761 lines
28 KiB
JavaScript
761 lines
28 KiB
JavaScript
/**
|
|
* Copyright (c) 2013-present, Facebook, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This source code is licensed under the BSD-style license found in the
|
|
* LICENSE file in the root directory of this source tree. An additional grant
|
|
* of patent rights can be found in the PATENTS file in the same directory.
|
|
*
|
|
* Facebook, Inc. ("Facebook") owns all right, title and interest, including
|
|
* all intellectual property and other proprietary rights, in and to the React
|
|
* Native CustomComponents software (the "Software"). Subject to your
|
|
* compliance with these terms, you are hereby granted a non-exclusive,
|
|
* worldwide, royalty-free copyright license to (1) use and copy the Software;
|
|
* and (2) reproduce and distribute the Software as part of your own software
|
|
* ("Your Software"). Facebook reserves all rights not expressly granted to
|
|
* you in this license agreement.
|
|
*
|
|
* THE SOFTWARE AND DOCUMENTATION, IF ANY, ARE PROVIDED "AS IS" AND ANY EXPRESS
|
|
* OR IMPLIED WARRANTIES (INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE) ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL FACEBOOK OR ITS AFFILIATES, OFFICERS, DIRECTORS OR
|
|
* EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
|
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
|
|
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
|
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
|
|
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THE SOFTWARE, EVEN IF
|
|
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* @providesModule WindowedListView
|
|
* @flow
|
|
*/
|
|
'use strict';
|
|
|
|
const Batchinator = require('Batchinator');
|
|
const IncrementalGroup = require('IncrementalGroup');
|
|
const React = require('React');
|
|
const ScrollView = require('ScrollView');
|
|
const Set = require('Set');
|
|
const StyleSheet = require('StyleSheet');
|
|
const Systrace = require('Systrace');
|
|
const View = require('View');
|
|
const ViewabilityHelper = require('ViewabilityHelper');
|
|
|
|
const clamp = require('clamp');
|
|
const deepDiffer = require('deepDiffer');
|
|
const infoLog = require('infoLog');
|
|
const invariant = require('fbjs/lib/invariant');
|
|
const nullthrows = require('fbjs/lib/nullthrows');
|
|
|
|
import type ReactComponent from 'ReactComponent';
|
|
|
|
const DEBUG = false;
|
|
|
|
/**
|
|
* An experimental ListView implementation designed for efficient memory usage
|
|
* when rendering huge/infinite lists. It works by rendering a subset of rows
|
|
* and replacing offscreen rows with an empty spacer, which means that it has to
|
|
* re-render rows when scrolling back up.
|
|
*
|
|
* Note that rows must be the same height when they are re-mounted as when they
|
|
* are unmounted otherwise the content will jump around. This means that any
|
|
* state that affects the height, such as tap to expand, should be stored
|
|
* outside the row component to maintain continuity.
|
|
*
|
|
* This is not a drop-in replacement for `ListView` - many features are not
|
|
* supported, including section headers, dataSources, horizontal layout, etc.
|
|
*
|
|
* Row data should be provided as a simple array corresponding to rows. `===`
|
|
* is used to determine if a row has changed and should be re-rendered.
|
|
*
|
|
* Rendering is done incrementally one row at a time to minimize the amount of
|
|
* work done per JS event tick. Individual rows can also use <Incremental>
|
|
* to further break up the work and keep the app responsive and improve scroll
|
|
* perf if rows get exceedingly complex.
|
|
*
|
|
* Note that it's possible to scroll faster than rows can be rendered. Instead
|
|
* of showing the user a bunch of un-mounted blank space, WLV sets contentInset
|
|
* to prevent scrolling into unrendered areas. Supply the
|
|
* `renderWindowBoundaryIndicator` prop to indicate the boundary to the user,
|
|
* e.g. with a row placeholder.
|
|
*/
|
|
type Props = {
|
|
/**
|
|
* A simple array of data blobs that are passed to the renderRow function in
|
|
* order. Note there is no dataSource like in the standard `ListView`.
|
|
*/
|
|
data: Array<{rowKey: string, rowData: any}>,
|
|
/**
|
|
* Takes a data blob from the `data` array prop plus some meta info and should
|
|
* return a row.
|
|
*/
|
|
renderRow: (
|
|
rowData: any, sectionIdx: number, rowIdx: number, rowKey: string
|
|
) => ?ReactElement<any>,
|
|
/**
|
|
* Rendered when the list is scrolled faster than rows can be rendered.
