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Android简单的文件选择器
发布时间:2024-01-24 01:05
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欧亿体育

可能有不足,但是却可以实现效果。

一、效果图




主要实现可以在手机本地存储中选择文件,获取文件的本地存储路径字符串。

二、AndriodStudio文件及代码

代码文件又有三个-画红圈的部分

1、MainActivity

public class MainActivity extends AppCompatActivity {

TextView filePathtextView;
Button button;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    filePathtextView = findViewById(R.id.fileTextView);

    button = findViewById(R.id.button);

    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(Intent.ACTION_GET_CONTENT);

            intent.setType("*/*");

            intent.addCategory(Intent.CATEGORY_OPENABLE);

            startActivityForResult(Intent.createChooser(intent,"需要选择文件"),1);
        }
    });








}

@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();

            String pathString = UriUtil.getPath(this,uri);

            filePathtextView.setText(pathString);



                /*
                 //保存读取到的内容
            StringBuilder result = new StringBuilder();

                //获取输入流
                InputStream is = this.getContentResolver().openInputStream(uri);
                //创建用于字符输入流中读取文本的bufferReader对象
                BufferedReader br = new BufferedReader(new InputStreamReader(is));



                String line;
                while ((line = br.readLine()) != null) {
                    //将读取到的内容放入结果字符串
                    result.append(line);
                }
                //文件中的内容
                String content = result.toString();


                 */




            }

            }

}

2、通过Uri来获取文件路径,需要Uri转换FilePath类

class UriUtil {

    /**
     * 从Uri获取文件路径,存储路径需要获取
     * android.permission.READ_EXTERNAL_STORAGE权限
     * 适用于MediaStore和其他基于文件的内容提供
     *
     * @param context 上下文对象
     * @param uri     Uri
     */

    @RequiresApi(api = Build.VERSION_CODES.KITKAT)
    public static String getPath(Context context, 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())) {
            return uri.getPath();
        }

        return null;
    }

    /**
     * Get the value of the data column for this Uri. This is useful for
     * MediaStore Uris, and other file-based ContentProviders.
     *
     * @param context       The context.
     * @param uri           The Uri to query.
     * @param selection     (Optional) Filter used in the query.
     * @param selectionArgs (Optional) Selection arguments used in the query.
     * @return The value of the _data column, which is typically a file path.
     */

    public 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.
     */

    public 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.
     */


    public 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.
     */



    public static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

}

3、activity_main.xml



三、权限设置-由于访问本地存储,所以需要申请权限

添加三句代码-位置按照图片增加


android:requestLegacyExternalStorage =“true”