Android从图库获取图像到ImageView。

I'm trying to add a photo from galery to a ImageView but I get this error:

我试图将galery的照片添加到ImageView中，但是我得到了这个错误:

java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=Intent { dat=content://media/external/images/media/1 }} to activity {hotMetter.pack/hotMetter.pack.GetPhoto}: java.lang.NullPointerException

. lang。RuntimeException:未能将结果ResultInfo{who=null, request=1, result=-1, data=Intent {dat=content://media/external/images/media/ media/1}传递给activity {hotMetter.pack/hotMetter.pack. pack. pack. pack。GetPhoto }:java.lang.NullPointerException

This is my code:

这是我的代码:

      Intent intent = new Intent();
      intent.setType("image/*");
      intent.setAction(Intent.ACTION_GET_CONTENT);

      startActivityForResult(Intent.createChooser(intent,"Select Picture"), SELECT_PICTURE);
}
Bitmap bitmap=null;
public void onActivityResult(int requestCode, int resultCode, Intent data)
{

    if (resultCode == Activity.RESULT_OK)
    {
        if (requestCode == SELECT_PICTURE) 
        {
             Uri selectedImageUri = data.getData();           
             selectedImagePath = getPath(selectedImageUri);             
             tv.setText(selectedImagePath);
             img.setImageURI(selectedImageUri); 
         }
    }


 public String getPath(Uri uri) 
    {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(uri, projection, null, null, null);
        if (cursor == null) return null;
        int column_index =             cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        String s=cursor.getString(column_index);
        cursor.close();
        return s;
    }

I get the selectedImagePath="mnt/sdcard/DCIM/myimage" but on img.setImageURI(selectedImageUri); i get the error.

我得到selectedImagePath="mnt/sdcard/DCIM/myimage"但在img.setImageURI(selectedImageUri)上;我得到错误。

I've also used a Bitmap and tried to set the image from SetImageBitmap but i get the same error.

我还使用了位图并尝试从SetImageBitmap中设置图像，但是我得到了相同的错误。

LogCat:

LogCat:

05-06 19:41:34.191: E/AndroidRuntime(8466): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=Intent { dat=content://media/external/images/media/1 }} to activity {hotMetter.pack/hotMetter.pack.GetPhoto}: java.lang.NullPointerException
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.ActivityThread.deliverResults(ActivityThread.java:2532)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.ActivityThread.handleSendResult(ActivityThread.java:2574)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.ActivityThread.access$2000(ActivityThread.java:117)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:961)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.os.Looper.loop(Looper.java:123)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.ActivityThread.main(ActivityThread.java:3683)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at java.lang.reflect.Method.invokeNative(Native Method)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at java.lang.reflect.Method.invoke(Method.java:507)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at dalvik.system.NativeStart.main(Native Method)
05-06 19:41:34.191: E/AndroidRuntime(8466): Caused by: java.lang.NullPointerException
05-06 19:41:34.191: E/AndroidRuntime(8466):     at hotMetter.pack.GetPhoto.onActivityResult(GetPhoto.java:55)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.Activity.dispatchActivityResult(Activity.java:3908)
05-06 19:41:34.191: E/AndroidRuntime(8466):     at android.app.ActivityThread.deliverResults(ActivityThread.java:2528)

Advice please.Thanks!

建议please.Thanks !

13 个解决方案

#1

Run the app in debug mode and set a breakpoint on if (requestCode == SELECT_PICTURE) and inspect each variable as you step through to ensure it is being set as expected. If you are getting a NPE on img.setImageURI(selectedImageUri); then either img or selectedImageUri are not set.

在调试模式下运行应用程序，并在if (requestCode == SELECT_PICTURE)上设置断点，并在执行过程中检查每个变量，以确保按预期设置。如果你在img.setImageURI上获得NPE (selectedImageUri);然后img或selectedImageUri没有设置。

#2

Simple pass Intent first:

简单的通过意图:

Intent i = new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, RESULT_LOAD_IMAGE);

And you will get picture path on your onActivityResult:

你会得到onActivityResult的图像路径:

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) {
            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();
            ImageView imageView = (ImageView) findViewById(R.id.imgView);
            imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));
        }
    }

for full source code here

这里有完整的源代码

#3

Try the following:

试试以下:

import java.io.FileDescriptor;
import java.io.IOException;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.ParcelFileDescriptor;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class ImageGalleryDemoActivity extends Activity {


    private static int RESULT_LOAD_IMAGE = 1;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Button buttonLoadImage = (Button) findViewById(R.id.buttonLoadPicture);
        buttonLoadImage.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {

