Wyatt Allen b8a8ededce Do not set focus on cursor target following diff scroll
The diff cursor suspends the underlying cursor's scroll behavior while
the diff is rendering if the user scrolls the page before the render is
complete. However, when focus-on-move is enabled, the underlying cursor
also sets focus and this causes a scroll anyway. With this change the
cursor manager suspends the focus-on-move in the same way that it
suspends the scroll behavior to prevent this unwanted scroll/focus.

Bug: Issue 7390
Change-Id: I2bc7a06e940475b6b3c94995494f4207902acb40
2017-10-17 11:56:36 -07:00

415 lines
11 KiB
JavaScript

// Copyright (C) 2016 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.
(function() {
'use strict';
const DiffSides = {
LEFT: 'left',
RIGHT: 'right',
};
const DiffViewMode = {
SIDE_BY_SIDE: 'SIDE_BY_SIDE',
UNIFIED: 'UNIFIED_DIFF',
};
const ScrollBehavior = {
KEEP_VISIBLE: 'keep-visible',
NEVER: 'never',
};
const LEFT_SIDE_CLASS = 'target-side-left';
const RIGHT_SIDE_CLASS = 'target-side-right';
Polymer({
is: 'gr-diff-cursor',
properties: {
/**
* Either DiffSides.LEFT or DiffSides.RIGHT.
*/
side: {
type: String,
value: DiffSides.RIGHT,
},
/** @type {!HTMLElement|undefined} */
diffRow: {
type: Object,
notify: true,
observer: '_rowChanged',
},
/**
* The diff views to cursor through and listen to.
*/
diffs: {
type: Array,
value() { return []; },
},
/**
* If set, the cursor will attempt to move to the line number (instead of
* the first chunk) the next time the diff renders. It is set back to null
* when used.
*
* @type (?number)
*/
initialLineNumber: {
type: Number,
value: null,
},
/**
* The scroll behavior for the cursor. Values are 'never' and
* 'keep-visible'. 'keep-visible' will only scroll if the cursor is beyond
* the viewport.
*/
_scrollBehavior: {
type: String,
value: ScrollBehavior.KEEP_VISIBLE,
},
_focusOnMove: {
type: Boolean,
value: true,
},
_listeningForScroll: Boolean,
},
observers: [
'_updateSideClass(side)',
'_diffsChanged(diffs.splices)',
],
attached() {
// Catch when users are scrolling as the view loads.
this.listen(window, 'scroll', '_handleWindowScroll');
},
detached() {
this.unlisten(window, 'scroll', '_handleWindowScroll');
},
moveLeft() {
this.side = DiffSides.LEFT;
if (this._isTargetBlank()) {
this.moveUp();
}
},
moveRight() {
this.side = DiffSides.RIGHT;
if (this._isTargetBlank()) {
this.moveUp();
}
},
moveDown() {
if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE) {
this.$.cursorManager.next(this._rowHasSide.bind(this));
} else {
this.$.cursorManager.next();
}
},
moveUp() {
if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE) {
this.$.cursorManager.previous(this._rowHasSide.bind(this));
} else {
this.$.cursorManager.previous();
}
},
moveToNextChunk() {
this.$.cursorManager.next(this._isFirstRowOfChunk.bind(this),
target => {
return target.parentNode.scrollHeight;
});
this._fixSide();
},
moveToPreviousChunk() {
this.$.cursorManager.previous(this._isFirstRowOfChunk.bind(this));
this._fixSide();
},
moveToNextCommentThread() {
this.$.cursorManager.next(this._rowHasThread.bind(this));
this._fixSide();
},
moveToPreviousCommentThread() {
this.$.cursorManager.previous(this._rowHasThread.bind(this));
this._fixSide();
},
/**
* @param {number} number
* @param {string} side
* @param {string=} opt_path
*/
moveToLineNumber(number, side, opt_path) {
const row = this._findRowByNumberAndFile(number, side, opt_path);
if (row) {
this.side = side;
this.$.cursorManager.setCursor(row);
}
},
/**
* Get the line number element targeted by the cursor row and side.
* @return {?Element|undefined}
*/
getTargetLineElement() {
let lineElSelector = '.lineNum';
if (!this.diffRow) {
return;
}
if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE) {
lineElSelector += this.side === DiffSides.LEFT ? '.left' : '.right';
}
return this.diffRow.querySelector(lineElSelector);
},
getTargetDiffElement() {
// Find the parent diff element of the cursor row.
for (let diff = this.diffRow; diff; diff = diff.parentElement) {
if (diff.tagName === 'GR-DIFF') { return diff; }
}
return null;
},
moveToFirstChunk() {
this.$.cursorManager.moveToStart();
this.moveToNextChunk();
},
reInitCursor() {
this._updateStops();
if (this.initialLineNumber) {
this.moveToLineNumber(this.initialLineNumber, this.side);
this.initialLineNumber = null;
} else {
this.moveToFirstChunk();
}
},
_handleWindowScroll() {
if (this._listeningForScroll) {
this._scrollBehavior = ScrollBehavior.NEVER;
