职场小白迷上优美句子:
推迟，拖延真的是件可怕的事，过去了好久还是原来的样子。
公司现在的项目中有一个需求，需要把本地 json 格式的数据导入到项目中使用，其实简单的逻辑就是：使用安卓隐式跳转的方式进入到文件管理器，然后寻找需要的文件，点击文件之后返回该文件的路径，之后根据路径获取到该文件并对其进行相应的操作。
这些代码不是自己在Android 官网上找的，也是从百度搜的，当然需要标明出处：
Android调用系统自带的文件管理器，打开指定路径_android file 内置文件到机器特定路径_沧海龙腾LV的博客-CSDN博客
1.进入文件管理器
private void intoFileManager() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");//无类型限制
// 有类型限制是这样的:
// intent.setType(“image/*”);//选择图片
// intent.setType(“audio/*”); //选择音频
// intent.setType(“video/*”); //选择视频 （mp4 3gp 是android支持的视频格式）
// intent.setType(“video/*;image/*”);//同时选择视频和图片
intent.addCategory(Intent.CATEGORY_OPENABLE);
startActivityForResult(intent, 1);
}
2.返回结果
String path;
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK) {
Uri uri = data.getData();
if ("file".equalsIgnoreCase(uri.getScheme())){//使用第三方应用打开
path = uri.getPath();
mFilePathTv.setText(path);
Log.d("queryfilepath", "返回结果1: " + path);
return;
}
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {//4.4以后
path = FileChooseUtil.getPath(this, uri);
mFilePathTv.setText(path);
Log.d("queryfilepath", "返回结果2: " + path);
} else {//4.4以下下系统调用方法
path = FileChooseUtil.getRealPathFromURI(uri);
mFilePathTv.setText(path);
Log.d("queryfilepath", "返回结果3: " + path);
}
}
}
3.用到的工具类
public class FileChooseUtil {
private static Context context;
private static FileChooseUtil util = null;
private FileChooseUtil(Context context) {
this.context = context;
}
public static FileChooseUtil getInstance(Context context) {
if (util == null) {
util = new FileChooseUtil(context);
}
return util;
}
/**
* 对外接口 获取uri对应的路径
*
* @param uri
* @return
*/
public String getChooseFileResultPath(Uri uri) {
String chooseFilePath = null;
if ("file".equalsIgnoreCase(uri.getScheme())) {//使用第三方应用打开
chooseFilePath = uri.getPath();
Toast.makeText(context, chooseFilePath, Toast.LENGTH_SHORT).show();
return chooseFilePath;
}
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {//4.4以后
chooseFilePath = getPath(context, uri);
} else {//4.4以下下系统调用方法
chooseFilePath = getRealPathFromURI(uri);
}
return chooseFilePath;
}
public static String getRealPathFromURI(Uri contentUri) {
String res = null;
String[] proj = {MediaStore.Images.Media.DATA};
Cursor cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
if (null != cursor && cursor.moveToFirst()) {
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
res = cursor.getString(column_index);
cursor.close();
}
return res;
}
/**
* 专为Android4.4设计的从Uri获取文件绝对路径，以前的方法已不好使
*/
@SuppressLint("NewApi")
public static String getPath(final Context context, final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
if ("primary".equalsIgnoreCase(type)) {
return Environment.getExternalStorageDirectory() + "/" + split[1];
}
}
// DownloadsProvider
else if (isDownloadsDocument(uri)) {
final String id = DocumentsContract.getDocumentId(uri);
final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
return getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
} else if ("video".equals(type)) {
contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
} else if ("audio".equals(type)) {
contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
}
final String selection = "_id=?";
final String[] selectionArgs = new String[]{split[1]};
return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
uri.getPath();
}
return null;
}
private static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
Cursor cursor = null;
final String column = "_data";
final String[] projection = {column};
try {
cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
null);
if (cursor != null && cursor.moveToFirst()) {
final int column_index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(column_index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
private static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
private static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
private static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
}
注意：记得开启手机的读写权限，不然会报权限拒绝异常：SecurityException ！ ! !