mimeType写了ofd类型之后，但是Preview不能正确预览ofd文件。
let fileInfo: filePreview.PreviewInfo = {
title: 'test.ofd',
uri: this.filePath,
mimeType: 'text/plain/ofd' // 预览文件类型
};
filePreview.openPreview(context, fileInfo, displayInfo) 首先要检查文件是否支持预览，预览参数配置是否正确。
filePreview.canPreview(this.uiContext, this.fileInfo.uri).then((result) => {
console.info(`Succeeded in obtaining the result of whether it can be previewed. result = ${result}`);
if (result) {
filePreview.openPreview(this.uiContext, this.fileInfo).then(() => {
console.info('openPreview success');
}).catch((err: BusinessError) => {
console.error(`openPreview failed, error message: ${err.message}`);
});
} else {
console.error('File cannot be previewed');
}
}).catch((err: BusinessError) => {
console.error(`Failed to obtain the result of whether it can be previewed, err.code = ${err.code}, err.message = ${err.message}`);
}); Preview Kit支持的文件类型只有文件后缀类型与mimeType类型相匹配时，才能正常预览文件。ofd文件的mimeType类型为general.ofd，也可以传入空值由Preview Kit判断文件类型。
// 文件预览信息
private fileInfo: filePreview.PreviewInfo = {
title: 'test.ofd', // 文件的标题名称
uri: 'file://com.example.myapplication/data/storage/el2/base/haps/entry/files/test.ofd', // 文件的uri，此处com.example.myapplication为包名，请按照应用的实际包名替换
mimeType: 'general.ofd' // 文件（夹）的类型，ofd文件的类型为general.ofd，也可以传入空值由Preview Kit判断文件类型
}; import common from '@ohos.app.ability.common';
import fs from '@ohos.file.fs';
import { filePreview } from '@kit.PreviewKit';
import { BusinessError } from '@kit.BasicServicesKit';
@Entry
@Component
struct OfdPreviewDemo {
context: common.UIAbilityContext = this.getUIContext().getHostContext() as common.UIAbilityContext;
uiContext: Context = this.getUIContext().getHostContext() as common.Context;
// 文件预览信息
private fileInfo: filePreview.PreviewInfo = {
title: 'test.ofd', // 文件的标题名称
uri: 'file://com.example.myapplication/data/storage/el2/base/haps/entry/files/test.ofd', // 文件的uri，此处com.example.myapplication为包名，请按照应用的实际包名替换
mimeType: 'general.ofd' // 文件（夹）的类型，ofd文件的类型为general.ofd，也可以传入空值由Preview Kit判断文件类型
};
copyFile() {
let file: fs.File | undefined = undefined;
try {
// 获取resources/rawfile目录下rawfile文件所在HAP的文件描述符（fd）
let srcFileDescriptor = this.context.resourceManager.getRawFdSync('test.ofd'); // 需要在rawfile目录下手动添加名为test.ofd的文件
// 判断文件是否是普通文件。true：是普通文件；false：不是普通文件。
if (!fs.statSync(srcFileDescriptor.fd).isFile()) {
console.error('Not a regular file');
return;
}
let pathDir = this.context.filesDir; // 通过UIAbilityContext获取沙箱地址filesDir
let filePath = pathDir + '/test.ofd';
// 以同步方法打开文件或目录。若文件不存在，则创建文件/读写打开
file = fs.openSync(filePath, fs.OpenMode.CREATE | fs.OpenMode.READ_WRITE) as fs.File;
let bufsize = 4096;
let buf = new ArrayBuffer(bufsize); // 用于保存读取到的文件数据的缓冲区。
let off = 0, len = 0, readLen = 0; // 动态调整目标文件的写入位置. 写入实际读取的字节数,累计已读取的总字节数
len = fs.readSync(srcFileDescriptor.fd, buf, { offset: srcFileDescriptor.offset + off, length: bufsize });
while (len) {
readLen += len;
fs.writeSync(file.fd, buf, { offset: off, length: len });
off = off + len;
// 当剩余未读取的字节数小于当前分块大小时，调整bufsize为剩余大小，避免无效读取
if ((srcFileDescriptor.length - readLen) < bufsize) {
bufsize = srcFileDescriptor.length - readLen;
}
len = fs.readSync(srcFileDescriptor.fd, buf, { offset: srcFileDescriptor.offset + off, length: bufsize });
}
} catch (error) {
console.error('openPreview failed, err = ' + error.message);
} finally {
// 关闭文件或目录
if (file) {
fs.closeSync(file);
}
this.context.resourceManager.closeRawFdSync('test.ofd');
}
}
build() {
Row() {
Column() {
Button('传到沙箱')
.onClick(() => {
this.copyFile();
})
.margin({ bottom: 10 });
Button('预览文件')
.onClick(() => {
filePreview.canPreview(this.uiContext, this.fileInfo.uri).then((result) => {
console.info(`Succeeded in obtaining the result of whether it can be previewed. result = ${result}`);
if (result) {
filePreview.openPreview(this.uiContext, this.fileInfo).then(() => {
console.info('openPreview success');
}).catch((err: BusinessError) => {
console.error(`openPreview failed, error message: ${err.message}`);
});
} else {
console.error('File cannot be previewed');
}
}).catch((err: BusinessError) => {
console.error(`Failed to obtain the result of whether it can be previewed, err.code = ${err.code}, err.message = ${err.message}`);
});
})
}
.width('100%');
}
.height('100%');
}
}