何時在android studio中使用FileProvider…完全是初學者

Question

我試圖在android studio中獲取有關制作應用程序的知識，因此，如果發現此代碼段。

enter code herestatic final int REQUEST_TAKE_PHOTO = 1;
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// Ensure that there's a camera activity to handle the intent
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
    // Create the File where the photo should go
    File photoFile = null;
    try {
        photoFile = createImageFile();
    } catch (IOException ex) {
        // Error occurred while creating the File
        ...
    }
    // Continue only if the File was successfully created
    if (photoFile != null) {
        Uri photoURI = FileProvider.getUriForFile(this,
                                              "com.example.android.fileprovider",
                                              photoFile);
        takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
        startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
    }
}

}

我幾乎了解所有代碼，但是我只是與“ FileProvider”混淆！ 它是什么 ？ 什么時候使用呢？

Answer 1

就您的代碼而言，它用於創建（照片的）實際文件並獲取handle ...

    // Create the File where the photo should go
    File photoFile = null;
    try {
        photoFile = createImageFile();
    } catch (IOException ex) {
        // Error occurred while creating the File
        ...
    }

..然后使用句柄獲取其URI（在手機存儲中的位置）

Uri photoURI = FileProvider.getUriForFile(this,"com.example.android.fileprovider", photoFile);

...然后拍照。 保存到該位置（URI）

takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);

您提供的代碼中的注釋相當不錯