DragAndDropFiles.java

package com.vaadin.tests.dd;

import java.io.OutputStream;

import org.apache.commons.io.output.NullOutputStream;

import com.vaadin.event.dd.DragAndDropEvent;
import com.vaadin.event.dd.DropHandler;
import com.vaadin.event.dd.acceptcriteria.AcceptAll;
import com.vaadin.event.dd.acceptcriteria.AcceptCriterion;
import com.vaadin.server.StreamVariable;
import com.vaadin.tests.components.TestBase;
import com.vaadin.ui.Component;
import com.vaadin.ui.CssLayout;
import com.vaadin.ui.DragAndDropWrapper;
import com.vaadin.ui.DragAndDropWrapper.WrapperTransferable;
import com.vaadin.ui.Html5File;
import com.vaadin.ui.Label;

public class DragAndDropFiles extends TestBase {

    @Override
    protected void setup() {
        CssLayout cssLayout = new CssLayout() {
            @Override
            protected String getCss(Component c) {
                return "display: block; padding:20px; border: 2px dotted black; background: #aaa;";
            }
        };
        Component l = new Label("Drag file on me");
        l.setSizeUndefined();
        cssLayout.addComponent(l);
        DragAndDropWrapper dragAndDropWrapper = new DragAndDropWrapper(
                cssLayout);
        dragAndDropWrapper.setSizeUndefined();
        dragAndDropWrapper.setDropHandler(new DropHandler() {

            @Override
            public AcceptCriterion getAcceptCriterion() {
                return AcceptAll.get();
            }

            @Override
            public void drop(DragAndDropEvent event) {
                WrapperTransferable transferable = (WrapperTransferable) event
                        .getTransferable();
                Html5File[] files = transferable.getFiles();
                if (files != null) {

                    for (int i = 0; i < files.length; i++) {
                        Html5File file = files[i];
                        // Max 1 MB files are uploaded
                        if (file.getFileSize() > 1024 * 1024) {
                            getMainWindow().showNotification("File "
                                    + file.getFileName()
                                    + " was too large, not transferred to the server side.");
                            continue;
                        }

                        StreamVariable streamVariable = new StreamVariable() {

                            @Override
                            public OutputStream getOutputStream() {
                                return new NullOutputStream();
                            }

                            @Override
                            public boolean listenProgress() {
                                return true;
                            }

                            @Override
                            public void onProgress(
                                    StreamingProgressEvent event) {
                                System.err.println(
                                        "Progress" + event.getBytesReceived());
                            }

                            @Override
                            public void streamingStarted(
                                    StreamingStartEvent event) {
                                getMainWindow()
                                        .showNotification("Started uploading "
                                                + event.getFileName());
                            }

                            @Override
                            public void streamingFinished(
                                    StreamingEndEvent event) {
                                getMainWindow()
                                        .showNotification("Finished uploading "
                                                + event.getFileName());
                            }

                            @Override
                            public void streamingFailed(
                                    StreamingErrorEvent event) {
                                getMainWindow()
                                        .showNotification("Failed uploading "
                                                + event.getFileName());
                            }

                            @Override
                            public boolean isInterrupted() {
                                return false;
                            }
                        };
                        file.setStreamVariable(streamVariable);
                    }
                }

            }
        });

        addComponent(dragAndDropWrapper);
    }

    /*
     * TODO implement 'handbrake' for testing, progresss listener, interrupting.
     */
    @Override
    protected String getDescription() {
        return "Should work. Over 1 MB files will not be posted. TODO implement 'handbrake' for testing, progresss listener, interrupting.";
    }

    @Override
    protected Integer getTicketNumber() {
        return null;
    }

}