|
|
*/
|
|
renderWindowBoundaryIndicator?: () => ?ReactElement<any>,
|
|
/**
|
|
* Always rendered at the bottom of all the rows.
|
|
*/
|
|
renderFooter?: () => ?ReactElement<any>,
|
|
/**
|
|
* Pipes through normal onScroll events from the underlying `ScrollView`.
|
|
*/
|
|
onScroll?: (event: Object) => void,
|
|
/**
|
|
* Called when the rows that are visible in the viewport change.
|
|
*/
|
|
onVisibleRowsChanged?: (firstIdx: number, count: number) => void,
|
|
/**
|
|
* Called when the viewability of rows changes, as defined by the
|
|
* `viewablePercentThreshold` prop.
|
|
*/
|
|
onViewableRowsChanged?: (viewableRows: Array<number>) => void,
|
|
/**
|
|
* The percent of a row that must be visible to consider it "viewable".
|
|
*/
|
|
viewablePercentThreshold: number,
|
|
/**
|
|
* Number of rows to render on first mount.
|
|
*/
|
|
initialNumToRender: number,
|
|
/**
|
|
* Maximum number of rows to render while scrolling, i.e. the window size.
|
|
*/
|
|
maxNumToRender: number,
|
|
/**
|
|
* Number of rows to render beyond the viewport. Note that this combined with
|
|
* `maxNumToRender` and the number of rows that can fit in one screen will
|
|
* determine how many rows to render above the viewport.
|
|
*/
|
|
numToRenderAhead: number,
|
|
/**
|
|
* Used to log perf events for async row rendering.
|
|
*/
|
|
asyncRowPerfEventName?: string,
|
|
/**
|
|
* A function that returns the scrollable component in which the list rows
|
|
* are rendered. Defaults to returning a ScrollView with the given props.
|
|
*/
|
|
renderScrollComponent: (props: ?Object) => ReactElement<any>,
|
|
/**
|
|
* Use to disable incremental rendering when not wanted, e.g. to speed up initial render.
|
|
*/
|
|
disableIncrementalRendering: boolean,
|
|
/**
|
|
* This determines how frequently events such as scroll and layout can trigger a re-render.
|
|
*/
|
|
recomputeRowsBatchingPeriod: number,
|
|
/**
|
|
* Called when rows will be mounted/unmounted. Mounted rows always form a contiguous block so it
|
|
* is expressed as a range of start plus count.
|
|
*/
|
|
onMountedRowsWillChange?: (firstIdx: number, count: number) => void,
|
|
/**
|
|
* Change this when you want to make sure the WindowedListView will re-render, for example when
|
|
* the result of `renderScrollComponent` might change. It will be compared in
|
|
* `shouldComponentUpdate`.
|
|
*/
|
|
shouldUpdateToken?: string,
|
|
};
|
|
|
|
type State = {
|
|
boundaryIndicatorHeight?: number,
|
|
firstRow: number,
|
|
lastRow: number,
|
|
};
|
|
class WindowedListView extends React.Component {
|
|
props: Props;
|
|
state: State;
|
|
/**
|
|
* Recomputing which rows to render is batched up and run asynchronously to avoid wastful updates,
|
|
* e.g. from multiple layout updates in rapid succession.
