如何将位图保存到android库

时间：2016-04-14 13:33:41

标签： java android image bitmap gallery

不幸的是，我发现的解决方案并没有在Android 5.1.1上运行。 我有一个名为source的位图。我需要将它直接保存到我手机的图库中。我的清单包含<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 你能给我一个工作方法吗？

9 个答案:

答案 0 :(得分：14)

使用这个：

private void saveImage(Bitmap finalBitmap, String image_name) {

        String root = Environment.getExternalStorageDirectory().toString();
        File myDir = new File(root);
        myDir.mkdirs();
        String fname = "Image-" + image_name+ ".jpg";
        File file = new File(myDir, fname);
        if (file.exists()) file.delete();
        Log.i("LOAD", root + fname);
        try {
            FileOutputStream out = new FileOutputStream(file);
            finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
            out.flush();
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

答案 1 :(得分：7)

使用此代码，我们可以帮助您将图像存储到特定文件夹中，该文件夹是saved_images，文件夹图像会立即显示在图库中。 

private void SaveImage(Bitmap finalBitmap) {

String root = Environment.getExternalStoragePublicDirectory(
    Environment.DIRECTORY_PICTURES).toString();
File myDir = new File(root + "/saved_images");
myDir.mkdirs();
Random generator = new Random();

int n = 10000;
n = generator.nextInt(n);
String fname = "Image-"+ n +".jpg";
File file = new File (myDir, fname);
if (file.exists ()) file.delete ();
try {
    FileOutputStream out = new FileOutputStream(file);
    finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
    // sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, 
    //     Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
    out.flush();
    out.close();

} catch (Exception e) {
    e.printStackTrace();
}
// Tell the media scanner about the new file so that it is
// immediately available to the user.
MediaScannerConnection.scanFile(this, new String[]{file.toString()}, null,
    new MediaScannerConnection.OnScanCompletedListener() {
        public void onScanCompleted(String path, Uri uri) {
            Log.i("ExternalStorage", "Scanned " + path + ":");
            Log.i("ExternalStorage", "-> uri=" + uri);
        }
    });
}

答案 2 :(得分：4)

在一行中完成 MediaStore.Images.Media.insertImage(applicationContext.getContentResolver(), IMAGE ,"nameofimage" , "description");

答案 3 :(得分：4)

在API 29（Android Q）之前有几种不同的实现方法，但是它们都涉及一个或几个Q不推荐使用的API。在2019年，这是一种向后兼容和向前兼容的方法：

（由于是2019年，所以我将用Kotlin写作）

    /// @param folderName can be your app's name
    private fun saveImage(bitmap: Bitmap, context: Context, folderName: String) {
        if (android.os.Build.VERSION.SDK_INT >= 29) {
            val values = contentValues()
            values.put(MediaStore.Images.Media.RELATIVE_PATH, "Pictures/" + folderName)
            values.put(MediaStore.Images.Media.IS_PENDING, true)
            // RELATIVE_PATH and IS_PENDING are introduced in API 29.

            val uri: Uri? = context.contentResolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
            if (uri != null) {
                saveImageToStream(bitmap, context.contentResolver.openOutputStream(uri))
                values.put(MediaStore.Images.Media.IS_PENDING, false)
                context.contentResolver.update(uri, values, null, null)
            }
        } else {
            val directory = File(Environment.getExternalStorageDirectory().toString() + separator + folderName)
            // getExternalStorageDirectory is deprecated in API 29

            if (!directory.exists()) {
                directory.mkdirs()
            }
            val fileName = System.currentTimeMillis().toString() + ".png"
            val file = File(directory, fileName)
            saveImageToStream(bitmap, FileOutputStream(file))
            if (file.absolutePath != null) {
                val values = contentValues()
                values.put(MediaStore.Images.Media.DATA, file.absolutePath)
                // .DATA is deprecated in API 29
                context.contentResolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
            }
        }
    }

    private fun contentValues() : ContentValues {
        val values = ContentValues()
        values.put(MediaStore.Images.Media.MIME_TYPE, "image/png")
        values.put(MediaStore.Images.Media.DATE_ADDED, System.currentTimeMillis() / 1000);
        values.put(MediaStore.Images.Media.DATE_TAKEN, System.currentTimeMillis());
        return values
    }

    private fun saveImageToStream(bitmap: Bitmap, outputStream: OutputStream?) {
        if (outputStream != null) {
            try {
                bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream)
                outputStream.close()
            } catch (e: Exception) {
                e.printStackTrace()
            }
        }
    }

此外，在致电之前，您需要先拥有WRITE_EXTERNAL_STORAGE。

答案 4 :(得分：2)

这是Kotlin中一个完全可用的解决方案：

fun saveToGallery(context: Context, bitmap: Bitmap, albumName: String) {
    val filename = "${System.currentTimeMillis()}.png"
    val write: (OutputStream) -> Boolean = {
        bitmap.compress(Bitmap.CompressFormat.PNG, 100, it)
    }

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        val contentValues = ContentValues().apply {
            put(MediaStore.MediaColumns.DISPLAY_NAME, filename)
            put(MediaStore.MediaColumns.MIME_TYPE, "image/png")
            put(MediaStore.MediaColumns.RELATIVE_PATH, "${Environment.DIRECTORY_DCIM}/$albumName")
        }

        context.contentResolver.let {
            it.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, contentValues)?.let { uri ->
                it.openOutputStream(uri)?.let(write)
            }
        }
    } else {
        val imagesDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM).toString() + File.separator + albumName
        val file = File(imagesDir)
        if (!file.exists()) {
            file.mkdir()
        }
        val image = File(imagesDir, filename)
        write(FileOutputStream(image))
    }
}

答案 5 :(得分：2)

我想根据我在我的应用程序中使用的@Bao Lei 的回答添加 Java 代码。

    private void saveImage(Bitmap bitmap, Context context, String folderName) throws FileNotFoundException {
        if (android.os.Build.VERSION.SDK_INT >= 29) {
            ContentValues values = new ContentValues();
            values.put(MediaStore.Images.Media.RELATIVE_PATH, "Pictures/" + folderName);
            values.put(MediaStore.Images.Media.IS_PENDING, true);
            // RELATIVE_PATH and IS_PENDING are introduced in API 29.

