how to post progress messages to a window for long running processs?

answered 2013-03-27 08:19:12 +0800

benbai
2228 ● 6
http://www.zkoss.org

You need to do those steps in another thread, also pass vm to that thread so you can update properties of vm as needed, and use timer to update properties.

For more information, please refer to the simple sample below:

test.zul

<zk>
    <div apply="org.zkoss.bind.BindComposer"
        viewModel="@id('vm') @init('test.TestVM')">
        <button id="btn" label="do multiple steps long operation"
            onClick="@command('doLongSteps')" />
        <label value="@load(vm.msg)" />
        <timer running="@load(vm.isRunning)" repeats="true"
            delay="500" onTimer="@command('checkStatus')" />    
    </div>
</zk>

TestVM.java

package test;

import org.zkoss.bind.annotation.Command;
import org.zkoss.bind.annotation.NotifyChange;
import org.zkoss.zk.ui.util.Clients;

public class TestVM {
    String _msg;
    boolean _isRunning;

    public void setMsg (String msg) {
        _msg = msg;
    }
    public String getMsg () {
        return _msg;
    }
    public void setIsRunning (boolean isRunning) {
        _isRunning = isRunning;
    }
    public boolean getIsRunning () {
        return _isRunning;
    }
    @Command
    @NotifyChange({"isRunning", "msg"})
    public void doLongSteps () {
        _isRunning = true;
        new Thread(new MultiStepsLongOperationWorker(this)).start();
    }
    @Command
    @NotifyChange({"isRunning", "msg"})
    public void checkStatus () {
        if (_isRunning) {
            Clients.showBusy(_msg);
        } else {
            Clients.clearBusy();
        }
    }
}

MultiStepsLongOperationWorker.java

package test;

import java.util.Random;

public class MultiStepsLongOperationWorker implements Runnable {

    private TestVM _vm;
    public MultiStepsLongOperationWorker (TestVM vm) {
        _vm = vm;
    }
    public void run () {
        int step = 1;
        Random r = new Random();
        while (step <= 9) {
            _vm.setMsg("Processing step " + step + "...");
            try {
                Thread.sleep(r.nextInt(2000) + 1000);
            } catch (Exception e) {
                e.printStackTrace();
            }
            step++;
        }
        _vm.setIsRunning(false);
    }
}

answered 2013-03-26 04:57:57 +0800

ashishd
1972 ● 6

For now you can refer to this tracker ZK-1141 comments section where Dennis has put links to 4 gist samples to demo how to implement long running operations with ZK MVVM