|
|
*/
|
|
_computeRowsToRenderBatcher: Batchinator;
|
|
_firstVisible: number = -1;
|
|
_lastVisible: number = -1;
|
|
_scrollOffsetY: number = 0;
|
|
_isScrolling: boolean = false;
|
|
_frameHeight: number = 0;
|
|
_rowFrames: {[key: string]: Object} = {};
|
|
_rowRenderMode: {[key: string]: null | 'async' | 'sync'} = {};
|
|
_rowFramesDirty: boolean = false;
|
|
_hasCalledOnEndReached: boolean = false;
|
|
_willComputeRowsToRender: boolean = false;
|
|
_viewableRows: Array<number> = [];
|
|
_cellsInProgress: Set<string> = new Set();
|
|
_scrollRef: ?Object;
|
|
|
|
static defaultProps = {
|
|
initialNumToRender: 10,
|
|
maxNumToRender: 30,
|
|
numToRenderAhead: 10,
|
|
viewablePercentThreshold: 50,
|
|
renderScrollComponent: (props) => <ScrollView {...props} />,
|
|
disableIncrementalRendering: false,
|
|
recomputeRowsBatchingPeriod: 10, // This should capture most events that happen within a frame
|
|
};
|
|
|
|
constructor(props: Props) {
|
|
super(props);
|
|
invariant(
|
|
this.props.numToRenderAhead < this.props.maxNumToRender,
|
|
'WindowedListView: numToRenderAhead must be less than maxNumToRender'
|
|
);
|
|
this._computeRowsToRenderBatcher = new Batchinator(
|
|
() => this._computeRowsToRender(this.props),
|
|
this.props.recomputeRowsBatchingPeriod,
|
|
);
|
|
this.state = {
|
|
firstRow: 0,
|
|
lastRow: Math.min(this.props.data.length, this.props.initialNumToRender) - 1,
|
|
};
|
|
}
|
|
getScrollResponder(): ?ReactComponent {
|
|
return this._scrollRef &&
|
|
this._scrollRef.getScrollResponder &&
|
|
this._scrollRef.getScrollResponder();
|
|
}
|
|
shouldComponentUpdate(newProps: Props, newState: State): boolean {
|
|
DEBUG && infoLog('WLV: shouldComponentUpdate...');
|
|
if (newState !== this.state) {
|
|
DEBUG && infoLog(' yes: ', {newState, oldState: this.state});
|
|
return true;
|
|
}
|
|
for (const key in newProps) {
|
|
if (key !== 'data' && newProps[key] !== this.props[key]) {
|
|
DEBUG && infoLog(' yes, non-data prop change: ', {key});
|
|
return true;
|
|
}
|
|
}
|
|
const newDataSubset = newProps.data.slice(newState.firstRow, newState.lastRow + 1);
|
|
const prevDataSubset = this.props.data.slice(this.state.firstRow, this.state.lastRow + 1);
|
|
if (newDataSubset.length !== prevDataSubset.length) {
|
|
DEBUG && infoLog(
|
|
' yes, subset length: ',
|
|
{newLen: newDataSubset.length, oldLen: prevDataSubset.length}
|
|
);
|
|
return true;
|
|
}
|
|
for (let idx = 0; idx < newDataSubset.length; idx++) {
|
|
if (newDataSubset[idx].rowData !== prevDataSubset[idx].rowData ||
|
|
newDataSubset[idx].rowKey !== prevDataSubset[idx].rowKey) {
|
|
DEBUG && infoLog(
|
|
' yes, data change: ',
|
|
{idx, new: newDataSubset[idx], old: prevDataSubset[idx]}
|
|
);
|
|
return true;
|
|
}
|
|
}
|
|
DEBUG && infoLog(' knope');
|
|
return false;
|
|
}
|
|
componentWillReceiveProps() {
|
|
this._computeRowsToRenderBatcher.schedule();
|
|
}
|
|
_onMomentumScrollEnd = (e: Object) => {
|
|
this._onScroll(e);
|
|
};
|
|
_onScroll = (e: Object) => {
|
|
const newScrollY = e.nativeEvent.contentOffset.y;
|
|
this._isScrolling = this._scrollOffsetY !== newScrollY;
|
|
this._scrollOffsetY = newScrollY;
|
|
this._frameHeight = e.nativeEvent.layoutMeasurement.height;
|
|
// We don't want to enqueue any updates if any cells are in the middle of an incremental render,
|
|
// because it would just be wasted work.
|
|
if (this._cellsInProgress.size === 0) {
|
|
this._computeRowsToRenderBatcher.schedule();
|
|
}
|
|
if (this.props.onViewableRowsChanged && Object.keys(this._rowFrames).length) {
|
|
const viewableRows = ViewabilityHelper.computeViewableRows(
|
|
this.props.viewablePercentThreshold,
|
|
this._rowFrames,
|
|
this.props.data,
|
|
e.nativeEvent.contentOffset.y,
|
|
e.nativeEvent.layoutMeasurement.height
|
|
);
|
|
if (deepDiffer(viewableRows, this._viewableRows)) {
|
|
this._viewableRows = viewableRows;
|
|
nullthrows(this.props.onViewableRowsChanged)(this._viewableRows);
|
|
}
|
|
}
|
|
this.props.onScroll && this.props.onScroll(e);
|
|
};
|
|
// Caller does the diffing so we don't have to.
