BitmapFactory：无法解码流：java.io.FileNotFoundException

Question

我有关于 BitMapFactory.decodeFile 的问题。

在我的应用中，我希望用户能够从 his/her 设备 select 图片或拍照。然后必须将其显示在 ImageView

中

这是代码片段：

Uri selectedImage = data.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
                    cursor.moveToFirst();
                    int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
                    String picturePath = cursor.getString(columnIndex);
                    cursor.close();
                    MyImage image = new MyImage();
                    image.setTitle("Test");
                    image.setDescription("test choose a photo from gallery and add it to " + "list view");
                    image.setDatetime(System.currentTimeMillis());
                    image.setPath(picturePath);

我遇到了这个异常：

BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /storage/emulated/0/WhatsApp/Media/WhatsApp Images/IMG-20170302-WA0012.jpg: open failed: EACCES (Permission denied)

如何解决it.Please求助me.Thanks提前..

Answer 1

它的权限问题，你需要在manifest中添加外部读取存储的权限，然后才能使用它，如果你使用os 6.0以上，那么你需要使用Easy权限。

写入：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

待读：

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

6.0 以上：

private String[] galleryPermissions = {Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE};

if (EasyPermissions.hasPermissions(this, galleryPermissions)) {
            pickImageFromGallery();
        } else {
            EasyPermissions.requestPermissions(this, "Access for storage",
                    101, galleryPermissions);
        }

Answer 2

当您启动 CAMERA intent 时，您已请求运行次读取外部存储的权限：

final int MyVersion = Build.VERSION.SDK_INT;
        if (MyVersion > Build.VERSION_CODES.LOLLIPOP_MR1) {
            if (!checkIfAlreadyhavePermission()) {
                ActivityCompat.requestPermissions(new String[]{android.Manifest.permission.READ_EXTERNAL_STORAGE}, 1);
            } else {
               startYourCameraIntent();
            }
        }

checkIfAlreadyhavePermission() 方法：

private boolean checkIfAlreadyhavePermission() {
        int result = ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.WRITE_EXTERNAL_STORAGE);
        return result == PackageManager.PERMISSION_GRANTED;
    }

在 onRequestPermission() 中处理权限对话框 "Allow" 和 "Deny" 按钮操作：

@Override
        public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode) {
            case 1: {
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                   startYourCameraIntent();

                } else {
                    Toast.makeText(getActivity(), "Please give your permission.", Toast.LENGTH_LONG).show();
                }
                break;
            }
        }
    }

并将此添加到您的清单的应用程序标签中：

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

Answer 3

将此添加到您的 MainActivity.java 文件中

6.0 以上OS:

    if(ActivityCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.READ_EXTERNAL_STORAGE)!=PackageManager.PERMISSION_GRANTED){
        ActivityCompat.requestPermissions(MainActivity.this,new String[]{
                Manifest.permission.READ_EXTERNAL_STORAGE
        },1);

    }

 @Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if(requestCode==1){
        if(grantResults[0]==PackageManager.PERMISSION_GRANTED){

        }
        else{
            Toast.makeText(getApplicationContext(), "Permission Denied", Toast.LENGTH_LONG).show();
        }
    }
}

BitmapFactory：无法解码流：java.io.FileNotFoundException

BitmapFactory: Unable to decode stream: java.io.FileNotFoundException

android

filenotfoundexception

bitmapfactory