Lior Vernia has uploaded a new change for review.
Change subject: webadmin: Introducing AddRemoveRowWidget
......................................................................
webadmin: Introducing AddRemoveRowWidget
This is a reusable widget used to display a list of other widgets,
backed by a ListModel of values. Entries may be removed or added using
minus/plus buttons. A new entry is added by activating a semi-disabled
"ghost" entry.
Change-Id: I15958e4b7c1fcf0ec08ea35eb32c690964f2a366
Signed-off-by: Lior Vernia <lver...@redhat.com>
---
A
frontend/webadmin/modules/gwt-common/src/main/java/org/ovirt/engine/ui/common/widget/AddRemoveRowWidget.java
1 file changed, 227 insertions(+), 0 deletions(-)
git pull ssh://gerrit.ovirt.org:29418/ovirt-engine refs/changes/30/19530/1
diff --git
a/frontend/webadmin/modules/gwt-common/src/main/java/org/ovirt/engine/ui/common/widget/AddRemoveRowWidget.java
b/frontend/webadmin/modules/gwt-common/src/main/java/org/ovirt/engine/ui/common/widget/AddRemoveRowWidget.java
new file mode 100644
index 0000000..e5165db
--- /dev/null
+++
b/frontend/webadmin/modules/gwt-common/src/main/java/org/ovirt/engine/ui/common/widget/AddRemoveRowWidget.java
@@ -0,0 +1,227 @@
+package org.ovirt.engine.ui.common.widget;
+
+import java.util.ArrayList;
+import java.util.LinkedList;
+import java.util.List;
+
+import org.ovirt.engine.core.common.utils.Pair;
+import org.ovirt.engine.ui.common.CommonApplicationResources;
+import
org.ovirt.engine.ui.common.widget.uicommon.popup.AbstractModelBoundPopupWidget;
+import org.ovirt.engine.ui.uicommonweb.models.ListModel;
+import com.google.gwt.core.client.GWT;
+import com.google.gwt.event.dom.client.ClickEvent;
+import com.google.gwt.event.dom.client.ClickHandler;
+import com.google.gwt.event.logical.shared.HasValueChangeHandlers;
+import com.google.gwt.event.logical.shared.ValueChangeEvent;
+import com.google.gwt.event.logical.shared.ValueChangeHandler;
+import com.google.gwt.resources.client.CssResource;
+import com.google.gwt.uibinder.client.UiField;
+import com.google.gwt.user.client.ui.FlowPanel;
+import com.google.gwt.user.client.ui.HorizontalPanel;
+import com.google.gwt.user.client.ui.Image;
+import com.google.gwt.user.client.ui.Panel;
+import com.google.gwt.user.client.ui.PushButton;
+import com.google.gwt.user.client.ui.Widget;
+
+/**
+ * This model-backed widget may be used to display a list of values of type T,
where each value is display using a
+ * widget of type V. Existing values may be removed by pressing minus-signed
buttons located next to them, while new
+ * values may be added by pressing a plus-signed button located next to a
special "ghost" entry. This special entry is
+ * half-disabled, and only becomes enabled when its value is set to a valid
one; it will be overlooked when flushing.
+ *
+ * @param <M>
+ * the model backing this widget.
+ * @param <T>
+ * the type of the values contained in the backing model.
+ * @param <V>
+ * the type of widget used to display each value.
+ */
+public abstract class AddRemoveRowWidget<M extends ListModel, T, V extends
Widget & HasValueChangeHandlers<T>> extends AbstractModelBoundPopupWidget<M> {
+
+ public interface WidgetStyle extends CssResource {
+ String entryStyle();
+ String buttonStyle();
+ }
+
+ @UiField
+ public FlowPanel contentPanel;
+
+ @UiField
+ public WidgetStyle style;
+
+ protected CommonApplicationResources resources =
GWT.create(CommonApplicationResources.class);
+
+ private final List<Pair<T, V>> items;
+
+ public AddRemoveRowWidget() {
+ items = new LinkedList<Pair<T, V>>();
+ }
+
+ protected void init(ListModel model) {
+ items.clear();
+ contentPanel.clear();
+ Iterable<T> values = model.getItems();
+ if (values != null) {
+ for (T value : values) {
+ addEntry(value);
+ }
+ }
+ addGhostEntry();
+ }
+
+ protected void flush(ListModel model) {
+ ArrayList<T> values = new ArrayList<T>();
+ for (Pair<T, V> item : items) {
+ T value = item.getFirst();
+ if (!isGhost(value)) {
+ values.add(value);
+ }
+ }
+ model.setItems(values);
+ }
+
+ private void addGhostEntry() {
+ addEntry(createGhostValue());
+ }
+
+ private void addEntry(T value) {
+ final HorizontalPanel entry = new HorizontalPanel();
+ entry.addStyleName(style.entryStyle());
+ contentPanel.add(entry);
+
+ final V widget = createWidget(value);