|
|
_onNewLayout = (params: {rowKey: string, layout: Object}) => {
|
|
const {rowKey, layout} = params;
|
|
if (DEBUG) {
|
|
const prev = this._rowFrames[rowKey] || {};
|
|
infoLog(
|
|
'record layout for row: ',
|
|
{k: rowKey, h: layout.height, y: layout.y, x: layout.x, hp: prev.height, yp: prev.y}
|
|
);
|
|
if (this._rowFrames[rowKey]) {
|
|
const deltaY = Math.abs(this._rowFrames[rowKey].y - layout.y);
|
|
const deltaH = Math.abs(this._rowFrames[rowKey].height - layout.height);
|
|
if (deltaY > 2 || deltaH > 2) {
|
|
const dataEntry = this.props.data.find((datum) => datum.rowKey === rowKey);
|
|
console.warn(
|
|
'layout jump: ',
|
|
{dataEntry, prevLayout: this._rowFrames[rowKey], newLayout: layout}
|
|
);
|
|
}
|
|
}
|
|
}
|
|
this._rowFrames[rowKey] = {...layout, offscreenLayoutDone: true};
|
|
this._rowFramesDirty = true;
|
|
if (this._cellsInProgress.size === 0) {
|
|
this._computeRowsToRenderBatcher.schedule();
|
|
}
|
|
};
|
|
_onWillUnmountCell = (rowKey: string) => {
|
|
if (this._rowFrames[rowKey]) {
|
|
this._rowFrames[rowKey].offscreenLayoutDone = false;
|
|
this._rowRenderMode[rowKey] = null;
|
|
}
|
|
};
|
|
/**
|
|
* This is used to keep track of cells that are in the process of rendering. If any cells are in
|
|
* progress, then other updates are skipped because they will just be wasted work.
|
|
*/
|
|
_onProgressChange = ({rowKey, inProgress}: {rowKey: string, inProgress: boolean}) => {
|
|
if (inProgress) {
|
|
this._cellsInProgress.add(rowKey);
|
|
} else {
|
|
this._cellsInProgress.delete(rowKey);
|
|
}
|
|
};
|
|
componentWillUnmount() {
|
|
this._computeRowsToRenderBatcher.dispose();
|
|
}
|
|
_computeRowsToRender(props: Object): void {
|
|
const totalRows = props.data.length;
|
|
if (totalRows === 0) {
|
|
this._updateVisibleRows(-1, -1);
|
|
this.setState({
|
|
firstRow: 0,
|
|
lastRow: -1,
|
|
});
|
|
return;
|
|
}
|
|
const rowFrames = this._rowFrames;
|
|
let firstVisible = -1;
|
|
let lastVisible = 0;
|
|
let lastRow = clamp(0, this.state.lastRow, totalRows - 1);
|
|
const top = this._scrollOffsetY;
|
|
const bottom = top + this._frameHeight;
|
|
for (let idx = 0; idx < lastRow; idx++) {
|
|
const frame = rowFrames[props.data[idx].rowKey];
|
|
if (!frame) {
|
|
// No frame - sometimes happens when they come out of order, so just wait for the rest.
|
|
return;
|
|
}
|
|
if (((frame.y + frame.height) > top) && (firstVisible < 0)) {
|
|
firstVisible = idx;
|
|
}
|
|
if (frame.y < bottom) {
|
|
lastVisible = idx;
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
if (firstVisible === -1) {
|
|
firstVisible = 0;
|
|
}
|
|
this._updateVisibleRows(firstVisible, lastVisible);
|
|
|
|
// Unfortuantely, we can't use <Incremental> to simplify our increment logic in this function
|
|
// because we need to make sure that cells are rendered in the right order one at a time when
|
|
// scrolling back up.
|
|
|
|
const numRendered = lastRow - this.state.firstRow + 1;
|
|
// Our last row target that we will approach incrementally
|
|
const targetLastRow = clamp(
|
|
numRendered - 1, // Don't reduce numRendered when scrolling back up
|
|
lastVisible + props.numToRenderAhead, // Primary goal
|
|
totalRows - 1, // Don't render past the end
|
|
);
|
|
// Increment the last row one at a time per JS event loop
|
|
if (targetLastRow > this.state.lastRow) {
|
|
lastRow++;
|
|
} else if (targetLastRow < this.state.lastRow) {
|
|
lastRow--;
|
|
}
|
|
// Once last row is set, figure out the first row
|
|
const firstRow = Math.max(
|
|
0, // Don't render past the top
|
|
lastRow - props.maxNumToRender + 1, // Don't exceed max to render
|
|
lastRow - numRendered, // Don't render more than 1 additional row
|
|
);
|
|
if (lastRow >= totalRows) {
|
|
// It's possible that the number of rows decreased by more than one
|
|
// increment could compensate for. Need to make sure we don't render more
|
|
// than one new row at a time, but don't want to render past the end of
|
|
// the data.
