我正在使用Ionic构建一个音乐播放器应用程序,那么我如何使用file cordova插件从文件存储中扫描音乐文件,以便用户可以选择要播放的歌曲。
您需要访问音乐文件并播放它们。有一些Cordova插件,应该有助于访问本地的东西。在您的项目中添加一个或多个插件后,我发现它们在github仓库中有非常有用的文档和示例。在npm页面中有一个链接。
访问文件有
- cordova-plugin-file: https://www.npmjs.com/package/cordova-plugin-file
- cordova-plugin-iospicker: https://www.npmjs.com/package/cordova-plugin-iosaudiopicker
- cordova-plugin-mediapicker: https://github.com/an-rahulpandey/cordova-plugin-mediapicker
根据您的目标设备类型,以及您希望用户访问媒体文件的位置,您可能需要使用其中一个或所有这些。
播放文件:
- cordova-plugin-media: https://www.npmjs.com/package/cordova-plugin-media
- cordova-plugin-streaming-media(如果你使用的是流音频的API): https://www.npmjs.com/package/cordova-plugin-streaming-media
- 你也可以使用HTML5媒体:https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Using_HTML5_audio_and_video
这段代码将列出所有文件夹和文件:
import { File } from "@ionic-native/file";
import { Diagnostic } from "@ionic-native/diagnostic";
constructor(
...
public file: File,
public diagnostic: Diagnostic
){
// -------------------------
listFileSys( which){
// <which> chooses the file system - see switch below
this.jcDebug += "n" + "listFileSysSKOFLO(" + which + ")";
let fileSysArray = [];
let basePath = "";
let tag = "unknown";
// ************** RECURSE *************
let jcListDir = (thisDir)=>{
tag = "jcListDir: [" + thisDir + "]";
this.file.listDir(basePath, thisDir)
.then( (data)=>{
tag = "listDir:" + thisDir;
this.jcError += "n" + tag + ":" + JSON.stringify( data);
for( let ii = 0; ii < data.length; ii += 1){
this.jcError += "n" + data[ii].name + (data[ii].isDirectory? " [D]" : " [F]");
let currentPath = thisDir;
currentPath += (currentPath.length ? "/" : "");
currentPath += data[ii].name;
this.jcError += "n" + "currentPath:" + currentPath;
fileSysArray.push( currentPath);
if( data[ii].isDirectory && ok2recurse){
jcListDir( currentPath); // RECURSE !!!
}
}
}, (errData)=>{
tag = "listDir";
this.jcError += "n" + tag + ":ERR:" + JSON.stringify( errData);
});
};
// ************** RECURSE *************
// ***********************
let runListDir = ()=>{
this.jcDebug += "n" + "basePath:" + basePath;
// !!! START listing from basePath !!!
jcListDir( ".");
}
// ***********************
switch( which)
{
case 1:
this.diagnostic.getExternalSdCardDetails()
.then( (data) => {
this.jcDebug += "n" + "sd:" + JSON.stringify( data);
this.jcDebug += "n" + "Number of cards: " + data.length;
for( let ii = 0; ii < data.length; ii += 1){
let thisElem = data[ii];
if( thisElem.type.toLowerCase() === "application" && thisElem.canWrite){
basePath = thisElem.filePath;
break;
}
}
if( !basePath){
this.jcDebug += "n" + "no SD card found";
return;
}
runListDir();
}, (errData)=>{
tag = "getExternalSdCardDetails";
this.jcError += "n" + tag + ":ERR:" + JSON.stringify( errData);
});
break;
case 2:
basePath = this.file.externalDataDirectory;
this.jcError += "n" + "externalDataDirectory:" + basePath;
runListDir();
break;
case 3:
basePath = this.file.dataDirectory;
this.jcError += "n" + "dataDirectory:";
runListDir();
break;
default:
alert( "which???:" + which);
return;
}
// wait for all to comnplete, then show
// assume 1000 ms is adequate delay per promise
let lastFileSysLen = -1
let checkCount = 30; // max 30 * 1000 ms = 30 seconds
// ************** RECURSE *************
let checkComplete = () => {
this.jcDebug += "n" + "checkComplete " + checkCount + " [" + fileSysArray.length + "]";
setTimeout( ()=>{
// fileSysArr length stable?
if( fileSysArray.length === lastFileSysLen){
checkCount = 0;
}
lastFileSysLen = fileSysArray.length;
checkCount -= 1;
if( checkCount > 0){
checkComplete(); // recurse
} else {
// STOP !!! and show FileSysArray
this.jcInfo += "n" + "show FileSysArray";
this.jcInfo += "n" + "fileSysArray.length = " + " [" + fileSysArray.length + "]";
fileSysArray.sort();
for( let elem of fileSysArray){
this.jcInfo += "n" + elem;
}
}
}, 1000);
};
// ************** RECURSE *************
checkComplete();
}