                Intent i = new Intent(
                        Intent.ACTION_PICK,
                        android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);

                startActivityForResult(i, RESULT_LOAD_IMAGE);
            }
        });
    }


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

        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) {
            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();

            ImageView imageView = (ImageView) findViewById(R.id.imgView);

            Bitmap bmp = null;
            try {
                bmp = getBitmapFromUri(selectedImage);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            imageView.setImageBitmap(bmp);

        }


    }



    private Bitmap getBitmapFromUri(Uri uri) throws IOException {
        ParcelFileDescriptor parcelFileDescriptor =
                getContentResolver().openFileDescriptor(uri, "r");
        FileDescriptor fileDescriptor = parcelFileDescriptor.getFileDescriptor();
        Bitmap image = BitmapFactory.decodeFileDescriptor(fileDescriptor);
        parcelFileDescriptor.close();
        return image;
    }


}

#4

@parag's code works great. But while loading some large images you may fail. You should use;

@parag代码伟大的工作。但是当加载一些大型图像时，您可能会失败。您应该使用;

imageView.setImageBitmap(getScaledBitmap(picturePath, 800, 800));

instead of;

而不是;

imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));

Here are my methods that you can use.

这是我的方法，你可以使用。

private Bitmap getScaledBitmap(String picturePath, int width, int height) {
    BitmapFactory.Options sizeOptions = new BitmapFactory.Options();
    sizeOptions.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(picturePath, sizeOptions);

    int inSampleSize = calculateInSampleSize(sizeOptions, width, height);

    sizeOptions.inJustDecodeBounds = false;
    sizeOptions.inSampleSize = inSampleSize;

    return BitmapFactory.decodeFile(picturePath, sizeOptions);
}

private int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {

        // Calculate ratios of height and width to requested height and
        // width
        final int heightRatio = Math.round((float) height / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value, this will
        // guarantee
        // a final image with both dimensions larger than or equal to the
        // requested height and width.
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }

    return inSampleSize;
}

#5

This is the easiest way to get image from gallery and crop ass well

这是最简单的方法，从画廊和农作物屁股得到图像。

step 1: StartActivity for result

步骤1:为结果启动活动

imageUser.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            Intent intent = new Intent(Intent.ACTION_PICK,
                    MediaStore.Images.Media.INTERNAL_CONTENT_URI);
            intent.setType("image/*");
            intent.putExtra("crop", "true");
            intent.putExtra("scale", true);
            intent.putExtra("outputX", 256);
            intent.putExtra("outputY", 256);
            intent.putExtra("aspectX", 1);
            intent.putExtra("aspectY", 1);
            intent.putExtra("return-data", true);
            startActivityForResult(intent, 1);

            }
    });

step 2:Handle the result

步骤2:处理结果

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode != RESULT_OK) {
        return;
    }
    if (requestCode == 1) {
        final Bundle extras = data.getExtras();
        if (extras != null) {
            //Get image
            Bitmap ProfilePic = extras.getParcelable("data");
            imageUser.setImageBitmap(ProfilePic);
            TextView t=(TextView)findViewById(R.id.textoverimage);
            t.setText("image Selected");
        }
    }


}

#6

I think the simplest way it's to use library ContentManager. This library for getting photo or video from a device gallery, cloud or camera. With asynchronous load from the cloud and fixed bugs for some problem devices.

我认为最简单的方法是使用library ContentManager。从设备图库、云或相机获取照片或视频的库。使用来自云的异步负载和一些问题设备的固定bug。

Download via Gradle: compile 'com.github.stfalcon:contentmanager:0.4.3' You can find documentation at https://github.com/stfalcon-studio/ContentManager

通过Gradle下载:编译“com.github.stfalcon:contentmanager:0.4.3”可以在https://github.com/stfalcon-studio/ContentManager上找到文档

#7

i think your ImageView img is not instantiated its equal to null to the compiler; that's why an NullPointerException is raised

我认为你的ImageView img没有实例化它等于null给编译器;这就是为什么会引发NullPointerException

did you call in your activity

你参加活动了吗

img = (ImageView) findViewById(R.id.my_imageview);

where my_imageview is the id of your ImageView widget!!

my_imageview是ImageView小部件的id !

