App 代表顶层应用，管理所有页面和全局数据，以及提供生命周期回调等。它也是一个构造方法，生成 App 实例。
一个应用就是一个 App 实例。
每个应用顶层一般包含三个文件。
1）app.json：应用配置；
2）app.js：应用逻辑；
3）app.acss：应用样式（可选）；
一个简单的 app.json 代码如下。
1 2 3 4 5 6 7 8 9 | <span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">{</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-string cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">"pages"</span>: [</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-string" style="color: #669900; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">"pages/index/index"</span>,</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-string" style="color: #669900; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">"pages/logs/logs"</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> ],</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-string cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">"window"</span>: {</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-string cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">"defaultTitle"</span>: <span class="cm-string" style="color: #669900; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">"Demo"</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> }</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">}</span></span> |
这段代码配置指定应用包含两个页面（index 和 logs），以及应用窗口的默认标题设置为 “Demo”。
一个简单的 app.js 代码如下。
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | <span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="cm-variable" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">App</span>({</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">onLaunch</span>(<span class="cm-def" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">options</span>) {</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-comment" style="color: #6a737d; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">// 第一次打开</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> },</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">onShow</span>(<span class="cm-def" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">options</span>) {</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-comment" style="color: #6a737d; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">// 应用启动，或从后台被重新打开</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> },</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">onHide</span>() {</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-comment" style="color: #6a737d; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">// 应用从前台进入后台</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> },</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">onError</span>(<span class="cm-def" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">msg</span>) {</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-comment" style="color: #6a737d; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">// 应用发生脚本错误或 API 调用出现报错</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-variable" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">console</span>.<span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">log</span>(<span class="cm-variable-2" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">msg</span>);</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> },</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">globalData</span>: {</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-comment" style="color: #6a737d; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">// 全局数据</span></span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> <span class="cm-property" style="color: #005cc5; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">name</span>: <span class="cm-string" style="color: #669900; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">'taobao'</span>,</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"> },</span></span><span class="lake-preview-line" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);"><span class="lake-preview-codeblock-content" style="color: #595959; margin: 0px; padding: 0px; background: none 0% 0% / auto repeat scroll padding-box border-box rgba(0, 0, 0, 0);">});</span></span> |
