ResizeHandleView.java

package jetbrains.mps.lang.editor.diagram.runtime.jetpad.views;

/*Generated by MPS */

import jetbrains.jetpad.projectional.view.PolyLineView;
import jetbrains.jetpad.model.property.Property;
import jetbrains.jetpad.values.Color;
import jetbrains.jetpad.model.property.ValueProperty;
import jetbrains.jetpad.geometry.Vector;
import jetbrains.jetpad.mapper.Mapper;
import jetbrains.jetpad.mapper.Synchronizers;
import jetbrains.jetpad.model.property.WritableProperty;
import jetbrains.jetpad.base.Registration;
import jetbrains.jetpad.projectional.view.ViewTrait;
import jetbrains.jetpad.projectional.view.ViewTraitBuilder;
import jetbrains.jetpad.projectional.view.ViewEvents;
import jetbrains.jetpad.projectional.view.ViewEventHandler;
import jetbrains.jetpad.event.MouseEvent;
import jetbrains.jetpad.projectional.view.View;

public class ResizeHandleView extends PolyLineView {
  public static final int DEFAULT_HALF_WIDTH = 3;

  public Property<Color> color = new ValueProperty<Color>(Color.GRAY);
  public Property<Color> backgroundColor = new ValueProperty<Color>(Color.LIGHT_GRAY);
  public Property<Integer> halfWidth = new ValueProperty<Integer>(DEFAULT_HALF_WIDTH);
  public Property<Vector> centerLocation = new ValueProperty<Vector>(new Vector(0, 0));
  public Property<DragHandler> dragHandler = new ValueProperty<DragHandler>();

  private ResizeHandleView() {
    new Mapper<ResizeHandleView, ResizeHandleView>(this, this) {
      @Override
      protected void registerSynchronizers(Mapper.SynchronizersConfiguration configuration) {
        super.registerSynchronizers(configuration);
        configuration.add(Synchronizers.forProperty(color, color()));
        configuration.add(Synchronizers.forProperty(backgroundColor, background()));
        configuration.add(Synchronizers.forProperty(halfWidth, new Runnable() {
          public void run() {
            updateLocation(centerLocation.get(), halfWidth.get());
          }
        }));
        configuration.add(Synchronizers.forProperty(centerLocation, new Runnable() {
          public void run() {
            updateLocation(centerLocation.get(), halfWidth.get());
          }
        }));
        configuration.add(Synchronizers.forProperty(dragHandler, new WritableProperty<DragHandler>() {
          private Registration myRegistration;
          public void set(DragHandler handler) {
            if (myRegistration != null) {
              myRegistration.remove();
            }
            if (handler != null) {
              myRegistration = addTrait(getResizeHandlingTrait());
            }
          }
        }));
      }
    }.attachRoot();
  }
  public ResizeHandleView(Vector location) {
    this();
    centerLocation.set(location);
  }
  @Override
  protected boolean contains(Vector vector) {
    return dragHandler.get() != null;
  }
  private ViewTrait getResizeHandlingTrait() {
    return new ViewTraitBuilder().on(ViewEvents.MOUSE_PRESSED, new ViewEventHandler<MouseEvent>() {
      public void handle(View view, MouseEvent event) {
        dragHandler.get().dragStarted(event.location());
        event.consume();
      }
    }).on(ViewEvents.MOUSE_DRAGGED, new ViewEventHandler<MouseEvent>() {
      public void handle(View view, MouseEvent event) {
        dragHandler.get().updatePosition(event.location());
      }
    }).on(ViewEvents.MOUSE_RELEASED, new ViewEventHandler<MouseEvent>() {
      public void handle(View view, MouseEvent event) {
        dragHandler.get().dragStopped(event.location());
      }
    }).build();
  }
  private void updateLocation(Vector location, int halfWidth) {
    points.clear();
    points.add(new Vector(location.x - halfWidth, location.y - halfWidth));
    points.add(new Vector(location.x + halfWidth, location.y - halfWidth));
    points.add(new Vector(location.x + halfWidth, location.y + halfWidth));
    points.add(new Vector(location.x - halfWidth, location.y + halfWidth));
    points.add(new Vector(location.x - halfWidth, location.y - halfWidth));
  }
}