New helper methods to call methods on view models

src/octoprint/static/js/app/helpers.js

@@ -635,3 +635,56 @@ function getOnlyChangedData(data, oldData) {
     return f(data, oldData);
 }
 
+function callViewModels(allViewModels, method, callback) {
+    callViewModelsIf(allViewModels, method, undefined, callback);
+}
+
+function callViewModelsIf(allViewModels, method, condition, callback) {
+    if (condition == undefined || !_.isFunction(condition)) {
+        condition = function() { return true; };
+    }
+
+    var parameters = undefined;
+    if (!_.isFunction(callback)) {
+        // if callback is not a function that means we are supposed to directly
+        // call the view model method instead of providing it to the callback
+        // - let's figure out how
+
+        if (callback == undefined) {
+            // directly call view model method with no parameters
+            parameters = undefined;
+            log.debug("Calling method", method, "on view models");
+        } else if (_.isArray(callback)) {
+            // directly call view model method with these parameters
+            parameters = callback;
+            log.debug("Calling method", method, "on view models with specified parameters", parameters);
+        } else {
+            // ok, this doesn't make sense, callback is neither undefined nor
+            // an array, we'll return without doing anything
+            return;
+        }
+
+        // we reset this here so we now further down that we want to call
+        // the method directly
+        callback = undefined;
+    } else {
+        log.debug("Providing method", method, "on view models to specified callback", callback);
+    }
+
+    _.each(allViewModels, function(viewModel) {
+        if (viewModel.hasOwnProperty(method) && condition(viewModel, method)) {
+            if (callback == undefined) {
+                if (parameters != undefined) {
+                    // call the method with the provided parameters
+                    viewModel[method].apply(viewModel, parameters);
+                } else {
+                    // call the method without parameters
+                    viewModel[method]();
+                }
+            } else {
+                // provide the method to the callback
+                callback(viewModel[method]);
+            }
+        }
+    });
+}