将位图图像从一个活动传递到另一个活动

Question

在我的应用程序中,我正在显示来自图库的图像,一旦我选择一个图像,图像应该被发送到新活动,其中所选图像将被设置为背景.但是,我能够获取图像从图库,但一旦我选择一个应用程序崩溃.谢谢提前

活动-1(图像显示在图库中,所选图像将发送到新活动)

public class Gallery 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.gallery);

        Button buttonLoadImage = (Button) findViewById(R.id.buttonLoadPicture);


        buttonLoadImage.setOnClickListener(new View.OnClickListener() {

            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);
            }
        });
    }



    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 contentUri = data.getData();          
            String[] proj = { MediaStore.Images.Media.DATA };         
            Cursor cursor = managedQuery(contentUri, proj, null, null, null);         
            int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);         
            cursor.moveToFirst();         
            String tmppath = cursor.getString(column_index);           
            Bitmap croppedImage = BitmapFactory.decodeFile(tmppath);


            // Bitmap croppedImage = BitmapFactory.decodeFile(croppedImage);
            Intent intent = new Intent(Gallery.this,GesturesActivity.class);
            intent.putExtra("bmp",croppedImage);
            startActivity(intent);

            Log.v("sending image","sending image");


        }


    }
}

活性-1(XML)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@drawable/background"
    >
    <ImageView
            android:id="@+id/imgView"
            android:layout_width="fill_parent"
            android:layout_weight="1" android:layout_height="wrap_content"></ImageView>
    <Button 
            android:layout_height="wrap_content" 
            android:text="Load Picture" 
            android:layout_width="wrap_content" 
            android:id="@+id/buttonLoadPicture" 
            android:layout_weight="0" 
            android:layout_gravity="center"></Button>
</LinearLayout>

活动-2(应将所选图像设置为屏幕背景图像的活动)

  public class GesturesActivity extends Activity {


        private final int MENU_CAMERA = Menu.FIRST;


        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            requestWindowFeature(Window.FEATURE_NO_TITLE);


            Bitmap bmp = (Bitmap)this.getIntent().getParcelableExtra("bmp");
            BitmapDrawable background = new BitmapDrawable(bmp);
            getWindow().setBackgroundDrawable(background);  //background image of the screen



            Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.advert);
            View view = new SandboxView(this, bitmap);

            setContentView(view);
        }



        public boolean onPrepareOptionsMenu(Menu menu) {
            menu.clear();

                menu.add(0, 11, 0, "Take Snapshot");

                    return super.onPrepareOptionsMenu(menu);
        }


        public boolean onOptionsItemSelected(MenuItem item) {

            return super.onOptionsItemSelected(item);
        }



    }

Answer 1

有3种解决方案可以解决这个问题.

1)首先将图像转换为字节数组然后传入Intent并在下一个活动中从Bundle获取字节数组并转换为图像(位图)并设置为ImageView.

将位图转换为字节数组: -

Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();

将字节数组传递给intent: -

Intent intent = new Intent(this, NextActivity.class);
intent.putExtra("picture", byteArray);
startActivity(intent);

从Bundle获取字节数组并转换为位图图像: -

Bundle extras = getIntent().getExtras();
byte[] byteArray = extras.getByteArray("picture");

Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
ImageView image = (ImageView) findViewById(R.id.imageView1);

image.setImageBitmap(bmp);

2)首先将图像保存到SD卡中,然后在下一个活动中将此图像设置为ImageView.

3)将Bitmap传递给Intent并从bundle中获取下一个活动中的位图,但问题是如果你的位图/图像大小很大,那时图像不会在下一个活动中加载.

Answer 2

由于您是从Gallery中检索图像,为什么不将id传递给下一个活动并检索该活动中的图像而不是传递图像？这将有助于您记忆和表现.

Answer 3

Bitmap实现了Parcelable,因此您可以始终在intent中传递它.尝试以下代码:

第一项活动.

Intent mIntent = new Intent(this, ActivityTwo.class);
mIntent.putExtra("bmp_img", bmp);

要获得目标活动的输出,请尝试:

第二项活动.

Bitmap mBitmap = (Bitmap) intent.getParcelableExtra("bmp_img");

你总是使用getParcelableExtra("key")来获取Activity中传递的Bitmap.