this._focusOnMove = false;
this._listeningForScroll = false;
}
},
handleDiffUpdate() {
this._updateStops();
if (!this.diffRow) {
this.reInitCursor();
}
this._scrollBehavior = ScrollBehavior.KEEP_VISIBLE;
this._focusOnMove = true;
this._listeningForScroll = false;
},
_handleDiffRenderStart() {
this._listeningForScroll = true;
},
/**
* Get an object describing the location of the cursor. Such as
* {leftSide: false, number: 123} for line 123 of the revision, or
* {leftSide: true, number: 321} for line 321 of the base patch.
* Returns null if an address is not available.
* @return {?Object}
*/
getAddress() {
if (!this.diffRow) { return null; }
// Get the line-number cell targeted by the cursor. If the mode is unified
// then prefer the revision cell if available.
let cell;
if (this._getViewMode() === DiffViewMode.UNIFIED) {
cell = this.diffRow.querySelector('.lineNum.right');
if (!cell) {
cell = this.diffRow.querySelector('.lineNum.left');
}
} else {
cell = this.diffRow.querySelector('.lineNum.' + this.side);
}
if (!cell) { return null; }
const number = cell.getAttribute('data-value');
if (!number || number === 'FILE') { return null; }
return {
leftSide: cell.matches('.left'),
number: parseInt(number, 10),
};
},
_getViewMode() {
if (!this.diffRow) {
return null;
}
if (this.diffRow.classList.contains('side-by-side')) {
return DiffViewMode.SIDE_BY_SIDE;
} else {
return DiffViewMode.UNIFIED;
}
},
_rowHasSide(row) {
const selector = (this.side === DiffSides.LEFT ? '.left' : '.right') +
' + .content';
return !!row.querySelector(selector);
},
_isFirstRowOfChunk(row) {
const parentClassList = row.parentNode.classList;
return parentClassList.contains('section') &&
parentClassList.contains('delta') &&
!row.previousSibling;
},
_rowHasThread(row) {
return row.querySelector('gr-diff-comment-thread');
},
/**
* If we jumped to a row where there is no content on the current side then
* switch to the alternate side.
*/
_fixSide() {
if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE &&
this._isTargetBlank()) {
this.side = this.side === DiffSides.LEFT ?
DiffSides.RIGHT : DiffSides.LEFT;
}
},
_isTargetBlank() {
if (!this.diffRow) {
return false;
}
const actions = this._getActionsForRow();
return (this.side === DiffSides.LEFT && !actions.left) ||
(this.side === DiffSides.RIGHT && !actions.right);
},
_rowChanged(newRow, oldRow) {
if (oldRow) {
oldRow.classList.remove(LEFT_SIDE_CLASS, RIGHT_SIDE_CLASS);
}
this._updateSideClass();
},
_updateSideClass() {
if (!this.diffRow) {
return;
}
this.toggleClass(LEFT_SIDE_CLASS, this.side === DiffSides.LEFT,
this.diffRow);
this.toggleClass(RIGHT_SIDE_CLASS, this.side === DiffSides.RIGHT,
this.diffRow);
},
_isActionType(type) {
return type !== 'blank' && type !== 'contextControl';
},
_getActionsForRow() {
const actions = {left: false, right: false};
if (this.diffRow) {
actions.left = this._isActionType(
this.diffRow.getAttribute('left-type'));
actions.right = this._isActionType(
this.diffRow.getAttribute('right-type'));
}
return actions;
},
_getStops() {
return this.diffs.reduce(
(stops, diff) => {
return stops.concat(diff.getCursorStops());
}, []);
},
_updateStops() {
this.$.cursorManager.stops = this._getStops();
},
/**
* Setup and tear down on-render listeners for any diffs that are added or
* removed from the cursor.
* @private
*/
_diffsChanged(changeRecord) {
if (!changeRecord) { return; }
this._updateStops();
let splice;
let i;
for (let spliceIdx = 0;
changeRecord.indexSplices &&
spliceIdx < changeRecord.indexSplices.length;
spliceIdx++) {
splice = changeRecord.indexSplices[spliceIdx];
for (i = splice.index;
i < splice.index + splice.addedCount;
i++) {
this.listen(this.diffs[i], 'render-start', '_handleDiffRenderStart');
this.listen(this.diffs[i], 'render-content', 'handleDiffUpdate');
}
for (i = 0;
i < splice.removed && splice.removed.length;
i++) {
this.unlisten(splice.removed[i],
'render-start', '_handleDiffRenderStart');
this.unlisten(splice.removed[i],
'render-content', 'handleDiffUpdate');
}
}
},
_findRowByNumberAndFile(targetNumber, side, opt_path) {
let stops;
if (opt_path) {
const diff = this.diffs.filter(diff => diff.path === opt_path)[0];
stops = diff.getCursorStops();
} else {
stops = this.$.cursorManager.stops;
}
let selector;
for (let i = 0; i < stops.length; i++) {
selector = '.lineNum.' + side + '[data-value="' + targetNumber + '"]';
if (stops[i].querySelector(selector)) {
return stops[i];
}
}
},
});
})();