Question

我的MainActivity中有以下内容：

  public void clickImage(View view) {

    //fire intent

     Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
     File fp = getFile();
     intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(fp));
     startActivityForResult(intent, REQUEST_CHECK);

  }

 private File getFile() {
    File folder = new File("sdcard/attendence");
    if (!folder.exists()) {
        folder.mkdir();
    }
    imgpath = new File(folder, File.separator +

            Calendar.getInstance().getTime() + ".jpg");


    return imgpath;
 }

 @Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {


    try{
        s = imgpath.toString();
        Toast.makeText(this, s, Toast.LENGTH_SHORT).show();
    }
    catch (Exception e){
        e.printStackTrace();

    }
    imgv1.setImageDrawable(Drawable.createFromPath(s));


}
public void sand(View view)
{
    db=mdb.getWritableDatabase();
    ContentValues cv =new ContentValues();
    cv.put("path" ,s);
    db.insert("tableimage", null, cv);
    Toast.makeText(this, "Done", Toast.LENGTH_SHORT).show();
}
public void show (View view) {
    String col[] = {"path"};
    db = mdb.getReadableDatabase();
    c = db.query("tableimage", col, null, null, null, null, null);

    c.moveToLast();

    imgs = c.getString(c.getColumnIndex("path"));

    imgv2.setImageDrawable(Drawable.createFromPath(imgs));
 }

我在清单中包含了读写外部存储空间。当我尝试获取图像时，它会给我许可错误（请参阅标题）。请帮忙。

Answer 1

您需要在Marshmallow或以上的Android版本中添加运行时权限请求。这是代码：

全局声明文件：

File fp;

在获取文件之前添加运行时请求：

final int MyVersion = Build.VERSION.SDK_INT;

if (MyVersion > Build.VERSION_CODES.LOLLIPOP_MR1) {
       if (!checkIfAlreadyhavePermission()) {
           ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.READ_EXTERNAL_STORAGE}, 1);
       } else {
           vfp = getFile();
       }
 }

checkIfAlreadyhavePermission（）方法：

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

在onRequestPermissionResult（）中定义ALLOW和DENY动作：

@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) {
                   fp = getFile();

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

无法解码流：java.io.FileNotFoundException：sdcard / name / c.jpg：open failed：EACCES（Permission denied）

1 个答案: