Difference between revisions of "Menu Contributions/Radio Button Command"

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Line 5: Line 5:
 
You want to create a command that will be executed with a paramter.  The parameter in this example matches which of the radio buttons is selected.
 
You want to create a command that will be executed with a paramter.  The parameter in this example matches which of the radio buttons is selected.
  
<command
+
<source lang="xml">
      categoryId="org.eclipse.ui.category.help"
+
<command
      defaultHandler="z.ex.dropdown.internal.RadioHandler"
+
        categoryId="org.eclipse.ui.category.help"
      id="z.ex.dropdown.radio"
+
        defaultHandler="z.ex.dropdown.internal.RadioHandler"
      name="Radio Example">
+
        id="z.ex.dropdown.radio"
 +
        name="Radio Example">
 
     <commandParameter
 
     <commandParameter
          id="z.ex.dropdown.radio.info"
+
            id="z.ex.dropdown.radio.info"
          name="Radio Name"
+
            name="Radio Name"
          optional="false">
+
            optional="false">
 
     </commandParameter>
 
     </commandParameter>
</command>
+
</command>
 
+
</source>
  
 
== Handler ==
 
== Handler ==
Line 22: Line 23:
 
The handler will receive the parameter.  It can then update its model (in my example my '''model''' is a local variable, but that might not be appropriate in command that can have multiple handlers).
 
The handler will receive the parameter.  It can then update its model (in my example my '''model''' is a local variable, but that might not be appropriate in command that can have multiple handlers).
  
package com.example.handlers.internal;
+
<source lang="java">
+
package com.example.handlers.internal;
import java.util.Map;
+
 
import org.eclipse.core.commands.AbstractHandler;
+
import java.util.Map;
import org.eclipse.core.commands.ExecutionEvent;
+
import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionException;
+
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.ui.commands.ICommandService;
+
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.ui.commands.IElementUpdater;
+
import org.eclipse.ui.commands.ICommandService;
import org.eclipse.ui.handlers.HandlerUtil;
+
import org.eclipse.ui.commands.IElementUpdater;
import org.eclipse.ui.menus.UIElement;
+
import org.eclipse.ui.handlers.HandlerUtil;
+
import org.eclipse.ui.menus.UIElement;
public class RadioHandler extends AbstractHandler implements IElementUpdater {
+
 
   
+
public class RadioHandler extends AbstractHandler implements IElementUpdater {
  private static final String PARM_INFO = "z.ex.dropdown.radio.info";
+
 
  private String fCurrentValue;
+
  private static final String PARM_INFO = "z.ex.dropdown.radio.info";
+
private String fCurrentValue;
  public Object execute(ExecutionEvent event) throws ExecutionException {
+
 
    String parm = event.getParameter(PARM_INFO);
+
public Object execute(ExecutionEvent event) throws ExecutionException {
    if (parm.equals(fCurrentValue)) {
+
  String parm = event.getParameter(PARM_INFO);
      return null; // in theory, we're already in the correct state
+
  if (parm.equals(fCurrentValue)) {
    }
+
    return null; // in theory, we're already in the correct state
   
+
  }
    // do whatever having "parm" active implies
+
 
    fCurrentValue = parm;
+
  // do whatever having "parm" active implies
   
+
  fCurrentValue = parm;
   
+
 
    // update our radio button states ... get the service from
+
 
    // a place that's most appropriate
+
  // update our radio button states ... get the service from
    ICommandService service = (ICommandService) HandlerUtil
+
  // a place that's most appropriate
        .getActiveWorkbenchWindowChecked(event).getService(
+
  ICommandService service = (ICommandService) HandlerUtil
            ICommandService.class);
+
      .getActiveWorkbenchWindowChecked(event).getService(
    service.refreshElements(event.getCommand().getId(), null);
+
          ICommandService.class);
    return null;
+
  service.refreshElements(event.getCommand().getId(), null);
  }
+
  return null;
+
  public void updateElement(UIElement element, Map parameters) {
+
    String parm = (String) parameters.get(PARM_INFO);
+
    if (parm != null) {
+
      if (fCurrentValue != null && fCurrentValue.equals(parm)) {
+
        element.setChecked(true);
+
      } else {
+
        element.setChecked(false);
+
      }
+
    }
+
  }
+
 
  }
 
  }
 +
 +
public void updateElement(UIElement element, Map parameters) {
 +
  String parm = (String) parameters.get(PARM_INFO);
 +
  if (parm != null) {
 +
    if (fCurrentValue != null && fCurrentValue.equals(parm)) {
 +
      element.setChecked(true);
 +
    } else {
 +
      element.setChecked(false);
 +
    }
 +
  }
 +
}
 +
}
 +
</source>
  
 
== Menu Contribution ==
 
== Menu Contribution ==
Line 73: Line 76:
 
Then you add menu contributions with the specific parameters that you want:
 
Then you add menu contributions with the specific parameters that you want:
  
      <menuContribution
+
<source lang="xml">
            locationURI="menu:help?after=additions">
+
<menuContribution
        <separator
+
        locationURI="menu:help?after=additions">
              name="z.ex.dropdown.menu.separator1"
+
    <separator
              visible="true">
+
            name="z.ex.dropdown.menu.separator1"
        </separator>
+
            visible="true">
        <command
+
    </separator>
              commandId="z.ex.dropdown.radio"
+
    <command
              id="z.ex.dropdown.menu.radio1"
+
            commandId="z.ex.dropdown.radio"
              label="Moe"
+
            id="z.ex.dropdown.menu.radio1"
              style="radio">
+
            label="Moe"
            <parameter
+
            style="radio">
                  name="z.ex.dropdown.radio.info"
+
        <parameter
                  value="Moe">
+
                name="z.ex.dropdown.radio.info"
            </parameter>
+
                value="Moe">
        </command>
+
        </parameter>
        <command
+
    </command>
              commandId="z.ex.dropdown.radio"
+
    <command
              id="z.ex.dropdown.menu.radio2"
+
            commandId="z.ex.dropdown.radio"
              label="Larry"
+
            id="z.ex.dropdown.menu.radio2"
              style="radio">
+
            label="Larry"
            <parameter
+
            style="radio">
                  name="z.ex.dropdown.radio.info"
+
        <parameter
                  value="Larry">
+
            name="z.ex.dropdown.radio.info"
            </parameter>
+
            value="Larry">
        </command>
+
        </parameter>
        <command
+
    </command>
              commandId="z.ex.dropdown.radio"
+
    <command
              id="z.ex.dropdown.menu.radio3"
+
            commandId="z.ex.dropdown.radio"
              label="Curly"
+
            id="z.ex.dropdown.menu.radio3"
              style="radio">
+
            label="Curly"
            <parameter
+
            style="radio">
                  name="z.ex.dropdown.radio.info"
+
        <parameter
                  value="Curly">
+
                name="z.ex.dropdown.radio.info"
            </parameter>
+
                value="Curly">
        </command>
+
        </parameter>
        <separator
+
    </command>
              name="z.ex.dropdown.menu.separator2"
+
    <separator
              visible="true">
+
            name="z.ex.dropdown.menu.separator2"
        </separator>
+
            visible="true">
      </menuContribution>
+
    </separator>
  </extension>
+
</menuContribution>
 +
</source>
  
 
== Initializing the Handler ==
 
== Initializing the Handler ==
Line 120: Line 124:
 
It may happen that your radio menu contributions are not initialized the first time the menu is displayed. This is because at this time, your Handler might not yet have been instantiated (this is due to Eclipse's lazy loading policy). If this is the case, you can enforce the instantiation of your Handler within the Activator of your plug-in. Just add the following code to the start(BundleContext) method:
 
It may happen that your radio menu contributions are not initialized the first time the menu is displayed. This is because at this time, your Handler might not yet have been instantiated (this is due to Eclipse's lazy loading policy). If this is the case, you can enforce the instantiation of your Handler within the Activator of your plug-in. Just add the following code to the start(BundleContext) method:
  
UIJob job = new UIJob("InitCommandsWorkaround") {
+
<source lang="java">
+
UIJob job = new UIJob("InitCommandsWorkaround") {
    @Override
+
 
    public IStatus runInUIThread(@SuppressWarnings("unused") IProgressMonitor monitor) {
+
    public IStatus runInUIThread(@SuppressWarnings("unused") IProgressMonitor monitor) {
   
+
   
        ICommandService commandService = (ICommandService) PlatformUI
+
        ICommandService commandService = (ICommandService) PlatformUI
            .getWorkbench().getActiveWorkbenchWindow().getService(
+
            .getWorkbench().getActiveWorkbenchWindow().getService(
                ICommandService.class);
+
                ICommandService.class);
        Command command = commandService.getCommand("z.ex.dropdown.radio");
+
        Command command = commandService.getCommand("z.ex.dropdown.radio");
        command.isEnabled();
+
        command.isEnabled();
        return new Status(IStatus.OK,
+
        return new Status(IStatus.OK,
            "my.plugin.id",
+
            "my.plugin.id",
            "Init commands workaround performed succesfully");
+
            "Init commands workaround performed succesfully");
    }
+
    }
+
 
};
+
};
job.schedule();
+
job.schedule();
 +
</source>

Revision as of 15:25, 9 March 2008

You can create a command with a required parameter. The parameter will be passed during every execution.

