react-native-view-shot/example/App.js

import React, { Component } from "react";
import {
  StyleSheet,
  Text,
  View,
  ScrollView,
  Image,
  Switch,
  TextInput,
  Picker,
  Slider,
  WebView
} from "react-native";
import omit from "lodash/omit";
import { captureRef, captureScreen } from "react-native-view-shot";
import { Surface } from "gl-react-native";
import GL from "gl-react";
import MapView from "react-native-maps";
import Video from "react-native-video";
import Btn from "./Btn";

const catsSource = {
  uri: "https://i.imgur.com/5EOyTDQ.jpg"
};

const shaders = GL.Shaders.create({
  helloGL: {
    frag: `
precision highp float;
varying vec2 uv;
uniform float blue;
void main () {
  gl_FragColor = vec4(uv.x, uv.y, blue, 1.0);
}`
  }
});

const HelloGL = GL.createComponent(
  ({ blue }) => <GL.Node shader={shaders.helloGL} uniforms={{ blue }} />,
  { displayName: "HelloGL" }
);

export default class App extends Component {
  state = {
    previewSource: catsSource,
    error: null,
    res: null,
    value: {
      format: "png",
      quality: 0.9,
      result: "tmpfile",
      snapshotContentContainer: false
    }
  };
  
  snapshot = refname => () =>
    (refname ? captureRef(this.refs[refname], this.state.value) : captureScreen(this.state.value))
      .then(
        res =>
          this.state.value.result !== "tmpfile"
            ? res
            : new Promise((success, failure) =>
                // just a test to ensure res can be used in Image.getSize
                Image.getSize(
                  res,
                  (width, height) => (
                    console.log(res, width, height), success(res)
                  ),
                  failure
                )
              )
      )
      .then(res =>
        this.setState({
          error: null,
          res,
          previewSource: {
            uri:
              this.state.value.result === "base64"
                ? "data:image/" + this.state.value.format + ";base64," + res
                : res
          }
        })
      )
      .catch(
        error => (
          console.warn(error),
          this.setState({ error, res: null, previewSource: null })
        )
      );

  render() {
    const { value, previewSource, error, res } = this.state;
    const {
      format,
      quality,
      width,
      height,
      result,
      snapshotContentContainer
    } = value;
    return (
      <ScrollView
        ref="full"
        style={styles.root}
        contentContainerStyle={styles.container}
      >
        <View ref="header" style={styles.header}>
          <Text style={styles.title}>😃 ViewShot Example 😜</Text>
          <View style={styles.p1}>
            <Text style={styles.text}>This is a </Text>
            <Text style={styles.code}>react-native-view-shot</Text>
            <Text style={styles.text}> showcase.</Text>
          </View>
          <View style={styles.preview}>
            {error ? (
              <Text style={styles.previewError}>
                {"" + (error.message || error)}
              </Text>
            ) : (
              <Image
                fadeDuration={0}
                resizeMode="contain"
                style={styles.previewImage}
                source={previewSource}
              />
            )}
          </View>
          <Text numberOfLines={1} style={styles.previewUriText}>
            {res ? res.slice(0, 200) : ""}
          </Text>
        </View>
        <View ref="form" style={styles.form}>
          <View style={styles.btns}>
            <Btn
              label="😻 Reset"
              onPress={() => this.setState({ previewSource: catsSource })}
            />
            <Btn label="📷 Head Section" onPress={this.snapshot("header")} />
            <Btn label="📷 Form" onPress={this.snapshot("form")} />
            <Btn
              label="📷 Experimental Section"
              onPress={this.snapshot("complex")}
            />
            <Btn label="📷 All (ScrollView)" onPress={this.snapshot("full")} />
            <Btn label="📷 GL React" onPress={this.snapshot("gl")} />
            <Btn label="📷 MapView" onPress={this.snapshot("mapview")} />
            <Btn label="📷 WebView" onPress={this.snapshot("webview")} />
            <Btn label="📷 Video" onPress={this.snapshot("video")} />
            <Btn label="📷 Native Screenshot" onPress={this.snapshot()}/>
            <Btn
              label="📷 Empty View (should crash)"
              onPress={this.snapshot("empty")}
            />
          </View>
          <View style={styles.field}>
            <Text style={styles.label}>Format</Text>
            <Picker
              style={styles.input}
              selectedValue={format}
              onValueChange={format =>
                this.setState({ value: { ...value, format } })}
            >
              <Picker.Item label="PNG" value="png" />
              <Picker.Item label="JPEG" value="jpeg" />
              <Picker.Item label="WEBM (android only)" value="webm" />
              <Picker.Item label="INVALID" value="_invalid_" />
            </Picker>
          </View>
          <View style={styles.field}>
            <Text style={styles.label}>Quality</Text>
            <Slider
              style={styles.input}
              value={quality}
              onValueChange={quality =>
                this.setState({ value: { ...value, quality } })}
            />
            <Text>{(quality * 100).toFixed(0)}%</Text>
          </View>
          <View style={styles.field}>
            <Text style={styles.label}>Size</Text>
            <Switch
              style={styles.switch}
              value={width !== undefined}
              onValueChange={checked =>
                this.setState({
                  value: omit(
                    {
                      ...value,
                      width: 300,
                      height: 300
                    },
                    checked ? [] : ["width", "height"]
                  )
                })}
            />
            {width !== undefined ? (
              <TextInput
                style={styles.inputText}
                value={"" + width}
                keyboardType="number-pad"
                onChangeText={txt =>
                  !isNaN(txt) &&
                  this.setState({
                    value: { ...value, width: parseInt(txt, 10) }
                  })}
              />
            ) : (
              <Text style={styles.inputText}>(auto)</Text>
            )}
            <Text>x</Text>
            {height !== undefined ? (
              <TextInput
                style={styles.inputText}
                value={"" + height}
                keyboardType="number-pad"
                onChangeText={txt =>
                  !isNaN(txt) &&
                  this.setState({
                    value: { ...value, height: parseInt(txt, 10) }
                  })}
              />
            ) : (
              <Text style={styles.inputText}>(auto)</Text>
            )}
          </View>
          <View style={styles.field}>
            <Text style={styles.label}>Result</Text>
            <Picker
              style={styles.input}
              selectedValue={result}
              onValueChange={result =>
                this.setState({ value: { ...value, result } })}
            >
              <Picker.Item label="tmpfile" value="tmpfile" />
              <Picker.Item label="base64" value="base64" />
              <Picker.Item label="data URI" value="data-uri" />
              <Picker.Item label="INVALID" value="_invalid_" />
            </Picker>
          </View>
          <View style={styles.field}>
            <Text style={styles.label}>snapshotContentContainer</Text>
            <Switch
              style={styles.switch}
              value={snapshotContentContainer}
              onValueChange={snapshotContentContainer =>
                this.setState({
                  value: { ...value, snapshotContentContainer }
                })}
            />
          </View>
        </View>
        <View ref="empty" collapsable={false} />
        <View style={styles.experimental} ref="complex" collapsable={false}>
          <Text style={styles.experimentalTitle}>Experimental Stuff</Text>
          <Surface ref="gl" width={300} height={300}>
            <HelloGL blue={0.5} />
          </Surface>
          <MapView
            ref="mapview"
            initialRegion={{
              latitude: 37.78825,
              longitude: -122.4324,
              latitudeDelta: 0.0922,
              longitudeDelta: 0.0421
            }}
            style={{ width: 300, height: 300 }}
          />
          <View
            ref="webview"
            collapsable={false}
            style={{ width: 300, height: 300 }}
          >
            <WebView
              source={{
                uri: "https://github.com/gre/react-native-view-shot"
              }}
            />
          </View>
          <Video
            ref="video"
            style={{ width: 300, height: 300 }}
            source={require("./broadchurch.mp4")}
            volume={0}
            repeat
          />
        </View>
      </ScrollView>
    );
  }
}

