fix: Avoid processing value change event due writing back of converte…

…d value (#12183) (CP: 2.7) (#12338)
vaadin · Nov 11, 2021 · 868d08a · 868d08a
1 parent e530e5a
commit 868d08a
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Showing 2 changed files with 34 additions and 1 deletion.
diff --git a/flow-data/src/main/java/com/vaadin/flow/data/binder/Binder.java b/flow-data/src/main/java/com/vaadin/flow/data/binder/Binder.java
@@ -1088,6 +1088,7 @@ protected static class BindingImpl<BEAN, FIELDVALUE, TARGET>
 
         private Registration onValueChange;
         private boolean valueInit = false;
+        private boolean convertedBack = false;
 
         /**
          * Contains all converters and validators chained together in the
@@ -1267,7 +1268,8 @@ private FIELDVALUE convertToFieldType(TARGET target) {
         private void handleFieldValueChange(
                 ValueChangeEvent<FIELDVALUE> event) {
             // Don't handle change events when setting initial value
-            if (valueInit) {
+            if (valueInit || convertedBack) {
+                convertedBack = false;
                 return;
             }
 
@@ -1295,6 +1297,7 @@ private BindingValidationStatus<TARGET> writeFieldValue(BEAN bean) {
                     if (convertBackToPresentation && value != null) {
                         FIELDVALUE converted = convertToFieldType(value);
                         if (!Objects.equals(field.getValue(), converted)) {
+                            convertedBack = true;
                             getField().setValue(converted);
                         }
                     }

diff --git a/flow-data/src/test/java/com/vaadin/flow/data/binder/BinderTest.java b/flow-data/src/test/java/com/vaadin/flow/data/binder/BinderTest.java
@@ -46,6 +46,7 @@
 import com.vaadin.flow.data.binder.testcomponents.TestTextField;
 import com.vaadin.flow.data.converter.Converter;
 import com.vaadin.flow.data.converter.StringToBigDecimalConverter;
+import com.vaadin.flow.data.converter.StringToDoubleConverter;
 import com.vaadin.flow.data.converter.StringToIntegerConverter;
 import com.vaadin.flow.data.validator.IntegerRangeValidator;
 import com.vaadin.flow.data.validator.NotEmptyValidator;
@@ -1683,6 +1684,35 @@ public void invalidUsage_modifyFieldsInsideValidator_binderDoesNotThrow() {
         Assert.assertTrue(validatorIsExecuted.get());
     }
 
+    @Test
+    public void validationShouldNotRunTwice() {
+        TestTextField salaryField = new TestTextField();
+        AtomicInteger count = new AtomicInteger(0);
+        item.setSalaryDouble(100d);
+        binder.forField(salaryField)
+                .withConverter(new StringToDoubleConverter(""))
+                .bind(Person::getSalaryDouble, Person::setSalaryDouble);
+        binder.setBean(item);
+        binder.addValueChangeListener(event -> {
+            count.incrementAndGet();
+        });
+
+        salaryField.setValue("1000");
+        assertTrue(binder.isValid());
+        assertEquals(1, count.get());
+
+        salaryField.setValue("salary");
+        assertFalse(binder.isValid());
+        assertEquals(2, count.get());
+
+        salaryField.setValue("2000");
+
+        // Without fix for #12356 count will be 5
+        assertEquals(3, count.get());
+
+        assertEquals(new Double(2000), item.getSalaryDouble());
+    }
+
     @Test
     public void setValidationErrorHandler_handlerIsSet_handlerMethodsAreCalled() {
         TestTextField testField = new TestTextField();