            Uri uri = context.getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            if (uri != null) {
                saveImageToStream(bitmap, context.getContentResolver().openOutputStream(uri));
                values.put(MediaStore.Images.Media.IS_PENDING, false);
                context.getContentResolver().update(uri, values, null, null);
            }
        } else {
            dir = new File(getApplicationContext().getExternalFilesDir(Environment.DIRECTORY_PICTURES),"");
            // getExternalStorageDirectory is deprecated in API 29

            if (!dir.exists()) {
                dir.mkdirs();
            }

            java.util.Date date = new java.util.Date();
            imageFile = new File(dir.getAbsolutePath()
                    + File.separator
                    + new Timestamp(date.getTime()).toString()
                    + "Image.jpg");

            imageFile = new File(dir.getAbsolutePath()
                    + File.separator
                    + new Timestamp(date.getTime()).toString()
                    + "Image.jpg");
            saveImageToStream(bitmap, new FileOutputStream(imageFile));
            if (imageFile.getAbsolutePath() != null) {
                ContentValues values = new ContentValues();
                values.put(MediaStore.Images.Media.DATA, imageFile.getAbsolutePath());
                // .DATA is deprecated in API 29
                context.getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            }
        }
    }

    private ContentValues contentValues() {
        ContentValues values = new ContentValues();
        values.put(MediaStore.Images.Media.MIME_TYPE, "image/png");
        values.put(MediaStore.Images.Media.DATE_ADDED, System.currentTimeMillis() / 1000);
        values.put(MediaStore.Images.Media.DATE_TAKEN, System.currentTimeMillis());
        return values;
    }

    private void saveImageToStream(Bitmap bitmap, OutputStream outputStream) {
        if (outputStream != null) {
            try {
                bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream);
                outputStream.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

这个在我的应用中运行良好。

答案 6 :(得分：1)

现在我们有android10和android11，所以这是更新版本，将在所有android设备上运行。

在调用此函数之前，请确保您具有WRITE_EXTERNAL_STORAGE权限。

    private fun saveMediaToStorage(bitmap: Bitmap) {
        val filename = "${System.currentTimeMillis()}.jpg"
        var fos: OutputStream? = null
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            contentResolver?.also { resolver ->
                val contentValues = ContentValues().apply {
                    put(MediaStore.MediaColumns.DISPLAY_NAME, filename)
                    put(MediaStore.MediaColumns.MIME_TYPE, "image/jpg")
                    put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_PICTURES)
                }
                val imageUri: Uri? =
                    resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, contentValues)
                fos = imageUri?.let { resolver.openOutputStream(it) }
            }
        } else {
            val imagesDir =
                Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)
            val image = File(imagesDir, filename)
            fos = FileOutputStream(image)
        }
        fos?.use {
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, it)
            toast("Saved to Photos")
        }
    }

它是Kotlin，我认为非常简单并且可以自我解释代码。但是，如果您有问题，请在下面评论，我会解释。

参考： Android Save Bitmap to Gallery Tutorial 。

答案 7 :(得分：1)

从Android Q开始，将图像保存到画廊方面有所变化。感谢@BaoLei，这是我在Java中的答案，如果有人需要的话。

    private void saveImage(Bitmap bitmap) {
        if (android.os.Build.VERSION.SDK_INT >= 29) {
            ContentValues values = contentValues();
            values.put(MediaStore.Images.Media.RELATIVE_PATH, "Pictures/" + getString(R.string.app_name));
            values.put(MediaStore.Images.Media.IS_PENDING, true);

            Uri uri = this.getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            if (uri != null) {
                try {
                    saveImageToStream(bitmap, this.getContentResolver().openOutputStream(uri));
                    values.put(MediaStore.Images.Media.IS_PENDING, false);
                    this.getContentResolver().update(uri, values, null, null);
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                }

            }
        } else {
            File directory = new File(Environment.getExternalStorageDirectory().toString() + '/' + getString(R.string.app_name));

            if (!directory.exists()) {
                directory.mkdirs();
            }
            String fileName = System.currentTimeMillis() + ".png";
            File file = new File(directory, fileName);
            try {
                saveImageToStream(bitmap, new FileOutputStream(file));
                ContentValues values = new ContentValues();
                values.put(MediaStore.Images.Media.DATA, file.getAbsolutePath());
                this.getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }

        }
    }

    private ContentValues contentValues() {
        ContentValues values = new ContentValues();
        values.put(MediaStore.Images.Media.MIME_TYPE, "image/png");
        values.put(MediaStore.Images.Media.DATE_ADDED, System.currentTimeMillis() / 1000);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            values.put(MediaStore.Images.Media.DATE_TAKEN, System.currentTimeMillis());
        }
        return values;
    }

    private void saveImageToStream(Bitmap bitmap, OutputStream outputStream) {
        if (outputStream != null) {
            try {
                bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream);
                outputStream.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

答案 8 :(得分：0)

对于媒体扫描，您只需完成

x = 3
np.logical_and(x<A, A<7)
相关问题
最新问题