#814 fix MDL issues

- additional workarounds for Material Design Lite problems
- validation fixes

fixes #814

ng2-components/ng2-activiti-form/src/components/widgets/text/text.widget.ts

@@ -15,11 +15,10 @@
  * limitations under the License.
  */
 
-import { Component } from '@angular/core';
+import { Component, ElementRef } from '@angular/core';
 import { WidgetComponent } from './../widget.component';
 
 declare let __moduleName: string;
-declare var componentHandler;
 
 @Component({
     moduleId: __moduleName,
@@ -29,4 +28,25 @@ declare var componentHandler;
 })
 export class TextWidget extends WidgetComponent {
 
+    constructor(private elementRef: ElementRef) {
+        super();
+    }
+
+    setupMaterialComponents(componentHandler: any): boolean {
+        // workaround for MDL issues with dynamic components
+        if (componentHandler) {
+            componentHandler.upgradeAllRegistered();
+            if (this.elementRef && this.hasValue()) {
+                let el = this.elementRef.nativeElement;
+                let container = el.querySelector('.mdl-textfield');
+                if (container) {
+                    container.MaterialTextfield.change(this.field.value);
+                }
+            }
+
+            return true;
+        }
+        return false;
+    }
+
 }