+ Pair<T, V> item = new Pair<T, V>(value, widget);
+ items.add(item);
+ entry.add(widget);
+
+ PushButton button = createButton(item);
+ entry.add(button);
+
+ final boolean ghost = isGhost(value);
+ toggleGhost(value, widget, ghost);
+ widget.addValueChangeHandler(new ValueChangeHandler<T>() {
+
+ private boolean wasGhost = ghost;
+
+ @Override
+ public void onValueChange(ValueChangeEvent<T> event) {
+ T value = event.getValue();
+ boolean becomingGhost = isGhost(value);
+ if (becomingGhost != wasGhost) {
+ ((PushButton) entry.getWidget(entry.getWidgetCount() -
1)).setEnabled(!becomingGhost);
+ toggleGhost(value, widget, becomingGhost);
+ wasGhost = becomingGhost;
+ }
+ }
+ });
+
+ onAdd(value, widget);
+ }
+
+ private void removeEntry(Pair<T, V> item) {
+ items.remove(item);
+ contentPanel.remove(item.getSecond().getParent());
+ onRemove(item.getFirst(), item.getSecond());
+ }
+
+ private void swapAddButton(Pair<T, V> item, PushButton addButton) {
+ Panel entry = (Panel) item.getSecond().getParent();
+ entry.remove(addButton);
+ entry.add(createButton(item));
+ }
+
+ private PushButton createButton(final Pair<T, V> item) {
+ boolean ghostItem = isGhost(item.getFirst());
+ final PushButton button =
+ new PushButton(new Image(ghostItem ? resources.increaseIcon()
: resources.decreaseIcon()));
+ button.addStyleName(style.buttonStyle());
+ button.setEnabled(!ghostItem);
+
+ button.addClickHandler(ghostItem ?
+ new ClickHandler() {
+
+ @Override
+ public void onClick(ClickEvent event) {
+ swapAddButton(item, button);
+ addGhostEntry();
+ }
+ } :
+ new ClickHandler() {
+
+ @Override
+ public void onClick(ClickEvent event) {
+ removeEntry(item);
+ }
+ });
+
+ return button;
+ }
+
+ /**
+ * This method is called straight after an entry is removed. Override to
specify implementation-specific behavior.
+ *
+ * @param value
+ * the value removed.
+ * @param widget
+ * the widget removed.
+ */
+ protected void onRemove(T value, V widget) {
+ // do nothing
+ }
+
+ /**
+ * This method is called straight after an entry is added. Override to
specify implementation-specific behavior.
+ *
+ * @param value
+ * the value added.
+ * @param widget
+ * the widget added.
+ */
+ protected void onAdd(T value, V widget) {
+ // do nothing
+ }
+
+ /**
+ * This method should return a new widget of type V backed by a value of
type T.
+ *
+ * @param value
+ * the value backing the widget.
+ * @return a newly-constructed widget of type V.
+ */
+ protected abstract V createWidget(T value);
+
+ /**
+ * This method should manufacture a new object of type T, corresponding to
a "ghost" entry as implemented by a
+ * specific subclass. This object should be distinct from regular values,
so that the entry could not be mistaken
+ * for a regular entry.
+ *
+ * @return a value corresponding to a ghost entry.
+ */
+ protected abstract T createGhostValue();
+
+ /**
+ * This method receives a value of type T, and checks whether it
corresponds to a "ghost" entry as implemented by a
+ * specific subclass. Please make sure to implement it in a consistent
manner with respect to
+ * {@link #createGhostValue() }.
+ *
+ * @param value
+ * the value to check.
+ * @return whether the value corresponds to a ghost entry.
+ */
+ protected abstract boolean isGhost(T value);
+
+ /**
+ * This method is called when the value backing the widget of type V has
changed so that the widget transitioned into
+ * or out of "ghost" state. It should implement the details of the
widget's appearance as it moves in or out of
+ * the ghost state.
+ *
+ * @param value
+ * the value backing the widget.
+ * @param widget
+ * the widget which is transitioning to/from ghost state.
+ * @param becomingGhost
+ * true if the item is entering ghost state, false if exiting
ghost state.
+ */
+ protected abstract void toggleGhost(T value, V widget, boolean
becomingGhost);
+
+}
--
To view, visit http://gerrit.ovirt.org/19530
To unsubscribe, visit http://gerrit.ovirt.org/settings
Gerrit-MessageType: newchange
Gerrit-Change-Id: I15958e4b7c1fcf0ec08ea35eb32c690964f2a366
Gerrit-PatchSet: 1
Gerrit-Project: ovirt-engine
Gerrit-Branch: master
Gerrit-Owner: Lior Vernia <lver...@redhat.com>
_______________________________________________
Engine-patches mailing list
Engine-patches@ovirt.org
http://lists.ovirt.org/mailman/listinfo/engine-patches
