/*
* Copyright 2000-2016 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.intellij.openapi.editor.ex.util;
import com.intellij.openapi.editor.Document;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.editor.EditorFactory;
import com.intellij.openapi.editor.ScrollingModel;
import org.jetbrains.annotations.Nullable;
import java.awt.*;
import java.util.HashMap;
import java.util.Map;
/**
* Allows to keep caret's position in editor window at the same vertical position for operations, that can potentially move caret.
* An instance of this class is to be created before the operation, method {@link #restoreOriginalLocation()} should be called after it.
*/
public class CaretVisualPositionKeeper {
private final Map<Editor, Integer> myCaretRelativeVerticalPositions = new HashMap<>();
public CaretVisualPositionKeeper(@Nullable Editor editor) {
this(editor == null ? Editor.EMPTY_ARRAY : new Editor[]{editor});
}
public CaretVisualPositionKeeper(@Nullable Document document) {
this(document == null ? Editor.EMPTY_ARRAY : EditorFactory.getInstance().getEditors(document));
}
private CaretVisualPositionKeeper(Editor[] editors) {
for (Editor editor : editors) {
Rectangle visibleArea = editor.getScrollingModel().getVisibleAreaOnScrollingFinished();
Point pos = editor.visualPositionToXY(editor.getCaretModel().getVisualPosition());
int relativePosition = pos.y - visibleArea.y;
myCaretRelativeVerticalPositions.put(editor, relativePosition);
}
}
public void restoreOriginalLocation() {
for (Map.Entry<Editor, Integer> e : myCaretRelativeVerticalPositions.entrySet()) {
Editor editor = e.getKey();
int relativePosition = e.getValue();
Point caretLocation = editor.visualPositionToXY(editor.getCaretModel().getVisualPosition());
int scrollOffset = caretLocation.y - relativePosition;
ScrollingModel scrollingModel = editor.getScrollingModel();
Rectangle targetArea = scrollingModel.getVisibleAreaOnScrollingFinished();
// when animated scrolling is in progress, we'll not stop it immediately
boolean useAnimation = !targetArea.equals(scrollingModel.getVisibleArea());
if (!useAnimation) scrollingModel.disableAnimation();
scrollingModel.scroll(targetArea.x, scrollOffset);
if (!useAnimation) scrollingModel.enableAnimation();
}
}
}