as transition message
            type: sap.ui.core.MessageType.Success
          });
          //"Messaging" required from module "sap/ui/core/Messaging";
          Messaging.addMessages(oMessage);
          fnResolve();
   });
};
var mParameters = {
      sActionLabel:  oSource.getText() // or "Your custom text" 
 };
this.extensionAPI.securedExecution(fnAddMessage, mParameters);
} 

Related Links

For more information on the securedExecution method, see Using the SecuredExecution Method and the API Reference for securedExecution.

For general information on messages, see Using Messages.