|
|
lastRow = totalRows - 1;
|
|
}
|
|
if (props.onEndReached) {
|
|
// Make sure we call onEndReached exactly once every time we reach the
|
|
// end. Resets if scoll back up and down again.
|
|
const willBeAtTheEnd = lastRow === (totalRows - 1);
|
|
if (willBeAtTheEnd && !this._hasCalledOnEndReached) {
|
|
props.onEndReached();
|
|
this._hasCalledOnEndReached = true;
|
|
} else {
|
|
// If lastRow is changing, reset so we can call onEndReached again
|
|
this._hasCalledOnEndReached = this.state.lastRow === lastRow;
|
|
}
|
|
}
|
|
const rowsShouldChange = firstRow !== this.state.firstRow || lastRow !== this.state.lastRow;
|
|
if (this._rowFramesDirty || rowsShouldChange) {
|
|
if (rowsShouldChange) {
|
|
props.onMountedRowsWillChange &&
|
|
props.onMountedRowsWillChange(firstRow, lastRow - firstRow + 1);
|
|
infoLog(
|
|
'WLV: row render range will change:',
|
|
{firstRow, firstVis: this._firstVisible, lastVis: this._lastVisible, lastRow},
|
|
);
|
|
}
|
|
this._rowFramesDirty = false;
|
|
this.setState({firstRow, lastRow});
|
|
}
|
|
}
|
|
_updateVisibleRows(newFirstVisible: number, newLastVisible: number) {
|
|
if (this.props.onVisibleRowsChanged) {
|
|
if (this._firstVisible !== newFirstVisible ||
|
|
this._lastVisible !== newLastVisible) {
|
|
this.props.onVisibleRowsChanged(newFirstVisible, newLastVisible - newFirstVisible + 1);
|
|
}
|
|
}
|
|
this._firstVisible = newFirstVisible;
|
|
this._lastVisible = newLastVisible;
|
|
}
|
|
render(): ReactElement<any> {
|
|
const {firstRow} = this.state;
|
|
const lastRow = clamp(0, this.state.lastRow, this.props.data.length - 1);
|
|
const rowFrames = this._rowFrames;
|
|
const rows = [];
|
|
let spacerHeight = 0;
|
|
// Incremental rendering is a tradeoff between throughput and responsiveness. When we have
|
|
// plenty of buffer (say 50% of the target), we render incrementally to keep the app responsive.
|
|
// If we are dangerously low on buffer (say below 25%) we always disable incremental to try to
|
|
// catch up as fast as possible. In the middle, we only disable incremental while scrolling
|
|
// since it's unlikely the user will try to press a button while scrolling. We also ignore the
|
|
// "buffer" size when we are bumped up against the edge of the available data.
|
|
const firstBuffer = firstRow === 0 ? Infinity : this._firstVisible - firstRow;
|
|
const lastBuffer = lastRow === this.props.data.length - 1
|
|
? Infinity
|
|
: lastRow - this._lastVisible;
|
|
const minBuffer = Math.min(firstBuffer, lastBuffer);
|
|
const disableIncrementalRendering = this.props.disableIncrementalRendering ||
|
|
(this._isScrolling && minBuffer < this.props.numToRenderAhead * 0.5) ||
|
|
(minBuffer < this.props.numToRenderAhead * 0.25);
|
|
// Render mode is sticky while the component is mounted.
|
|
for (let ii = firstRow; ii <= lastRow; ii++) {
|
|
const rowKey = this.props.data[ii].rowKey;
|
|
if (
|
|
this._rowRenderMode[rowKey] === 'sync' ||
|
|
(disableIncrementalRendering && this._rowRenderMode[rowKey] !== 'async')
|
|
) {
|
|
this._rowRenderMode[rowKey] = 'sync';
|
|
} else {
|
|
this._rowRenderMode[rowKey] = 'async';
|
|
}
|
|
}
|
|
for (let ii = firstRow; ii <= lastRow; ii++) {
|
|
const rowKey = this.props.data[ii].rowKey;
|
|
if (!rowFrames[rowKey]) {
|
|
break; // if rowFrame missing, no following ones will exist so quit early
|
|
}
|
|
// Look for the first row where offscreen layout is done (only true for mounted rows) or it
|
|
// will be rendered synchronously and set the spacer height such that it will offset all the
|
|
// unmounted rows before that one using the saved frame data.