#8

The original answer is that your path has to join prefix like Uri.parse("file://" + file.getPath);

最初的答案是，您的路径必须像Uri一样加入前缀。解析(“文件:/ /”+ file.getPath);

#9

Here is the code,which worked for me.

这是我的密码。

Button buttonLoadImage = (Button) findViewById(R.id.button4);
    buttonLoadImage.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(Intent.ACTION_PICK,
                    MediaStore.Images.Media.INTERNAL_CONTENT_URI);
            intent.setType("image/*");
            intent.putExtra("crop", "true");
            intent.putExtra("scale", true);
            intent.putExtra("outputX", 256);
            intent.putExtra("outputY", 256);
            intent.putExtra("aspectX", 1);
            intent.putExtra("aspectY", 1);
            intent.putExtra("return-data", true);
            startActivityForResult(intent, 1);}});
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode != RESULT_OK) {

        if (requestCode == RESULT_LOAD_IMAGE && data != null) {
            Uri imageUri = data.getData();
            imageView = (ImageView) findViewById(R.id.imgView);
            imageView.setImageURI(imageUri);}}}

in Manifest file add

在清单文件添加

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

#10

put below code in button click event

Intent ImageIntent = new Intent(Intent.ACTION_PICK,               
MediaStore.Images.Media.EXTERNAL_CONTENT_URI); //implicit intent
UploadImage.this.startActivityForResult(ImageIntent,99);

---

put below code in startActivityforResult event

Uri ImagePathAndName = data.getData();
imgpicture.setImageURI(ImagePathAndName);

#11

import android.content.Intent;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

    ImageView img;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        img = (ImageView)findViewById(R.id.imageView);
    }

    public void btn_gallery(View view) {

        Intent intent =new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.INTERNAL_CONTENT_URI);

        startActivityForResult(intent,100);
    }

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

        if (requestCode==100 && resultCode==RESULT_OK)
        {
            Uri uri = data.getData();
            img.setImageURI(uri);
        }
    }
}

#12

@Parag Chauhan soltution is working well, but I had problem - some file manager apps are returning in Intent object "file:///..." instead of "content://..." - which is needed to use query.

@Parag Chauhan soltution工作得很好，但是我遇到了问题——一些文件管理应用程序返回的是意图对象“file:///…”而不是“content:/…”-需要使用查询。

There is my short solution for that problem:

对于这个问题，我有一个简短的解决办法:

public String getRealPathFromURI(Context context, Uri contentUri) {
    Cursor cursor = null;
    try {

        if("content".equals(contentUri.getScheme())) {
            String[] proj = {MediaStore.Images.Media.DATA};
            cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
            int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            cursor.moveToFirst();
            return cursor.getString(column_index);
        }
        else{
            return contentUri.getPath();
        }


    } finally {
        if (cursor != null) {
            cursor.close();
        }
    }
}    

Based on @Parag solution,

基于@Parag解决方案,

partial solution here (@nobre) Android: Getting a file URI from a content URI?

部分解决方案(@nobre) Android:从内容URI获取一个文件URI?

parital solution here (@Nikolay) Get filename and path from URI from mediastore

这里的parital解决方案(@Nikolay)从mediastore获取文件名和路径

#13

parag-chauhan and devrim answers are perfect, but i change the onActivityResult without cursor, and it makes the code much more better.

paru -chauhan和devrim的答案是完美的，但是我在没有光标的情况下更改了onActivityResult，这使代码更好。

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

    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && data != null) {
        Uri selectedImage = data.getData();
        try {
           ImageView imageView = (ImageView) findViewById(R.id.imgView);
           imageView.setImageBitmap(getScaledBitmap(selectedImage,800,800));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
}

private Bitmap getScaledBitmap(Uri selectedImage, int width, int height) throws FileNotFoundException {
    BitmapFactory.Options sizeOptions = new BitmapFactory.Options();
    sizeOptions.inJustDecodeBounds = true;
    BitmapFactory.decodeStream(getContentResolver().openInputStream(selectedImage), null, sizeOptions);

    int inSampleSize = calculateInSampleSize(sizeOptions, width, height);

    sizeOptions.inJustDecodeBounds = false;
    sizeOptions.inSampleSize = inSampleSize;

    return BitmapFactory.decodeStream(getContentResolver().openInputStream(selectedImage), null, sizeOptions);
}

private int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {
        // Calculate ratios of height and width to requested one
        final int heightRatio = Math.round((float) height / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }
    return inSampleSize;
}