avm.js是 APICloud 推出的多端开发框架。使用 avm.js 一个技术栈可同时开发 Android & iOS 原生 App、小程序和 iOS 轻 App，且多端渲染效果统一；全新的 App 引擎 3.0 不依赖 webView，提供百分百的原生渲染，保障 App 性能和体验与原生 App 一致。
list-view 定义可复用内容的竖向滚动视图，可以优化内存占用和渲染性能，支持下拉刷新和上拉加载。可使用 scroll-view 的基本属性。
list-view 里面可放置 cell、list-header、list-footer、refresh 等组件，使用 cell 组件作为每项显示内容。
下面看一个 list-view 的示例：
<template>
<list-view id="listView" class="main" enable-back-to-top onscrolltolower={this.onscrolltolower}>
<cell class="cell c-lc-rl_ac c-sy-border_bottom c-lc-ptb" onclick={this.itemClick}>
<img class="img" src={item.url} alt="">
<text class="title c-filling-w c-pl">{item.title}</text>
</cell>
<list-footer class="footer">
<text>加载中...</text>
</list-footer>
</list-view></template><style src='../../css/c-layout-mini.css' scoped></style><style>.main { width: 100%; height: 100%;
}.cell { width: 100%; height: 70px;
}.img { height: 50px; width: 50px; margin-left: 10px;
}.title { height: 50px; font-size: 20px; line-height: 50px;
}.footer { justify-content: center; align-items: center;
}</style><script>export default { name: 'test', methods: {
apiready() { this.initData(false);
},
initData(loadMore) { var that = this; var skip = that.dataList ? that.dataList.length : 0; var dataList = []; for (var i = 0; i < 20; i++) {
dataList[i] = { title: '项目' + (i + skip), url: '../../image/nav_tab_2.png'
}
} var listView = document.getElementById('listView'); if (loadMore) {
that.dataList = that.dataList.concat(dataList);
listView.insert({ data: dataList
});
} else {
that.dataList = dataList;
listView.load({ data: dataList
});
}
},
onscrolltolower() { this.initData(true);
},
itemClick(e) {
api.alert({ msg: '当前项索引：' + e.currentTarget.index
});
}
}
}</script>
list-view 只支持 APP，需要用自定义 loader 或 APPloader 调试。调试教程可查看文档 APICloud Studio3 WiFi 真机同步和 WiFi 真机预览使用说明
list-view 自带内存回收功能，可以滚动加载更多。
给 list****-view******** 添加下拉刷新组件 ****refresh
根据 refresh 组件文档，把 refresh 标签添加到 list-view 标签中，如下:
<template>
<list-view id="listView" class="main" enable-back-to-top onscrolltolower={this.onscrolltolower}>
<refresh class="refresh" state={refreshState} onstatechange={this.onstatechange}>
<image class={refreshIconClass} src="../../image/refresh.png"></image>
<image class={refreshLoadingClass} src="../../image/loading_more.gif"></image>
<text class="refreshStateDesc">{refreshStateDesc}</text>
</refresh>
<cell class="cell c-lc-rl_ac c-sy-border_bottom c-lc-ptb" onclick={this.itemClick}>
<img class="img" src={item.url} alt="">
<text class="title c-filling-w c-pl">{item.title}</text>
</cell>
<list-footer class="footer">
<text>加载中...</text>
</list-footer>
</list-view></template>
把 refresh 组件的 css ，js 代码也复制到相应的 style 和 script 标签中，并在项目目录 image 标签下添加用到的两张下拉刷新图片。完整代码如下：
<template>
<list-view id="listView" class="main" enable-back-to-top onscrolltolower={this.onscrolltolower}>
<refresh class="refresh" state={refreshState} onstatechange={this.onstatechange}>
<image class={refreshIconClass} src="../../image/refresh.png"></image>
<image class={refreshLoadingClass} src="../../image/loading_more.gif"></image>
<text class="refreshStateDesc">{refreshStateDesc}</text>
</refresh>
<cell class="cell c-lc-rl_ac c-sy-border_bottom c-lc-ptb" onclick={this.itemClick}>
<img class="img" src={item.url} alt="">
<text class="title c-filling-w c-pl">{item.title}</text>
</cell>
<list-footer class="footer">
<text>加载中...</text>
</list-footer>
</list-view></template><style src='../../css/c-layout-mini.css' scoped></style><style>.main { width: 100%; height: 100%;
}.cell{ width: 100%; height: 70px;
}.img{ height: 50px; width: 50px; margin-left: 10px;
}.title { height: 50px; font-size: 20px; line-height: 50px;
} .footer { justify-content: center; align-items: center;
} .refresh { align-items: center; justify-content: center; background-color: #eee;
} .refreshStateDesc { color: #e3007f; font-size: 13px;
} .refreshIcon { position: absolute; width: 25px; height: 22px; bottom: 21px; left: 70px; transition-property: transform; transition-duration: 100ms;
} .refreshIcon-normal { transform: rotate(0); visibility: visible;
} .refreshIcon-dragging { transform: rotate(180deg); visibility: visible;
} .refreshIcon-refreshing { visibility: hidden;
} .refreshLoading { position: absolute; width: 22px; height: 22px; bottom: 21px; left: 70px; visibility: hidden;
} .refreshLoading-refreshing { visibility: visible;
}</style><script>
export default { name: 'test',
data(){ return { refreshState: 'normal'
}
}, computed: {
refreshIconClass(){ if (this.data.refreshState == 'normal') { return 'refreshIcon refreshIcon-normal';
} else if (this.data.refreshState == 'dragging') { return 'refreshIcon refreshIcon-dragging';
} else if (this.data.refreshState == 'refreshing') { return 'refreshIcon refreshIcon-refreshing';
}
},
refreshLoadingClass() { if (this.data.refreshState == 'refreshing') { return 'refreshLoading refreshLoading-refreshing';
} else { return 'refreshLoading';
}
},
refreshStateDesc() { if (this.data.refreshState == 'normal') { return '下拉可以刷新';
} else if (this.data.refreshState == 'dragging') { return '松开可以刷新';
} else if (this.data.refreshState == 'refreshing') { return '刷新中...';
}
}
}, methods:{
apiready() { this.initData(false);
},
initData(loadMore) { var that = this; var skip = that.dataList?that.dataList.length:0; var dataList = []; for (var i=0;i<20;i++) {
dataList[i] = { title: '项目' + (i + skip), url: '../../image/nav_tab_2.png'
}
} var listView = document.getElementById('listView'); if (loadMore) {
that.dataList = that.dataList.concat(dataList);
listView.insert({ data: dataList
});
} else {
that.dataList = dataList;
listView.load({ data: dataList
});
}
},
onscrolltolower() { this.initData(true);
},
itemClick(e) {
api.alert({ msg: '当前项索引：' + e.currentTarget.index
});
},
onstatechange(e) { var state = e.detail.state; if (state == 'normal') { this.data.refreshState = 'normal';
} else if (state == 'dragging') { this.data.refreshState = 'dragging';
} else if (state == 'refreshing') { this.data.refreshState = 'refreshing'; var that = this;
setTimeout(function(){
that.data.refreshState = 'normal';
}, 2000);
}
}
}
}</script>
通常可以把父元素定义为弹性盒子或称为容器，其子元素为弹性盒子的项目。flex 布局的主要功能是在主轴或交叉轴按预期排列分布项目，定义每个项目占用空间比例，并可跟随容器大小伸缩。
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