Improving image open time (#185)

* Moving intro into its own component

* Tidying JSX, and allowing image to render before first compression. Fixes #164.

src/components/App/index.tsx

@@ -38,6 +38,7 @@ import {
 
 import { decodeImage } from '../../codecs/decoders';
 import { cleanMerge, cleanSet } from '../../lib/clean-modify';
+import Intro from '../intro';
 
 type Orientation = 'horizontal' | 'vertical';
 
@@ -209,14 +210,6 @@ export default class App extends Component<Props, State> {
     }
   }
 
-  @bind
-  async onFileChange(event: Event): Promise<void> {
-    const fileInput = event.target as HTMLInputElement;
-    const file = fileInput.files && fileInput.files[0];
-    if (!file) return;
-    await this.updateFile(file);
-  }
-
   @bind
   async onFileDrop(event: FileDropEvent) {
     const { file } = event;
@@ -342,38 +335,38 @@ export default class App extends Component<Props, State> {
     return (
       <file-drop accept="image/*" onfiledrop={this.onFileDrop}>
         <div id="app" class={`${style.app} ${style[orientation]}`}>
-          {(leftImageData && rightImageData && source) ? (
-            <Output
-              orientation={orientation}
-              imgWidth={source.data.width}
-              imgHeight={source.data.height}
-              leftImg={leftImageData}
-              rightImg={rightImageData}
-              leftImgContain={leftImage.preprocessorState.resize.fitMethod === 'cover'}
-              rightImgContain={rightImage.preprocessorState.resize.fitMethod === 'cover'}
-            />
-          ) : (
-            <div class={style.welcome}>
-              <h1>Drop, paste or select an image</h1>
-              <input type="file" onChange={this.onFileChange} />
-            </div>
-          )}
-          {(leftImageData && rightImageData && source) && images.map((image, index) => (
-            <Options
-              orientation={orientation}
-              sourceAspect={source.data.width / source.data.height}
-              imageIndex={index}
-              imageFile={image.file}
-              sourceImageFile={source && source.file}
-              downloadUrl={image.downloadUrl}
-              preprocessorState={image.preprocessorState}
-              encoderState={image.encoderState}
-              onEncoderTypeChange={this.onEncoderTypeChange.bind(this, index)}
-              onEncoderOptionsChange={this.onEncoderOptionsChange.bind(this, index)}
-              onPreprocessorOptionsChange={this.onPreprocessorOptionsChange.bind(this, index)}
-              onCopyToOtherClick={this.onCopyToOtherClick.bind(this, index)}
-            />
-          ))}
+          {source
+            ?
+              <div class={`${style.optionPair} ${style[orientation]}`}>
+                <Output
+                  orientation={orientation}
+                  imgWidth={source.data.width}
+                  imgHeight={source.data.height}
+                  leftImg={leftImageData || source.data}
+                  rightImg={rightImageData || source.data}
+                  leftImgContain={leftImage.preprocessorState.resize.fitMethod === 'cover'}
+                  rightImgContain={rightImage.preprocessorState.resize.fitMethod === 'cover'}
+                />
+                {images.map((image, index) => (
+                  <Options
+                    orientation={orientation}
+                    sourceAspect={source.data.width / source.data.height}
+                    imageIndex={index}
+                    imageFile={image.file}
+                    sourceImageFile={source && source.file}
+                    downloadUrl={image.downloadUrl}
+                    preprocessorState={image.preprocessorState}
+                    encoderState={image.encoderState}
+                    onEncoderTypeChange={this.onEncoderTypeChange.bind(this, index)}
+                    onEncoderOptionsChange={this.onEncoderOptionsChange.bind(this, index)}
+                    onPreprocessorOptionsChange={this.onPreprocessorOptionsChange.bind(this, index)}
+                    onCopyToOtherClick={this.onCopyToOtherClick.bind(this, index)}
+                  />
+                ))}
+              </div>
+            :
+              <Intro onFile={this.updateFile} />
+          }
           {anyLoading && <span style={{ position: 'fixed', top: 0, left: 0 }}>Loading...</span>}
           <snack-bar ref={linkRef(this, 'snackbar')} />
         </div>

src/components/App/style.scss

@@ -11,39 +11,6 @@ Note: These styles are temporary. They will be replaced before going live.
   overflow: hidden;
   contain: strict;
   display: flex;
-  justify-content: flex-end;
-
-  &.horizontal {
-    justify-content: space-between;
-    align-items: flex-end;
-  }
-
-  &.vertical {
-    flex-direction: column;
-  }
-}
-
-.welcome {
-  margin: auto;
-  text-align: center;
-
-  h1 {
-    font-weight: inherit;
-    font-size: 150%;
-    text-align: center;
-  }
-
-  input {
-    display: inline-block;
-    width: 16em;
-    padding: 10px;
-    margin: 0 auto;
-    -webkit-appearance: none;
-    border: 1px solid var(--button-fg);
-    background: rgba(var(--button-fg-color), 0.1);
-    border-radius: 3px;
-    cursor: pointer;
-  }
 }
 
 :global {
@@ -87,3 +54,18 @@ Note: These styles are temporary. They will be replaced before going live.
     }
   }
 }
+
+.option-pair {
+  display: flex;
+  justify-content: flex-end;
+  width: 100%;
+
+  &.horizontal {
+    justify-content: space-between;
+    align-items: flex-end;
+  }
+
+  &.vertical {
+    flex-direction: column;
+  }
+}

src/components/intro/index.tsx

@@ -0,0 +1,27 @@
+import { h, Component } from 'preact';
+import * as style from './style.scss';
+import { bind } from '../../lib/util';
+
+interface Props {
+  onFile: (file: File) => void;
+}
+interface State {}
+
+export default class Intro extends Component<Props, State> {
+  @bind
+  onFileChange(event: Event): void {
+    const fileInput = event.target as HTMLInputElement;
+    const file = fileInput.files && fileInput.files[0];
+    if (!file) return;
+    this.props.onFile(file);
+  }
+
+  render({ }: Props, { }: State) {
+    return (
+      <div class={style.welcome}>
+        <h1>Drop, paste or select an image</h1>
+        <input type="file" onChange={this.onFileChange} />
+      </div>
+    );
+  }
+}

src/components/intro/style.scss

@@ -0,0 +1,22 @@
+.welcome {
+  margin: auto;
+  text-align: center;
+
+  h1 {
+    font-weight: inherit;
+    font-size: 150%;
+    text-align: center;
+  }
+
+  input {
+    display: inline-block;
+    width: 16em;
+    padding: 10px;
+    margin: 0 auto;
+    -webkit-appearance: none;
+    border: 1px solid var(--button-fg);
+    background: rgba(var(--button-fg-color), 0.1);
+    border-radius: 3px;
+    cursor: pointer;
+  }
+}