Contents

Command Definition

You want to create a command that will be executed with a paramter. The parameter in this example matches which of the radio buttons is selected.

<command
        categoryId="org.eclipse.ui.category.help"
        defaultHandler="z.ex.dropdown.internal.RadioHandler"
        id="z.ex.dropdown.radio"
        name="Radio Example">
    <commandParameter
            id="z.ex.dropdown.radio.info"
            name="Radio Name"
            optional="false">
    </commandParameter>
</command>

Handler

The handler will receive the parameter. It can then update its model (in my example my model is a local variable, but that might not be appropriate in command that can have multiple handlers).

package com.example.handlers.internal;
 
import java.util.Map;
import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.ui.commands.ICommandService;
import org.eclipse.ui.commands.IElementUpdater;
import org.eclipse.ui.handlers.HandlerUtil;
import org.eclipse.ui.menus.UIElement;
 
public class RadioHandler extends AbstractHandler implements IElementUpdater {
 
 private static final String PARM_INFO = "z.ex.dropdown.radio.info";
 private String fCurrentValue;
 
 public Object execute(ExecutionEvent event) throws ExecutionException {
   String parm = event.getParameter(PARM_INFO);
   if (parm.equals(fCurrentValue)) {
     return null; // in theory, we're already in the correct state
   }
 
   // do whatever having "parm" active implies
   fCurrentValue = parm;
 
 
   // update our radio button states ... get the service from
   // a place that's most appropriate
   ICommandService service = (ICommandService) HandlerUtil
       .getActiveWorkbenchWindowChecked(event).getService(
           ICommandService.class);
   service.refreshElements(event.getCommand().getId(), null);
   return null;
 }
 
 public void updateElement(UIElement element, Map parameters) {
   String parm = (String) parameters.get(PARM_INFO);
   if (parm != null) {
     if (fCurrentValue != null && fCurrentValue.equals(parm)) {
       element.setChecked(true);
     } else {
       element.setChecked(false);
     }
   }
 }
}

Menu Contribution

Then you add menu contributions with the specific parameters that you want:

<menuContribution
        locationURI="menu:help?after=additions">
    <separator
            name="z.ex.dropdown.menu.separator1"
            visible="true">
    </separator>
    <command
            commandId="z.ex.dropdown.radio"
            id="z.ex.dropdown.menu.radio1"
            label="Moe"
            style="radio">
        <parameter
                name="z.ex.dropdown.radio.info"
                value="Moe">
        </parameter>
    </command>
    <command
            commandId="z.ex.dropdown.radio"
            id="z.ex.dropdown.menu.radio2"
            label="Larry"
            style="radio">
        <parameter
            name="z.ex.dropdown.radio.info"
            value="Larry">
        </parameter>
    </command>
    <command
            commandId="z.ex.dropdown.radio"
            id="z.ex.dropdown.menu.radio3"
            label="Curly"
            style="radio">
        <parameter
                name="z.ex.dropdown.radio.info"
                value="Curly">
        </parameter>
    </command>
    <separator
            name="z.ex.dropdown.menu.separator2"
            visible="true">
    </separator>
</menuContribution>

Initializing the Handler

It may happen that your radio menu contributions are not initialized the first time the menu is displayed. This is because at this time, your Handler might not yet have been instantiated (this is due to Eclipse's lazy loading policy). If this is the case, you can enforce the instantiation of your Handler within the Activator of your plug-in. Just add the following code to the start(BundleContext) method:

UIJob job = new UIJob("InitCommandsWorkaround") {
 
    public IStatus runInUIThread(@SuppressWarnings("unused") IProgressMonitor monitor) {
 
        ICommandService commandService = (ICommandService) PlatformUI
            .getWorkbench().getActiveWorkbenchWindow().getService(
                ICommandService.class);
        Command command = commandService.getCommand("z.ex.dropdown.radio");
        command.isEnabled();
        return new Status(IStatus.OK,
            "my.plugin.id",
            "Init commands workaround performed succesfully");
    }
 
};
job.schedule();