| // Copyright 2004 The Apache Software Foundation |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package org.apache.tapestry.form; |
| |
| import java.io.IOException; |
| import java.util.Iterator; |
| |
| import org.apache.tapestry.ApplicationRuntimeException; |
| import org.apache.tapestry.IActionListener; |
| import org.apache.tapestry.IBinding; |
| import org.apache.tapestry.IForm; |
| import org.apache.tapestry.IMarkupWriter; |
| import org.apache.tapestry.IRequestCycle; |
| import org.apache.tapestry.Tapestry; |
| import org.apache.tapestry.request.RequestContext; |
| import org.apache.tapestry.util.io.DataSqueezer; |
| |
| /** |
| * A specialized component used to edit a list of items |
| * within a form; it is similar to a {@link org.apache.tapestry.components.Foreach} but leverages |
| * hidden inputs within the <form> to store the items in the list. |
| * |
| * [<a href="../../../../../ComponentReference/ListEdit.html">Component Reference</a>] |
| * |
| * @author Howard Lewis Ship |
| * @version $Id$ |
| * @since 1.0.2 |
| * |
| **/ |
| |
| public abstract class ListEdit extends AbstractFormComponent |
| { |
| |
| protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle) |
| { |
| Iterator i = null; |
| |
| IForm form = getForm(cycle); |
| |
| boolean cycleRewinding = cycle.isRewinding(); |
| |
| // If the cycle is rewinding, but not this particular form, |
| // then do nothing (don't even render the body). |
| |
| if (cycleRewinding && !form.isRewinding()) |
| return; |
| |
| String name = form.getElementId(this); |
| |
| if (!cycleRewinding) |
| { |
| i = Tapestry.coerceToIterator(getSourceBinding().getObject()); |
| } |
| else |
| { |
| RequestContext context = cycle.getRequestContext(); |
| String[] submittedValues = context.getParameters(name); |
| |
| i = Tapestry.coerceToIterator(submittedValues); |
| } |
| |
| // If the source (when rendering), or the submitted values (on submit) |
| // are null, then skip the remainder (nothing to update, nothing to |
| // render). |
| |
| if (i == null) |
| return; |
| |
| int index = 0; |
| |
| IBinding indexBinding = getIndexBinding(); |
| IBinding valueBinding = getValueBinding(); |
| IActionListener listener = getListener(); |
| String element = getElement(); |
| |
| while (i.hasNext()) |
| { |
| Object value = null; |
| |
| if (indexBinding != null) |
| indexBinding.setInt(index++); |
| |
| if (cycleRewinding) |
| value = convertValue((String) i.next()); |
| else |
| { |
| value = i.next(); |
| writeValue(form, name, value); |
| } |
| |
| valueBinding.setObject(value); |
| |
| if (listener != null) |
| listener.actionTriggered(this, cycle); |
| |
| if (element != null) |
| { |
| writer.begin(element); |
| renderInformalParameters(writer, cycle); |
| } |
| |
| renderBody(writer, cycle); |
| |
| if (element != null) |
| writer.end(); |
| |
| } |
| } |
| |
| private void writeValue(IForm form, String name, Object value) |
| { |
| String externalValue; |
| |
| try |
| { |
| externalValue = getDataSqueezer().squeeze(value); |
| } |
| catch (IOException ex) |
| { |
| throw new ApplicationRuntimeException( |
| Tapestry.format("ListEdit.unable-to-convert-value", value), |
| this, |
| null, |
| ex); |
| } |
| |
| form.addHiddenValue(name, externalValue); |
| } |
| |
| private Object convertValue(String value) |
| { |
| try |
| { |
| return getDataSqueezer().unsqueeze(value); |
| } |
| catch (IOException ex) |
| { |
| throw new ApplicationRuntimeException( |
| Tapestry.format("ListEdit.unable-to-convert-string", value), |
| this, |
| null, |
| ex); |
| } |
| } |
| |
| public abstract String getElement(); |
| |
| private DataSqueezer getDataSqueezer() |
| { |
| return getPage().getEngine().getDataSqueezer(); |
| } |
| |
| /** @since 2.2 **/ |
| |
| public abstract IActionListener getListener(); |
| |
| /** @since 3.0 **/ |
| |
| public abstract IBinding getSourceBinding(); |
| |
| public abstract IBinding getValueBinding(); |
| |
| public abstract IBinding getIndexBinding(); |
| |
| /** @since 3.0 **/ |
| |
| public boolean isDisabled() |
| { |
| return false; |
| } |
| |
| } |