(31)-访问相册API

CameraRoll

方法

实例

"use strict";

var React = require("react-native");
var {
  CameraRoll,
  Image,
  SliderIOS,
  StyleSheet,
  SwitchIOS,
  Text,
  View,
  TouchableOpacity
} = React;

var CameraRollView = require("./CameraRollView.ios");
var AssetScaledImageExampleView = require("./AssetScaledImageExample");

var CAMERA_ROLL_VIEW = "camera_roll_view";

var CameraRollExample = React.createClass({

  getInitialState() {
    return {
      groupTypes: "SavedPhotos",
      sliderValue: 1,
      bigImages: true,
    };
  },

  render() {
    return (
      <View>
        <SwitchIOS
          onValueChange={this._onSwitchChange}
          value={this.state.bigImages} />
        <Text>{(this.state.bigImages ? "Big" : "Small") + " Images"}</Text>
        <SliderIOS
          value={this.state.sliderValue}
          onValueChange={this._onSliderChange}
        />
        <Text>{"Group Type: " + this.state.groupTypes}</Text>
        <CameraRollView
          ref={CAMERA_ROLL_VIEW}
          batchSize={20}
          groupTypes={this.state.groupTypes}
          renderImage={this._renderImage}
        />
      </View>
    );
  },

  loadAsset(asset){
    this.props.navigator.push({
      title: "Camera Roll Image",
      component: AssetScaledImageExampleView,
      backButtonTitle: "Back",
      passProps: { asset: asset },
    });
  },

  _renderImage(asset) {
    var imageSize = this.state.bigImages ? 150 : 75;
    var imageStyle = [styles.image, {width: imageSize, height: imageSize}];
    var location = asset.node.location.longitude ?
      JSON.stringify(asset.node.location) : "Unknown location";
    return (
      <TouchableOpacity onPress={ this.loadAsset.bind( this, asset ) }>
        <View key={asset} style={styles.row}>
          <Image
            source={asset.node.image}
            style={imageStyle}
          />
          <View style={styles.info}>
            <Text style={styles.url}>{asset.node.image.uri}</Text>
            <Text>{location}</Text>
            <Text>{asset.node.group_name}</Text>
            <Text>{new Date(asset.node.timestamp).toString()}</Text>
          </View>
        </View>
      </TouchableOpacity>
    );
  },

  _onSliderChange(value) {
    var options = CameraRoll.GroupTypesOptions;
    var index = Math.floor(value * options.length * 0.99);
    var groupTypes = options[index];
    if (groupTypes !== this.state.groupTypes) {
      this.setState({groupTypes: groupTypes});
    }
  },

  _onSwitchChange(value) {
    this.refs[CAMERA_ROLL_VIEW].rendererChanged();
    this.setState({ bigImages: value });
  }
});

var styles = StyleSheet.create({
  row: {
    flexDirection: "row",
    flex: 1,
  },
  url: {
    fontSize: 9,
    marginBottom: 14,
  },
  image: {
    margin: 4,
  },
  info: {
    flex: 1,
  },
});

exports.title = "Camera Roll";
exports.description = "Example component that uses CameraRoll to list user"s photos";
exports.examples = [
  {
    title: "Photos",
    render(): ReactElement { return <CameraRollExample />; }
  }
];

效果