const styles = StyleSheet.create({
  root: {
    flex: 1,
    backgroundColor: "#f6f6f6"
  },
  container: {
    paddingVertical: 20,
    backgroundColor: "#f6f6f6"
  },
  title: {
    fontSize: 20,
    textAlign: "center",
    margin: 10
  },
  experimental: {
    padding: 10,
    flexDirection: "column",
    alignItems: "center"
  },
  experimentalTitle: {
    fontSize: 16,
    margin: 10
  },
  p1: {
    marginBottom: 10,
    flexDirection: "row",
    flexWrap: "wrap",
    justifyContent: "center",
    alignItems: "center"
  },
  text: {
    color: "#333"
  },
  code: {
    fontWeight: "bold",
    color: "#000"
  },
  field: {
    flexDirection: "row",
    alignItems: "center",
    paddingVertical: 4,
    paddingHorizontal: 10
  },
  label: {
    minWidth: 80,
    fontStyle: "italic",
    color: "#888"
  },
  switch: {
    marginRight: 50
  },
  input: {
    flex: 1,
    marginHorizontal: 5
  },
  inputText: {
    flex: 1,
    marginHorizontal: 5,
    color: "red",
    textAlign: "center"
  },
  preview: {
    flexDirection: "row",
    alignItems: "center",
    justifyContent: "space-around"
  },
  previewImage: {
    width: 375,
    height: 300
  },
  previewUriText: {
    fontSize: 12,
    fontStyle: "italic",
    color: "#666",
    textAlign: "center",
    padding: 10,
    paddingBottom: 0
  },
  previewError: {
    width: 375,
    height: 300,
    paddingTop: 20,
    textAlign: "center",
    fontSize: 20,
    fontWeight: "bold",
    color: "#fff",
    backgroundColor: "#c00"
  },
  header: {
    backgroundColor: "#f6f6f6",
    borderColor: "#000",
    borderWidth: 1,
    paddingBottom: 20
  },
  form: {
    backgroundColor: "#fff"
  },
  btns: {
    flexDirection: "row",
    flexWrap: "wrap",
    alignItems: "center",
    justifyContent: "center",
    paddingVertical: 10,
    margin: 4
  }
});