From f0d381ac081f7068ae917846181f431568e03197 Mon Sep 17 00:00:00 2001
From: Jarrett Croll <jarrett.croll@gmail.com>
Date: Thu, 30 Apr 2020 15:05:33 -0400
Subject: [PATCH] Set Error State Matcher from Control Model

---
 README.md                                     | 11 ++++++++++
 .../dynamic-form-validation.service.ts        | 20 +++++++++++--------
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index 282107a39..ec4b2c218 100644
--- a/README.md
+++ b/README.md
@@ -1071,6 +1071,17 @@ export const DEFAULT_ERROR_STATE_MATCHER: DynamicErrorMessagesMatcher =
     };
 ```
 
+You can also set an error matcher on a per control basis by assigning it under the `additional` field:
+```ts
+new DynamicInputModel({
+    id: "sampleInput",
+    label: "Sample Input",
+    additional: {
+        errorStateMatcher: myCustomErrorMessagesMatcher
+    }
+})
+```
+
 Please note here that NG Dynamic Forms always assumes both the control being invalid and error messages being defined on the model 
 as a fixed precondition.
 
diff --git a/projects/ng-dynamic-forms/core/src/lib/service/dynamic-form-validation.service.ts b/projects/ng-dynamic-forms/core/src/lib/service/dynamic-form-validation.service.ts
index 410c57d12..ab3e7793a 100644
--- a/projects/ng-dynamic-forms/core/src/lib/service/dynamic-form-validation.service.ts
+++ b/projects/ng-dynamic-forms/core/src/lib/service/dynamic-form-validation.service.ts
@@ -136,14 +136,18 @@ export class DynamicFormValidationService {
         control.updateValueAndValidity();
     }
 
-    showErrorMessages(control: AbstractControl, model: DynamicFormControlModel, hasFocus: boolean): boolean {
-
-        const precondition = control.invalid && model.hasErrorMessages;
-        const matcher = this._DYNAMIC_ERROR_MESSAGES_MATCHER ? this._DYNAMIC_ERROR_MESSAGES_MATCHER(control, model, hasFocus) :
-            DEFAULT_ERROR_STATE_MATCHER(control, model, hasFocus);
-
-        return precondition && matcher;
-    }
+  showErrorMessages(control: AbstractControl, model: DynamicFormControlModel, hasFocus: boolean): boolean {
+    const precondition = control.invalid && model.hasErrorMessages;
+
+    const matcher =
+      typeof model["getAdditional"] !== undefined && model["getAdditional"]("errorStateMatcher")
+        ? model["getAdditional"]("errorStateMatcher")
+        : this._DYNAMIC_ERROR_MESSAGES_MATCHER
+        ? this._DYNAMIC_ERROR_MESSAGES_MATCHER
+        : DEFAULT_ERROR_STATE_MATCHER;
+
+    return precondition && matcher(control, model, hasFocus);
+  }
 
     parseErrorMessageConfig(template: string, model: DynamicFormControlModel, error: any = null): string {