如何找出应用程序保存我的可变位图的位置

Question

我正在研究模因生成器。现在，我正在尝试从我的设备上传一张照片，通过 Canvas 在照片上添加标题，并通过在其中创建一个新文件夹将新位图保存到我设备的 "Gallery" 应用程序。这是我的尝试：

public void createBitmapAndSave(ImageView img){
        BitmapDrawable bitmapDrawable = ((BitmapDrawable) img.getDrawable());
        Bitmap bitmap = bitmapDrawable.getBitmap();
        Bitmap mutableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);

        Canvas canvas = new Canvas(mutableBitmap);
        Paint paint = new Paint();

        String topText = topTextView.getText().toString();
        String bottomText = bottomTextView.getText().toString();

        canvas.drawText(topText, 0, 0, paint);
        canvas.drawText(bottomText, 50, 50, paint);

        File file;

        String path = Environment.getExternalStorageDirectory().toString();

        file = new File(path, "Meme" + ".jpg");

        try{
            OutputStream stream = null;

            stream = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.JPEG,100,stream);
            stream.flush();
            stream.close();
        }catch (IOException e){ e.printStackTrace(); }

    }

我正在 BroadcastReceiver:

中调用方法

private BroadcastReceiver listener = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent ) {
            String data = intent.getStringExtra("DATA");
            Toast.makeText(context, data + " received", Toast.LENGTH_SHORT).show();
            createBitmapAndSave(imageView);
        }
    };

目前，我什至不确定位图的编辑或保存是否有效，因为我在我的应用程序文件夹中找不到它。

更新

我发现了问题。我决定在 try/catch 块内放置一条 toast 消息以查看流是否正常工作，因为在它位于 try/catch 块之外之前我会在每个运行处看到它。这就是我所做的：

public void createBitmapAndSave(ImageView img){
        BitmapDrawable bitmapDrawable = ((BitmapDrawable) img.getDrawable());
        Bitmap bitmap = bitmapDrawable.getBitmap();
        Bitmap mutableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);

        Canvas canvas = new Canvas(mutableBitmap);
        Paint paint = new Paint();

        String topText = topTextView.getText().toString();
        String bottomText = bottomTextView.getText().toString();

        canvas.drawText(topText, 0, 0, paint);
        canvas.drawText(bottomText, 50, 50, paint);

        File file;

        String path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM).getAbsolutePath();
        file = new File(path, "Meme" + ".jpg");

        try{
            OutputStream stream = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.JPEG,100,stream);
            stream.flush();
            stream.close();
            Toast.makeText(getContext(), path, Toast.LENGTH_SHORT).show();
        }catch (IOException e){ e.printStackTrace();}
    }

现在，我根本看不到 toast 消息。似乎流甚至无法正常工作，但我不明白为什么不能。

Answer 1

不要使用 String path = Environment.getExternalStorageDirectory().toString(); 它会将您的文件存储在用户不可见的私人存储中。

使用File path = Environment.getExternalStoragePublicDirectory( Environment.DIRECTORY_PICTURES);

如何找出应用程序保存我的可变位图的位置

How do find out where the app saved my mutable bitmap

java

android

android-canvas

android-bitmap