AsyncPopupStep to prepare real PopupStep in background

platform/platform-impl/src/com/intellij/ui/popup/NextStepHandler.java

@@ -0,0 +1,8 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.popup;
+
+import com.intellij.openapi.ui.popup.PopupStep;
+
+public interface NextStepHandler {
+  void handleNextStep(final PopupStep nextStep, Object parentValue);
+}

platform/platform-impl/src/com/intellij/ui/popup/WizardPopup.java

@@ -25,6 +25,8 @@ import com.intellij.openapi.util.registry.Registry;
 import com.intellij.ui.PopupBorder;
 import com.intellij.ui.ScreenUtil;
 import com.intellij.ui.ScrollPaneFactory;
+import com.intellij.ui.popup.async.AsyncPopupImpl;
+import com.intellij.ui.popup.async.AsyncPopupStep;
 import com.intellij.ui.popup.list.ListPopupImpl;
 import com.intellij.ui.popup.tree.TreePopupImpl;
 import com.intellij.ui.popup.util.MnemonicsSearch;
@@ -394,6 +396,9 @@ public abstract class WizardPopup extends AbstractPopup implements ActionListene
   }
 
   protected WizardPopup createPopup(WizardPopup parent, PopupStep step, Object parentValue) {
+    if (step instanceof AsyncPopupStep) {
+      return new AsyncPopupImpl(parent, (AsyncPopupStep)step, parentValue);
+    }
     if (step instanceof ListPopupStep) {
       return new ListPopupImpl(parent, (ListPopupStep)step, parentValue);
     }

platform/platform-impl/src/com/intellij/ui/popup/async/AsyncPopupImpl.java

@@ -0,0 +1,111 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.popup.async;
+
+import com.intellij.openapi.Disposable;
+import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.ui.popup.PopupStep;
+import com.intellij.openapi.util.Disposer;
+import com.intellij.ui.components.JBLabel;
+import com.intellij.ui.popup.NextStepHandler;
+import com.intellij.ui.popup.WizardPopup;
+import com.intellij.util.Alarm;
+import com.intellij.util.ui.AsyncProcessIcon;
+import com.intellij.util.ui.UIUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import javax.swing.border.EmptyBorder;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.event.KeyEvent;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+
+public class AsyncPopupImpl extends WizardPopup implements Runnable {
+
+  private final Future<PopupStep> myFuture;
+  private final Object myParentValue;
+  private final NextStepHandler myCallBackParent;
+  private final Alarm myAlarm;
+  private JPanel myPanel;
+
+  public AsyncPopupImpl(@Nullable WizardPopup parent, @NotNull AsyncPopupStep step, Object parentValue) {
+    super(parent, step);
+
+    if (!(parent instanceof NextStepHandler)) throw new IllegalArgumentException("parent must be NextStepHandler");
+
+    myCallBackParent = (NextStepHandler)parent;
+    myParentValue = parentValue;
+
+    myFuture = ApplicationManager.getApplication().executeOnPooledThread(step);
+
+    myAlarm = new Alarm(this);
+    myAlarm.addRequest(this, 200);
+    Disposer.register(this, new Disposable() {
+      @Override
+      public void dispose() {
+        if (!myFuture.isCancelled() && !myFuture.isDone()) {
+          myFuture.cancel(false);
+        }
+      }
+    });
+  }
+
+  @Override
+  public void run() {
+    if (myFuture.isCancelled()) return;
+
+    if (myFuture.isDone()) {
+      goBack();
+      try {
+        myCallBackParent.handleNextStep(myFuture.get(), myParentValue);
+      }
+      catch (InterruptedException e) {
+        //ignore
+      }
+      catch (ExecutionException e) {
+        //ignore
+      }
+      return;
+    }
+    myAlarm.addRequest(this, 200);
+  }
+
+  @Override
+  protected JComponent createContent() {
+    if (myPanel != null) return myPanel;
+    myPanel = new JPanel(new BorderLayout());
+    myPanel.add(new AsyncProcessIcon("Async Popup Step"), BorderLayout.WEST);
+    myPanel.add(new JBLabel("Loading..."), BorderLayout.CENTER);
+    myPanel.setBorder(new EmptyBorder(UIUtil.getListCellPadding()));
+    myPanel.setBackground(UIUtil.getListSelectionBackground());
+    myPanel.registerKeyboardAction(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        goBack();
+      }
+    }, KeyStroke.getKeyStroke(KeyEvent.VK_LEFT, 0), JComponent.WHEN_FOCUSED);
+    return myPanel;
+  }
+
+  @Override
+  protected JComponent getPreferredFocusableComponent() {
+    return createContent();
+  }
+
+  @Override
+  protected InputMap getInputMap() {
+    return null;
+  }
+
+  @Override
+  protected ActionMap getActionMap() {
+    return null;
+  }
+
+  @Override
+  protected void onChildSelectedFor(Object value) {
+  }
+}