|
|
if (rowFrames[rowKey].offscreenLayoutDone || this._rowRenderMode[rowKey] === 'sync') {
|
|
if (ii > 0) {
|
|
const prevRowKey = this.props.data[ii - 1].rowKey;
|
|
const frame = rowFrames[prevRowKey];
|
|
spacerHeight = frame ? frame.y + frame.height : 0;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
let showIndicator = false;
|
|
if (
|
|
spacerHeight > (this.state.boundaryIndicatorHeight || 0) &&
|
|
this.props.renderWindowBoundaryIndicator
|
|
) {
|
|
showIndicator = true;
|
|
spacerHeight -= this.state.boundaryIndicatorHeight || 0;
|
|
}
|
|
DEBUG && infoLog('render top spacer with height ', spacerHeight);
|
|
rows.push(<View key="sp-top" style={{height: spacerHeight}} />);
|
|
if (this.props.renderWindowBoundaryIndicator) {
|
|
// Always render it, even if removed, so that we can get the height right away and don't waste
|
|
// time creating/ destroying it. Should see if there is a better spinner option that is not as
|
|
// expensive.
|
|
rows.push(
|
|
<View
|
|
style={!showIndicator && styles.remove}
|
|
key="ind-top"
|
|
onLayout={(e) => {
|
|
const layout = e.nativeEvent.layout;
|
|
if (layout.height !== this.state.boundaryIndicatorHeight) {
|
|
this.setState({boundaryIndicatorHeight: layout.height});
|
|
}
|
|
}}>
|
|
{this.props.renderWindowBoundaryIndicator(showIndicator)}
|
|
</View>
|
|
);
|
|
}
|
|
for (let idx = firstRow; idx <= lastRow; idx++) {
|
|
const rowKey = this.props.data[idx].rowKey;
|
|
const includeInLayout = this._rowRenderMode[rowKey] === 'sync' ||
|
|
(this._rowFrames[rowKey] && this._rowFrames[rowKey].offscreenLayoutDone);
|
|
rows.push(
|
|
<CellRenderer
|
|
key={rowKey}
|
|
rowKey={rowKey}
|
|
rowIndex={idx}
|
|
onNewLayout={this._onNewLayout}
|
|
onWillUnmount={this._onWillUnmountCell}
|
|
includeInLayout={includeInLayout}
|
|
onProgressChange={this._onProgressChange}
|
|
asyncRowPerfEventName={this.props.asyncRowPerfEventName}
|
|
rowData={this.props.data[idx].rowData}
|
|
renderRow={this.props.renderRow}
|
|
/>
|
|
);
|
|
}
|
|
const lastRowKey = this.props.data[lastRow].rowKey;
|
|
const showFooter = this._rowFrames[lastRowKey] &&
|
|
this._rowFrames[lastRowKey].offscreenLayoutDone &&
|
|
lastRow === this.props.data.length - 1;
|
|
if (this.props.renderFooter) {
|
|
rows.push(
|
|
<View
|
|
key="ind-footer"
|
|
style={showFooter ? styles.include : styles.remove}>
|
|
{this.props.renderFooter(showFooter)}
|
|
</View>
|
|
);
|
|
}
|
|
if (this.props.renderWindowBoundaryIndicator) {
|
|
rows.push(
|
|
<View
|
|
key="ind-bot"
|
|
style={showFooter ? styles.remove : styles.include}
|
|
onLayout={(e) => {
|
|
const layout = e.nativeEvent.layout;
|
|
if (layout.height !== this.state.boundaryIndicatorHeight) {
|
|
this.setState({boundaryIndicatorHeight: layout.height});
|
|
}
|
|
}}>
|
|
{this.props.renderWindowBoundaryIndicator(!showFooter)}
|
|
</View>
|
|
);
|
|
}
|
|
// Prevent user from scrolling into empty space of unmounted rows.
