Question

在完成了一些教程之后，我得到了将创建的位图保存到SD卡中的代码。但是，没有保存或创建任何内容。

我有一种方法可以检查是否可以写入外部存储，并且返回true（可以创建文件\文件夹）。但是，当我尝试创建某些东西时，它不会。

我还尝试了一种仅将字符串写入sd卡（简单文件）的方法，效果不佳。

我应该在Android Studio上设置任何配置以将文件保存到SD卡上吗？重要：使用模拟设备，不使用物理设备。我在SO \ Google上看到过有关写入SD卡的帖子。它们看起来都像我已经在做。

高度赞赏任何输入谢谢

android-manifest.xml：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.saveview">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

MainActivity.Java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        final ViewParaSalvar myCustomView = new ViewParaSalvar(this);
        Boolean CanWrite = isStoragePermissionGranted();


        myCustomView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener(){

            @Override
            public void onGlobalLayout() {

                Bitmap BmpFromView = loadBitmapFromView(myCustomView);
                saveImageToExternalStorage(BmpFromView);
            }
        });
        setContentView(R.layout.activity_main);
    }
    private File GetFinalFileName()
    {
        String root = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString();
        File myDir = new File(root + "/saved_images");
        //boolean created = myDir.mkdirs();
        //ExibirMensagemAlerta(Boolean.toString(created));
        myDir.mkdirs();
        Random generator = new Random();
        int n = 10000;
        n = generator.nextInt(n);
        String fname = "Image-" + n + ".jpg";
        File file = new File(myDir, fname);

        return file;
    }

    private void saveImageToExternalStorage(Bitmap finalBitmap) {
        try
        {
            File file = GetFinalFileName();
            try {
                FileOutputStream out = new FileOutputStream(file);
               finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
          //      ExibirMensagemAlerta(file.toString());
                out.flush();
                out.close();

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

    }
    public static Bitmap loadBitmapFromView(View view)
    {
        view.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
        Bitmap bitmap = Bitmap.createBitmap(view.getMeasuredWidth(), view.getMeasuredHeight(),
                Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bitmap);
        view.layout(0, 0, view.getWidth(), view.getHeight());
        Log.d("", "combineImages: width: " + view.getWidth());
        Log.d("", "combineImages: height: " + view.getHeight());
        view.draw(canvas);
        return bitmap;
    }
    public void ExibirMensagemAlerta(String msg)
    {
        Toast.makeText(this, msg, Toast.LENGTH_SHORT).show();
    }
    public  boolean isStoragePermissionGranted() {
        Boolean finalPerm;
        if (Build.VERSION.SDK_INT >= 23) {
            if (checkSelfPermission(android.Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    == PackageManager.PERMISSION_GRANTED) {
                //ExibirMensagemAlerta("Permission is granted");
                finalPerm = true;
                return true;
            } else {

              //  ExibirMensagemAlerta("Permission revoked");
                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
                finalPerm = false;
                return false;
            }
        }
        else { //permission is automatically granted on sdk<23 upon installation
            //ExibirMensagemAlerta("Permission is granted");
            finalPerm = true;
            return true;
        }

    }
}

无法将文件保存到SD卡

0 个答案: