Java tutorial
//Copyright (C) 2013 The Android Open Source Project // // 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.google.gerrit.client.diff; import com.google.gwt.core.client.GWT; import com.google.gwt.dom.client.Element; import com.google.gwt.dom.client.Style.Unit; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.event.dom.client.ClickHandler; import com.google.gwt.event.dom.client.MouseDownEvent; import com.google.gwt.event.dom.client.MouseMoveEvent; import com.google.gwt.event.dom.client.MouseUpEvent; import com.google.gwt.resources.client.CssResource; import com.google.gwt.uibinder.client.UiBinder; import com.google.gwt.uibinder.client.UiField; import com.google.gwt.uibinder.client.UiHandler; import com.google.gwt.user.client.DOM; import com.google.gwt.user.client.ui.Composite; import com.google.gwt.user.client.ui.HTMLPanel; import com.google.gwt.user.client.ui.Label; import com.google.gwt.user.client.ui.Widget; import net.codemirror.lib.CodeMirror; import net.codemirror.lib.LineCharacter; import net.codemirror.lib.ScrollInfo; import java.util.ArrayList; import java.util.HashSet; import java.util.List; import java.util.Set; /** Displays overview of all edits and comments in this file. */ class OverviewBar extends Composite implements ClickHandler { interface Binder extends UiBinder<HTMLPanel, OverviewBar> { } private static final Binder uiBinder = GWT.create(Binder.class); interface Style extends CssResource { String gutter(); String halfGutter(); String comment(); String draft(); String insert(); String delete(); String viewportDrag(); } enum MarkType { COMMENT, DRAFT, INSERT, DELETE, EDIT } @UiField Style style; @UiField Label viewport; private final List<MarkHandle> diff; private final Set<MarkHandle> comments; private CodeMirror cmB; private boolean dragging; private int startY; private double ratio; OverviewBar() { initWidget(uiBinder.createAndBindUi(this)); diff = new ArrayList<>(); comments = new HashSet<>(); addDomHandler(this, ClickEvent.getType()); } void init(CodeMirror cmB) { this.cmB = cmB; } void refresh() { update(cmB.getScrollInfo()); } void update(ScrollInfo si) { double viewHeight = si.getClientHeight(); double r = ratio(si); com.google.gwt.dom.client.Style style = viewport.getElement().getStyle(); style.setTop(si.getTop() * r, Unit.PX); style.setHeight(Math.max(10, viewHeight * r), Unit.PX); getElement().getStyle().setHeight(viewHeight, Unit.PX); for (MarkHandle info : diff) { info.position(r); } for (MarkHandle info : comments) { info.position(r); } } @Override protected void onUnload() { super.onUnload(); if (dragging) { DOM.releaseCapture(viewport.getElement()); } } @Override public void onClick(ClickEvent e) { if (e.getY() < viewport.getElement().getOffsetTop()) { CodeMirror.handleVimKey(cmB, "<PageUp>"); } else { CodeMirror.handleVimKey(cmB, "<PageDown>"); } cmB.focus(); } @UiHandler("viewport") void onMouseDown(MouseDownEvent e) { if (cmB != null) { dragging = true; ratio = ratio(cmB.getScrollInfo()); startY = e.getY(); viewport.addStyleName(style.viewportDrag()); DOM.setCapture(viewport.getElement()); e.preventDefault(); e.stopPropagation(); } } @UiHandler("viewport") void onMouseMove(MouseMoveEvent e) { if (dragging) { int y = e.getRelativeY(getElement()) - startY; cmB.scrollToY(Math.max(0, y / ratio)); e.preventDefault(); e.stopPropagation(); } } @UiHandler("viewport") void onMouseUp(MouseUpEvent e) { if (dragging) { dragging = false; DOM.releaseCapture(viewport.getElement()); viewport.removeStyleName(style.viewportDrag()); e.preventDefault(); e.stopPropagation(); } } private double ratio(ScrollInfo si) { double barHeight = si.getClientHeight(); double contentHeight = si.getHeight(); return barHeight / contentHeight; } MarkHandle add(CodeMirror cm, int line, int height, MarkType type) { MarkHandle mark = new MarkHandle(cm, line, height); switch (type) { case COMMENT: mark.addStyleName(style.comment()); comments.add(mark); break; case DRAFT: mark.addStyleName(style.draft()); mark.getElement().setInnerText("*"); comments.add(mark); break; case INSERT: mark.addStyleName(style.insert()); diff.add(mark); break; case DELETE: mark.addStyleName(style.delete()); diff.add(mark); break; case EDIT: mark.edit = DOM.createDiv(); mark.edit.setClassName(style.halfGutter()); mark.getElement().appendChild(mark.edit); mark.addStyleName(style.insert()); diff.add(mark); break; } if (cmB != null) { mark.position(ratio(cmB.getScrollInfo())); } ((HTMLPanel) getWidget()).add(mark); return mark; } void clearDiffMarkers() { for (MarkHandle mark : diff) { mark.removeFromParent(); } diff.clear(); } class MarkHandle extends Widget implements ClickHandler { private static final int MIN_HEIGHT = 3; private final CodeMirror cm; private final int line; private final int height; private Element edit; MarkHandle(CodeMirror cm, int line, int height) { this.cm = cm; this.line = line; this.height = height; setElement((Element) (DOM.createDiv())); setStyleName(style.gutter()); addDomHandler(this, ClickEvent.getType()); } void position(double ratio) { double y = cm.heightAtLine(line, "local"); getElement().getStyle().setTop(y * ratio, Unit.PX); if (height > 1) { double e = cm.heightAtLine(line + height, "local"); double h = Math.max(MIN_HEIGHT, (e - y) * ratio); getElement().getStyle().setHeight(h, Unit.PX); if (edit != null) { edit.getStyle().setHeight(h, Unit.PX); } } } @Override public void onClick(ClickEvent e) { if (height == 1 || !visible()) { e.stopPropagation(); double y = cm.heightAtLine(line, "local"); double viewport = cm.getScrollInfo().getClientHeight(); cm.setCursor(LineCharacter.create(line)); cm.scrollToY(y - 0.5 * viewport); cm.focus(); } } private boolean visible() { int markT = getElement().getOffsetTop(); int markE = markT + getElement().getOffsetHeight(); int viewT = viewport.getElement().getOffsetTop(); int viewE = viewT + viewport.getElement().getOffsetHeight(); return (viewT <= markT && markT < viewE) // mark top within viewport || (viewT <= markE && markE < viewE) // mark end within viewport || (markT <= viewT && viewE <= markE); // mark contains viewport } void remove() { removeFromParent(); comments.remove(this); } } }