|
|
const contentInset = {top: firstRow === 0 ? 0 : -spacerHeight};
|
|
return (
|
|
this.props.renderScrollComponent({
|
|
scrollEventThrottle: 50,
|
|
removeClippedSubviews: true,
|
|
...this.props,
|
|
contentInset,
|
|
ref: (ref) => { this._scrollRef = ref; },
|
|
onScroll: this._onScroll,
|
|
onMomentumScrollEnd: this._onMomentumScrollEnd,
|
|
children: rows,
|
|
})
|
|
);
|
|
}
|
|
}
|
|
|
|
// performance testing id, unique for each component mount cycle
|
|
let g_perf_update_id = 0;
|
|
|
|
type CellProps = {
|
|
/**
|
|
* Row-specific data passed to renderRow and used in shouldComponentUpdate with ===
|
|
*/
|
|
rowData: mixed,
|
|
rowKey: string,
|
|
/**
|
|
* Renders the actual row contents.
|
|
*/
|
|
renderRow: (
|
|
rowData: mixed, sectionIdx: number, rowIdx: number, rowKey: string
|
|
) => ?ReactElement<any>,
|
|
/**
|
|
* Index of the row, passed through to other callbacks.
|
|
*/
|
|
rowIndex: number,
|
|
/**
|
|
* Used for marking async begin/end events for row rendering.
|
|
*/
|
|
asyncRowPerfEventName: ?string,
|
|
/**
|
|
* Initially false to indicate the cell should be rendered "offscreen" with position: absolute so
|
|
* that incremental rendering doesn't cause things to jump around. Once onNewLayout is called
|
|
* after offscreen rendering has completed, includeInLayout will be set true and the finished cell
|
|
* can be dropped into place.
|
|
*
|
|
* This is coordinated outside this component so the parent can syncronize this re-render with
|
|
* managing the placeholder sizing.
|
|
*/
|
|
includeInLayout: boolean,
|
|
/**
|
|
* Updates the parent with the latest layout. Only called when incremental rendering is done and
|
|
* triggers the parent to re-render this row with includeInLayout true.
|
|
*/
|
|
onNewLayout: (params: {rowKey: string, layout: Object}) => void,
|
|
/**
|
|
* Used to track when rendering is in progress so the parent can avoid wastedful re-renders that
|
|
* are just going to be invalidated once the cell finishes.
|
|
*/
|
|
onProgressChange: (progress: {rowKey: string, inProgress: boolean}) => void,
|
|
/**
|
|
* Used to invalidate the layout so the parent knows it needs to compensate for the height in the
|
|
* placeholder size.
|
|
*/
|
|
onWillUnmount: (rowKey: string) => void,
|
|
};
|
|
class CellRenderer extends React.Component {
|
|
props: CellProps;
|
|
_containerRef: View;
|
|
_offscreenRenderDone = false;
|
|
_timeout = 0;
|
|
_lastLayout: ?Object = null;
|
|
_perfUpdateID: number = 0;
|
|
_asyncCookie: any;
|
|
_includeInLayoutLatch: boolean = false;
|
|
componentWillMount() {
|
|
if (this.props.asyncRowPerfEventName) {
|
|
this._perfUpdateID = g_perf_update_id++;
|
|
this._asyncCookie = Systrace.beginAsyncEvent(
|
|
this.props.asyncRowPerfEventName + this._perfUpdateID
|
|
);
|
|
// $FlowFixMe(>=0.28.0)
|
|
infoLog(`perf_asynctest_${this.props.asyncRowPerfEventName}_start ${this._perfUpdateID} ` +
|
|
`${Date.now()}`);
|
|
}
|
|
if (this.props.includeInLayout) {
|
|
this._includeInLayoutLatch = true;
|
|
}
|
|
this.props.onProgressChange({rowKey: this.props.rowKey, inProgress: true});
|
|
}
|
|
_onLayout = (e) => {
|
|
const layout = e.nativeEvent.layout;
|
|
const layoutChanged = deepDiffer(this._lastLayout, layout);
|
|
this._lastLayout = layout;
|
|
if (!this._offscreenRenderDone || !layoutChanged) {
|
|
return; // Don't send premature or duplicate updates
|
|
}
|
|
this.props.onNewLayout({
|
|
rowKey: this.props.rowKey,
|
|
layout,
|
|
});
|
|
};
|
|
_updateParent() {
|
|
invariant(!this._offscreenRenderDone, 'should only finish rendering once');
|
|
this._offscreenRenderDone = true;
|
|
|
|
// If this is not called before calling onNewLayout, the number of inProgress cells will remain
|
|
// non-zero, and thus the onNewLayout call will not fire the needed state change update.
