如何通过选择在android系统中从SD卡上传图像

在我的应用程序中,我试图将图像发送到存储在SD卡中的服务器.当我单击一个按钮时,它会打开SD卡并以网格视图显示图像.从那我想上传我触摸它的图像.我知道将图像上传到服务器,但是我不知道从SD卡中选择图像,请帮助我…..

以下是我的代码.

public void library()
{
   Intent myIntent = new Intent();
   myIntent.setType("image/*");
   myIntent.setAction(Intent.ACTION_GET_CONTENT);
   startActivityForResult(Intent.createChooser(myIntent,"Select Picture"), 101);
}
public void onActivityResult(int requestCode, int resultCode, Intent myIntent)
{
    Intent data = null;
    if (requestCode == 101 && data != null) 
    {
    Uri selctedImageUri =data.getData(); 
    }
    else 
    {
        Toast toast = Toast.makeText(this, "No Image is selected.", Toast.LENGTH_LONG);
    toast.show();
    }
 }

如何进行,请帮助我…..

解决方法:

这是获取图库图像的目的：

    Intent intent = new Intent(Intent.ACTION_GET_CONTENT, null);
    intent.setType("image/*");
    intent.putExtra("return-data", true);
    startActivityForResult(intent, 1);

然后此代码将设置从“图像视图”中的“图库”中选择的图像：
 为此使用On ActivityResult：

    @Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    switch (requestCode) {
        case 1:
            if(requestCode == 1 && data != null && data.getData() != null){
                Uri _uri = data.getData();

                if (_uri != null) {
                    //User had pick an image.
                    Cursor cursor = getContentResolver().query(_uri, new String[] { android.provider.MediaStore.Images.ImageColumns.DATA }, null, null, null);
                    cursor.moveToFirst();

                    //Link to the image
                    final String imageFilePath = cursor.getString(0);
                    Log.v("imageFilePath", imageFilePath);
                    File photos= new File(imageFilePath);
                    Bitmap b = decodeFile(photos);
                    b = Bitmap.createScaledBitmap(b,150, 150, true);
                    ImageView imageView = (ImageView) findViewById(R.id.select_image);
                    imageView.setImageBitmap(b);
                    cursor.close();
                }
            }
            super.onActivityResult(requestCode, resultCode, data);
        }
    }

这种减小图像尺寸的方法;

 private Bitmap decodeFile(File f){
        try {
            //decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(new FileInputStream(f),null,o);

            //Find the correct scale value. It should be the power of 2.
            final int REQUIRED_SIZE=70;
            int width_tmp=o.outWidth, height_tmp=o.outHeight;
            int scale=1;
            while(true){
                if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
                    break;
                width_tmp/=2;
                height_tmp/=2;
                scale++;
            }

            //decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize=scale;
            return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
        } catch (FileNotFoundException e) {}
        return null;
    }

在这些方法中,如果传递包含图像的文件,它将调整图像的大小并返回BITMAP.

标签：android,image,sd-card,upload
来源： https://codeday.me/bug/20191011/1893253.html