Merge pull request #1027 from yast/cwm/restore_richtext_scroll

Restore the CWM::RichText scroll after updating its content

library/cwm/src/lib/cwm/common_widgets.rb

@@ -365,6 +365,47 @@ class RichText < AbstractWidget
     self.widget_type = :richtext
 
     include ValueBasedWidget
+
+    # Determines if the vertical scroll must be kept after updating the content
+    #
+    # @note Useful only to keep the sense of continuity when redrawing basically with the same text
+    #
+    # Keeping the vertical scroll after changing the value is mostly intended to be used after a
+    # redraw because of a user action. However, using it after changing the content noticeably
+    # (e.g., displaying different product descriptions), will look like a randomly positioned
+    # vertical scroll.
+    #
+    # @return [Boolean] true if the vertical scroll must be kept; false otherwise
+    def keep_scroll?
+      false
+    end
+
+    # Updates the content
+    #
+    # Depending on #keep_scroll?, the vertical scroll will be saved and restored.
+    #
+    # @param val [String] the new content for the widget
+    def value=(val)
+      current_vscroll = vscroll
+      super
+      self.vscroll = current_vscroll if keep_scroll?
+    end
+
+  private
+
+    # Saves the current vertical scroll
+    #
+    # @return [String] current vertical scroll value
+    def vscroll
+      Yast::UI.QueryWidget(Id(widget_id), :VScrollValue)
+    end
+
+    # Sets vertical scroll
+    #
+    # @param value [String] the new vertical scroll value
+    def vscroll=(value)
+      Yast::UI.ChangeWidget(Id(widget_id), :VScrollValue, value)
+    end
   end
 
   # Time field widget

library/cwm/test/common_widgets_test.rb

@@ -6,7 +6,6 @@
 require "cwm/rspec"
 
 describe CWM::RadioButtons do
-
   class TestRadioButtons < CWM::RadioButtons
     def label
       "Choose a number"
@@ -59,3 +58,55 @@ def hspacing
     end
   end
 end
+
+describe CWM::RichText do
+  subject { described_class.new }
+  let(:widget_id) { Id(subject.widget_id) }
+  let(:new_content) { "Updated content" }
+  let(:vscroll) { "40" }
+
+  describe "#value=" do
+    before do
+      allow(Yast::UI).to receive(:QueryWidget).with(widget_id, :VScrollValue).and_return(vscroll)
+      allow(Yast::UI).to receive(:ChangeWidget)
+    end
+
+    context "when set to keep the scroll" do
+      before do
+        allow(subject).to receive(:keep_scroll?).and_return(true)
+      end
+
+      it "changes the widget value" do
+        expect(Yast::UI).to receive(:ChangeWidget).with(widget_id, :Value, new_content)
+
+        subject.value = new_content
+      end
+
+      it "saves vertical scroll position" do
+        expect(Yast::UI).to receive(:QueryWidget).with(widget_id, :VScrollValue)
+
+        subject.value = new_content
+      end
+
+      it "restores vertical scroll" do
+        expect(Yast::UI).to receive(:ChangeWidget).with(widget_id, :VScrollValue, vscroll)
+
+        subject.value = new_content
+      end
+    end
+
+    context "when set to not keep the scroll" do
+      it "changes the widget value" do
+        expect(Yast::UI).to receive(:ChangeWidget).with(widget_id, :Value, new_content)
+
+        subject.value = new_content
+      end
+
+      it "does not restore the scroll" do
+        expect(Yast::UI).to_not receive(:ChangeWidget).with(widget_id, :VScrollValue, anything)
+
+        subject.value = new_content
+      end
+    end
+  end
+end

package/yast2.changes

@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Fri Mar  6 13:26:57 UTC 2020 - David Diaz <dgonzalez@suse.com>
+
+- Allow to restore the vertical scroll of a CWM::RichText
+  (related to bsc#1049965)
+- 4.2.70
+
 -------------------------------------------------------------------
 Fri Mar  6 12:00:43 UTC 2020 - David Diaz <dgonzalez@suse.com>
 

package/yast2.spec

@@ -17,7 +17,7 @@
 
 
 Name:           yast2
-Version:        4.2.69
+Version:        4.2.70
 Release:        0
 Summary:        YaST2 Main Package
 License:        GPL-2.0-only