widget.Form: implement Disableable

Allow disabling and re-enabling a form. Resolves fyne-io#2157.
lunarforge · Apr 15, 2021 · e99b4c0 · e99b4c0
1 parent 2deba2b
commit e99b4c0
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Showing 10 changed files with 100 additions and 1 deletion.
diff --git a/widget/form.go b/widget/form.go
@@ -52,6 +52,8 @@ type Form struct {
 	buttonBox    *fyne.Container
 	cancelButton *Button
 	submitButton *Button
+
+	disabled bool
 }
 
 // Append adds a new row to the form, using the text as a label next to the specified Widget
@@ -89,6 +91,33 @@ func (f *Form) Refresh() {
 	canvas.Refresh(f.super()) // refresh ourselves for BG color - the above updates the content
 }
 
+// Enable enables submitting this form.
+//
+// Since: 2.1
+func (f *Form) Enable() {
+	f.disabled = false
+	f.cancelButton.Enable()
+	f.checkValidation(nil) // as the form may be invalid
+}
+
+// Disable disables submitting this form.
+//
+// Since: 2.1
+func (f *Form) Disable() {
+	f.disabled = true
+	f.submitButton.Disable()
+	f.cancelButton.Disable()
+}
+
+// Disabled returns whether submitting the form is disabled.
+// Note that, if the form fails validation, the submit button may be
+// disabled even if this method returns true.
+//
+// Since: 2.1
+func (f *Form) Disabled() bool {
+	return f.disabled
+}
+
 func (f *Form) createInput(item *FormItem) fyne.CanvasObject {
 	_, ok := item.Widget.(fyne.Validatable)
 	if item.HintText == "" {
@@ -155,7 +184,9 @@ func (f *Form) checkValidation(err error) {
 		}
 	}
 
-	f.submitButton.Enable()
+	if !f.disabled {
+		f.submitButton.Enable()
+	}
 }
 
 func (f *Form) setUpValidation(widget fyne.CanvasObject, i int) {

diff --git a/widget/form_test.go b/widget/form_test.go
@@ -232,3 +232,71 @@ func TestForm_EntryValidation_FirstTypeValid(t *testing.T) {
 
 	test.AssertImageMatches(t, "form/validation_entry_first_type_invalid.png", w.Canvas().Capture())
 }
+
+func TestForm_DisableEnable(t *testing.T) {
+	app := test.NewApp()
+	defer test.NewApp()
+	app.Settings().SetTheme(theme.LightTheme())
+
+	form := &Form{
+		Items: []*FormItem{
+			{Text: "test1", Widget: NewEntry()},
+		},
+		OnSubmit: func() {}, OnCancel: func() {}}
+	w := test.NewWindow(form)
+	defer w.Close()
+
+	if form.Disabled() {
+		t.Error("form.Disabled() returned true when it should have been false")
+	}
+
+	test.AssertImageMatches(t, "form/disable_initial.png", w.Canvas().Capture())
+
+	form.Disable()
+
+	if !form.Disabled() {
+		t.Error("form.Disabled() returned false when it should have been true")
+	}
+
+	test.AssertImageMatches(t, "form/disable_disabled.png", w.Canvas().Capture())
+
+	form.Enable()
+
+	if form.Disabled() {
+		t.Error("form.Disabled() returned true when it should have been false")
+	}
+
+	test.AssertImageMatches(t, "form/disable_re_enabled.png", w.Canvas().Capture())
+}
+
+func TestForm_Disable_Validation(t *testing.T) {
+	app := test.NewApp()
+	defer test.NewApp()
+	app.Settings().SetTheme(theme.LightTheme())
+
+	entry := &Entry{Validator: validation.NewRegexp(`^\d{2}-\w{4}$`, "Input is not valid"), Text: "wrong"}
+
+	form := &Form{Items: []*FormItem{{Text: "test", Widget: entry}}, OnSubmit: func() {}, OnCancel: func() {}}
+	w := test.NewWindow(form)
+	defer w.Close()
+
+	test.AssertImageMatches(t, "form/disable_validation_initial.png", w.Canvas().Capture())
+
+	form.Disable()
+
+	test.AssertImageMatches(t, "form/disable_validation_disabled_invalid.png", w.Canvas().Capture())
+
+	form.Enable()
+
+	test.AssertImageMatches(t, "form/disable_validation_enabled_invalid.png", w.Canvas().Capture())
+
+	entry.SetText("15-true")
+	test.AssertImageMatches(t, "form/disable_validation_enabled_valid.png", w.Canvas().Capture())
+
+	// ensure we don't re-enable the form when entering something valid
+	entry.SetText("invalid")
+	form.Disable()
+	entry.SetText("15-true")
+
+	test.AssertImageMatches(t, "form/disable_validation_disabled_valid.png", w.Canvas().Capture())
+}
diff --git a/widget/testdata/form/disable_disabled.png b/widget/testdata/form/disable_disabled.png
diff --git a/widget/testdata/form/disable_initial.png b/widget/testdata/form/disable_initial.png
diff --git a/widget/testdata/form/disable_re_enabled.png b/widget/testdata/form/disable_re_enabled.png
diff --git a/widget/testdata/form/disable_validation_disabled_invalid.png b/widget/testdata/form/disable_validation_disabled_invalid.png
diff --git a/widget/testdata/form/disable_validation_disabled_valid.png b/widget/testdata/form/disable_validation_disabled_valid.png
diff --git a/widget/testdata/form/disable_validation_enabled_invalid.png b/widget/testdata/form/disable_validation_enabled_invalid.png
diff --git a/widget/testdata/form/disable_validation_enabled_valid.png b/widget/testdata/form/disable_validation_enabled_valid.png
diff --git a/widget/testdata/form/disable_validation_initial.png b/widget/testdata/form/disable_validation_initial.png