Android中如何用Intent直接打开指定文件夹并实现视频选取（适配Cordova）

Hey there! Let's figure out how to directly open your target folder and let users pick videos to send back to your Cordova app. Your current code has a few issues we can fix—let's break this down step by step.

Key Issues with Your Current Code #

• You're using Intent.ACTION_VIEW which is meant for viewing content, not selecting files. We need an action designed for file picking.
• The MIME type resource/folder isn't standard; we should use video/* to target video files specifically.
• Uri.fromFile(file) will throw a FileUriExposedException on Android 7.0+ (API 24+), so we need to use FileProvider to generate a safe Uri.
• There's no setup to direct the file picker straight to your target folder—we'll add that with Android's storage framework APIs.

Step 1: Configure FileProvider (Mandatory for Android 7.0+) #

First, add FileProvider to your AndroidManifest.xml to avoid the file Uri exposure error:

<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="${applicationId}.fileprovider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

Then create res/xml/file_paths.xml to define which directories FileProvider can access:

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="."/>
</paths>

Step 2: Updated Intent Code to Open Target Folder & Pick Videos #

Replace your existing Intent code with this:

// Define your target folder
File targetFolder = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/folder_name/");

// Create intent for picking video files
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.setType("video/*"); // Target all video types
intent.addCategory(Intent.CATEGORY_OPENABLE); // Ensure we can open the selected file

// Directly open the target folder (API 29+ / Android 10+)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
    Uri initialFolderUri = FileProvider.getUriForFile(
        this.cordova.getContext(),
        this.cordova.getContext().getPackageName() + ".fileprovider",
        targetFolder
    );
    intent.putExtra(Intent.EXTRA_INITIAL_URI, initialFolderUri);
} else {
    // Fallback for older Android versions
    intent.setDataAndType(Uri.fromFile(targetFolder), "video/*");
}

// Grant read permission to the file picker
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_GRANT_READ_URI_PERMISSION);

// Launch the picker and wait for result
if (this.cordova != null) {
    this.cordova.startActivityForResult(
        (CordovaPlugin) this,
        Intent.createChooser(intent, title),
        (srcType + 1) * 16 + returnType + 1
    );
}

Step 3: Handle the Selected Video in onActivityResult #

Once the user picks a video, you need to process the returned Uri and pass it to your Cordova app's JS layer:

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    
    if (resultCode == Activity.RESULT_OK && data != null) {
        Uri selectedVideoUri = data.getData();
        
        // Convert Uri to a real file path (works for most cases)
        String videoPath = getRealPathFromUri(selectedVideoUri);
        
        // Pass the path to your Cordova JS callback here
        // Example: callbackContext.success(videoPath);
    }
}

// Helper method to get real file path from Uri
private String getRealPathFromUri(Uri uri) {
    String path = "";
    ContentResolver resolver = this.cordova.getContext().getContentResolver();
    
    String[] projection = {MediaStore.Video.Media.DATA};
    Cursor cursor = resolver.query(uri, projection, null, null, null);
    
    if (cursor != null) {
        int columnIndex = cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DATA);
        cursor.moveToFirst();
        path = cursor.getString(columnIndex);
        cursor.close();
    }
    
    return path;
}

Step 4: Add Required Permissions #

Don't forget to add these permissions to your AndroidManifest.xml:

<!-- For Android < 13 -->
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<!-- For Android 13+ -->
<uses-permission android:name="android.permission.READ_MEDIA_VIDEO" />

Also, make sure your Cordova plugin requests runtime permissions (Android 6.0+ requires this). You can use Cordova's cordova-plugin-android-permissions to handle this easily.

Important Notes #

• Android Version Compatibility: The EXTRA_INITIAL_URI parameter only works on Android 10+ (API 29). On older versions, some file managers might still open the default directory instead of your target—this is a limitation of older Android storage APIs.
• File Manager Behavior: Some third-party file managers might not respect the EXTRA_INITIAL_URI setting. For maximum reliability, you might want to consider using a custom file picker library (like Material File Picker) wrapped into a Cordova plugin.
• SAF vs Direct Path: On Android 10+, direct access to external storage paths is restricted. Using ACTION_OPEN_DOCUMENT gives you a persistent Uri that you can use with ContentResolver to read the file content, even if the file moves.

内容的提问来源于stack exchange，提问作者Charlize Smith