|
|
this.props.onProgressChange({rowKey: this.props.rowKey, inProgress: false});
|
|
|
|
// If an onLayout event hasn't come in yet, then we skip here and assume it will come in later.
|
|
// This happens when Incremental is disabled and _onOffscreenRenderDone is called faster than
|
|
// layout can happen.
|
|
this._lastLayout &&
|
|
this.props.onNewLayout({rowKey: this.props.rowKey, layout: this._lastLayout});
|
|
|
|
DEBUG && infoLog('\n >>>>> display row ' + this.props.rowIndex + '\n\n\n');
|
|
if (this.props.asyncRowPerfEventName) {
|
|
// Note this doesn't include the native render time but is more accurate than also including
|
|
// the JS render time of anything that has been queued up.
|
|
Systrace.endAsyncEvent(
|
|
this.props.asyncRowPerfEventName + this._perfUpdateID,
|
|
this._asyncCookie
|
|
);
|
|
// $FlowFixMe(>=0.28.0)
|
|
infoLog(`perf_asynctest_${this.props.asyncRowPerfEventName}_end ${this._perfUpdateID} ` +
|
|
`${Date.now()}`);
|
|
}
|
|
}
|
|
_onOffscreenRenderDone = () => {
|
|
DEBUG && infoLog('_onOffscreenRenderDone for row ' + this.props.rowIndex);
|
|
if (this._includeInLayoutLatch) {
|
|
this._updateParent(); // rendered straight into layout, so no need to flush
|
|
} else {
|
|
this._timeout = setTimeout(() => this._updateParent(), 1); // Flush any pending layout events.
|
|
}
|
|
};
|
|
componentWillUnmount() {
|
|
clearTimeout(this._timeout);
|
|
this.props.onProgressChange({rowKey: this.props.rowKey, inProgress: false});
|
|
this.props.onWillUnmount(this.props.rowKey);
|
|
}
|
|
componentWillReceiveProps(newProps) {
|
|
if (newProps.includeInLayout && !this.props.includeInLayout) {
|
|
invariant(this._offscreenRenderDone, 'Should never try to add to layout before render done');
|
|
this._includeInLayoutLatch = true; // Once we render in layout, make sure it sticks.
|
|
this._containerRef.setNativeProps({style: styles.include});
|
|
}
|
|
}
|
|
shouldComponentUpdate(newProps: CellProps) {
|
|
return newProps.rowData !== this.props.rowData;
|
|
}
|
|
_setRef = (ref) => {
|
|
this._containerRef = ref;
|
|
};
|
|
render() {
|
|
let debug;
|
|
if (DEBUG) {
|
|
infoLog('render cell ' + this.props.rowIndex);
|
|
const Text = require('Text');
|
|
debug = <Text style={{backgroundColor: 'lightblue'}}>
|
|
Row: {this.props.rowIndex}
|
|
</Text>;
|
|
}
|
|
const style = this._includeInLayoutLatch ? styles.include : styles.remove;
|
|
return (
|
|
<IncrementalGroup
|
|
disabled={this._includeInLayoutLatch}
|
|
onDone={this._onOffscreenRenderDone}
|
|
name={`WLVCell_${this.props.rowIndex}`}>
|
|
<View
|
|
ref={this._setRef}
|
|
style={style}
|
|
onLayout={this._onLayout}>
|
|
{debug}
|
|
{this.props.renderRow(this.props.rowData, 0, this.props.rowIndex, this.props.rowKey)}
|
|
{debug}
|
|
</View>
|
|
</IncrementalGroup>
|
|
);
|
|
}
|
|
}
|
|
|
|
const removedXOffset = DEBUG ? 123 : 0;
|
|
|
|
const styles = StyleSheet.create({
|
|
include: {
|
|
position: 'relative',
|
|
left: 0,
|
|
right: 0,
|
|
opacity: 1,
|
|
},
|
|
remove: {
|
|
position: 'absolute',
|
|
left: removedXOffset,
|
|
right: -removedXOffset,
|
|
opacity: DEBUG ? 0.1 : 0,
|
|
},
|
|
});
|
|
|
|
module.exports = WindowedListView;
|