SplitEditorToolbar.java

package org.intellij.plugins.markdown.ui.split;

import com.intellij.openapi.Disposable;
import com.intellij.openapi.actionSystem.ActionGroup;
import com.intellij.openapi.actionSystem.ActionManager;
import com.intellij.openapi.actionSystem.ActionPlaces;
import com.intellij.openapi.actionSystem.ActionToolbar;
import com.intellij.openapi.actionSystem.impl.ActionToolbarImpl;
import com.intellij.openapi.editor.ex.EditorGutterComponentEx;
import com.intellij.util.ui.JBEmptyBorder;
import com.intellij.util.ui.JBUI;
import com.intellij.util.ui.UIUtil;
import org.intellij.plugins.markdown.MarkdownBundle;
import org.jetbrains.annotations.NotNull;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.util.ArrayList;
import java.util.List;

public class SplitEditorToolbar extends JPanel implements Disposable {
  private static final String LEFT_TOOLBAR_GROUP_ID = "Markdown.Toolbar.Left";
  private static final String RIGHT_TOOLBAR_GROUP_ID = "Markdown.Toolbar.Right";

  private final MySpacingPanel mySpacingPanel;

  private final ActionToolbar myRightToolbar;

  private final List<EditorGutterComponentEx> myGutters = new ArrayList<>();

  private final ComponentAdapter myAdjustToGutterListener = new ComponentAdapter() {
    @Override
    public void componentResized(ComponentEvent e) {
      adjustSpacing();
    }

    @Override
    public void componentShown(ComponentEvent e) {
      adjustSpacing();
    }

    @Override
    public void componentHidden(ComponentEvent e) {
      adjustSpacing();
    }
  };

  public SplitEditorToolbar(@NotNull final JComponent targetComponentForActions) {
    super(new GridBagLayout());

    final ActionToolbar leftToolbar = createToolbarFromGroupId(LEFT_TOOLBAR_GROUP_ID);
    leftToolbar.setTargetComponent(targetComponentForActions);
    myRightToolbar = createToolbarFromGroupId(RIGHT_TOOLBAR_GROUP_ID);
    myRightToolbar.setTargetComponent(targetComponentForActions);

    mySpacingPanel = new MySpacingPanel((int)leftToolbar.getComponent().getPreferredSize().getHeight());
    final JPanel centerPanel = new JPanel(new BorderLayout());
    centerPanel.add(new JLabel(MarkdownBundle.message("markdown.toolbar.view.label"), SwingConstants.RIGHT), BorderLayout.EAST);

    add(mySpacingPanel);
    add(leftToolbar.getComponent());
    add(centerPanel,
        new GridBagConstraints(2, 0, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, JBUI.emptyInsets(), 0, 0));
    add(myRightToolbar.getComponent());

    setBorder(BorderFactory.createMatteBorder(0, 0, 1, 0, UIUtil.CONTRAST_BORDER_COLOR));

    addComponentListener(myAdjustToGutterListener);
  }

  public void addGutterToTrack(@NotNull EditorGutterComponentEx gutterComponentEx) {
    myGutters.add(gutterComponentEx);

    gutterComponentEx.addComponentListener(myAdjustToGutterListener);
  }

  public void refresh() {
    adjustSpacing();
    myRightToolbar.updateActionsImmediately();
  }

  private void adjustSpacing() {
    EditorGutterComponentEx leftMostGutter = null;
    for (EditorGutterComponentEx gutter : myGutters) {
      if (!gutter.isShowing()) {
        continue;
      }
      if (leftMostGutter == null || leftMostGutter.getX() > gutter.getX()) {
        leftMostGutter = gutter;
      }
    }

    final int spacing;
    if (leftMostGutter == null) {
      spacing = 0;
    }
    else {
      spacing = leftMostGutter.getWhitespaceSeparatorOffset();
    }
    mySpacingPanel.setSpacing(spacing);

    revalidate();
    repaint();
  }

  @Override
  public void dispose() {
    removeComponentListener(myAdjustToGutterListener);
    for (EditorGutterComponentEx gutter : myGutters) {
      gutter.removeComponentListener(myAdjustToGutterListener);
    }
  }

  @NotNull
  private static ActionToolbar createToolbarFromGroupId(@NotNull String groupId) {
    final ActionManager actionManager = ActionManager.getInstance();

    if (!actionManager.isGroup(groupId)) {
      throw new IllegalStateException(groupId + " should have been a group");
    }
    final ActionGroup group = ((ActionGroup)actionManager.getAction(groupId));
    final ActionToolbarImpl editorToolbar =
      ((ActionToolbarImpl)actionManager.createActionToolbar(ActionPlaces.EDITOR_TOOLBAR, group, true));
    editorToolbar.setOpaque(false);
    editorToolbar.setBorder(new JBEmptyBorder(0, 2, 0, 2));

    return editorToolbar;
  }

  private static class MySpacingPanel extends JPanel {
    private final int myHeight;

    private int mySpacing;

    public MySpacingPanel(int height) {
      myHeight = height;
      mySpacing = 0;
      setOpaque(false);
    }

    @Override
    public Dimension getPreferredSize() {
      return new Dimension(mySpacing, myHeight);
    }

    public void setSpacing(int spacing) {
      mySpacing = spacing;
    }
  }
}