platform/platform-impl/src/com/intellij/ui/popup/async/AsyncPopupStep.java

@@ -0,0 +1,72 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.popup.async;
+
+import com.intellij.openapi.ui.popup.MnemonicNavigationFilter;
+import com.intellij.openapi.ui.popup.PopupStep;
+import com.intellij.openapi.ui.popup.SpeedSearchFilter;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.concurrent.Callable;
+
+/**
+ * Use this "mock" popup step when you need long processing (I/O, network activity etc.) to build real one.
+ * The real example is a list of processes on remote host you can connect to with debugger.
+ * This step would be started as 'callable' on pooled thread as soon as AsyncPopupImpl instance with "Loading..." text is being created
+ * When real popup step is obtained from the background task, mock item would be automatically replaced with it.
+ */
+public abstract class AsyncPopupStep implements PopupStep, Callable<PopupStep> {
+  @Nullable
+  @Override
+  public String getTitle() {
+    return null;
+  }
+
+  @Nullable
+  @Override
+  public PopupStep onChosen(Object selectedValue, boolean finalChoice) {
+    return null;
+  }
+
+  @Override
+  public boolean hasSubstep(Object selectedValue) {
+    return false;
+  }
+
+  @Override
+  public void canceled() {
+
+  }
+
+  @Override
+  public boolean isMnemonicsNavigationEnabled() {
+    return false;
+  }
+
+  @Nullable
+  @Override
+  public MnemonicNavigationFilter getMnemonicNavigationFilter() {
+    return null;
+  }
+
+  @Override
+  public boolean isSpeedSearchEnabled() {
+    return false;
+  }
+
+  @Nullable
+  @Override
+  public SpeedSearchFilter getSpeedSearchFilter() {
+    return null;
+  }
+
+  @Override
+  public boolean isAutoSelectionEnabled() {
+    return false;
+  }
+
+  @Nullable
+  @Override
+  public Runnable getFinalRunnable() {
+    return null;
+  }
+}

platform/platform-impl/src/com/intellij/ui/popup/list/ListPopupImpl.java

@@ -34,6 +34,7 @@ import com.intellij.ui.awt.RelativePoint;
 import com.intellij.ui.components.JBList;
 import com.intellij.ui.popup.ClosableByLeftArrow;
 import com.intellij.ui.popup.HintUpdateSupply;
+import com.intellij.ui.popup.NextStepHandler;
 import com.intellij.ui.popup.WizardPopup;
 import com.intellij.util.ui.UIUtil;
 import org.jetbrains.annotations.NotNull;
@@ -47,7 +48,7 @@ import java.awt.event.*;
 import java.util.Arrays;
 import java.util.concurrent.atomic.AtomicBoolean;
 
-public class ListPopupImpl extends WizardPopup implements ListPopup {
+public class ListPopupImpl extends WizardPopup implements ListPopup, NextStepHandler {
   private static final Logger LOG = Logger.getInstance("#com.intellij.ui.popup.list.ListPopupImpl");
 
   private MyList myList;
@@ -421,7 +422,11 @@ public class ListPopupImpl extends WizardPopup implements ListPopup {
     }
   }
 
-  private boolean handleNextStep(final PopupStep nextStep, Object parentValue, InputEvent e) {
+  public void handleNextStep(final PopupStep nextStep, Object parentValue) {
+    handleNextStep(nextStep, parentValue, null);
+  }
+
+  public boolean handleNextStep(final PopupStep nextStep, Object parentValue, InputEvent e) {
     if (nextStep != PopupStep.FINAL_CHOICE) {
       final Point point = myList.indexToLocation(myList.getSelectedIndex());
       SwingUtilities.convertPointToScreen(point, myList);

platform/platform-impl/src/com/intellij/ui/popup/tree/TreePopupImpl.java

@@ -27,6 +27,7 @@ import com.intellij.openapi.ui.popup.PopupStep;
 import com.intellij.openapi.ui.popup.TreePopup;
 import com.intellij.openapi.ui.popup.TreePopupStep;
 import com.intellij.ui.awt.RelativePoint;
+import com.intellij.ui.popup.NextStepHandler;
 import com.intellij.ui.popup.WizardPopup;
 import com.intellij.ui.treeStructure.SimpleTree;
 import com.intellij.ui.treeStructure.filtered.FilteringTreeBuilder;
@@ -46,7 +47,7 @@ import java.util.Enumeration;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
 
-public class TreePopupImpl extends WizardPopup implements TreePopup {
+public class TreePopupImpl extends WizardPopup implements TreePopup, NextStepHandler {
   private static final Logger LOG = Logger.getInstance("#com.intellij.ui.popup.tree.TreePopupImpl");
   private MyTree myWizardTree;
 
@@ -382,7 +383,7 @@ public class TreePopupImpl extends WizardPopup implements TreePopup {
     }
   }
 
-  private void handleNextStep(PopupStep nextStep, Object parentValue) {
+  public void handleNextStep(PopupStep nextStep, Object parentValue) {
     final Rectangle pathBounds = myWizardTree.getPathBounds(myWizardTree.getSelectionPath());
     final Point point = new RelativePoint(myWizardTree, new Point(getContent().getWidth() + 2, (int) pathBounds.getY())).getScreenPoint();
     myChild = createPopup(this, nextStep, parentValue);