Question

从昨天开始，我已经在SO中尝试了“如何在第二次活动中传递图像”和相关的所有解决方案。他们都没有帮助我，所以我需要一些帮助。我没有问题传递另一个字符串等但图像不想进入activity2。这是我的代码以及我所做的和尝试from this thread

FirstActivity

 listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

    @Override
    public void onItemClick(AdapterView<?> parent, final View view, int position, long id) {

      Intent intent = new Intent(Restaurants.this, RestaurantInformation.class);

      intent.putExtra("id", restaurantAdaptor.getItemId(position));
      intent.putExtra("text", stocks[position].text); 
      intent.putExtra("name", stocks[position].name);

      ByteArrayOutputStream bStream = new ByteArrayOutputStream();
      bitmap.compress(Bitmap.CompressFormat.PNG, 100, bStream);
      byte[] byteArray = bStream.toByteArray();

      intent.putExtra("image", byteArray);
      startActivity(intent);
      finish();
  }

 });

在收到的活动中，我有这个

String text, name;
ImageView imgView;

long rest_id;
TextView txtView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.restaurant_informations);

    txtView = (TextView) findViewById(R.id.name);
    txtView = (TextView) findViewById(R.id.text);
    imgView = (ImageView) findViewById(R.id.image1);

    Bundle b = getIntent().getExtras();
    if (b != null) {

        rest_id = b.getLong("id");
        txtView.setText(rest_id+"");

        name = b.getString("name");
        ((TextView)findViewById(R.id.name)).setText(name+"");

        text = b.getString("text");
        ((TextView)findViewById(R.id.text)).setText(text+"");


        Bitmap bmp;

        byte[] byteArray = getIntent().getByteArrayExtra("image");
        bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);

        imgView.setImageBitmap(bmp);

当我点击listview项目时，应用程序崩溃并在LogCat我得到了这个

11-18 04:16:25.746: E/AndroidRuntime(1799): FATAL EXCEPTION: main
11-18 04:16:25.746: E/AndroidRuntime(1799): Process: com.reserveme, PID: 1799
11-18 04:16:25.746: E/AndroidRuntime(1799): java.lang.NullPointerException
11-18 04:16:25.746: E/AndroidRuntime(1799):     at com.reserveme.Restaurants$1.onItemClick(Restaurants.java:101)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.widget.AdapterView.performItemClick(AdapterView.java:299)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.widget.AbsListView.performItemClick(AbsListView.java:1113)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.widget.AbsListView$PerformClick.run(AbsListView.java:2904)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.widget.AbsListView$3.run(AbsListView.java:3638)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.os.Handler.handleCallback(Handler.java:733)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.os.Handler.dispatchMessage(Handler.java:95)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.os.Looper.loop(Looper.java:136)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at android.app.ActivityThread.main(ActivityThread.java:5017)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at java.lang.reflect.Method.invokeNative(Native Method)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at java.lang.reflect.Method.invoke(Method.java:515)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
11-18 04:16:25.746: E/AndroidRuntime(1799):     at dalvik.system.NativeStart.main(Native Method)

101中的行号Restaurants是

bitmap.compress(Bitmap.CompressFormat.PNG, 100, bStream);

Answer 1

您应该将图像保存到手机中的某个位置，然后通过意图传递保存图像的URI。并在第二个活动中访问该URI。

使用此代码保存文件

String path = Environment.getExternalStorageDirectory().toString();
OutputStream fOut = null;
File file = new File(path, "filename.jpg"); // the File to save to
fOut = new FileOutputStream(file);

Bitmap pictureBitmap = getImageBitmap(myurl); // obtaining the Bitmap
pictureBitmap.compress(Bitmap.CompressFormat.JPEG, 85, fOut); // saving the Bitmap to a file compressed as a JPEG with 85% compression rate
fOut.flush();
fOut.close(); // do not forget to close the stream

MediaStore.Images.Media.insertImage(getContentResolver(),file.getAbsolutePath(),file.getName(),file.getName());

Answer 2

最佳做法是使用活动1：

try {
    //Write file
    String filename = "bitmap.png";
    FileOutputStream stream = this.openFileOutput(filename, Context.MODE_PRIVATE);
    bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);

    //Cleanup
    stream.close();
    bmp.recycle();

    //Pop intent
    Intent in1 = new Intent(this, Activity2.class);
    in1.putExtra("image", filename);
    startActivity(in1);
} catch (Exception e) {
    e.printStackTrace();
}

在活动2中，加载位图：

Bitmap bmp = null;
String filename = getIntent().getStringExtra("image");
try {
    FileInputStream is = this.openFileInput(filename);
    bmp = BitmapFactory.decodeStream(is);
    is.close();
} catch (Exception e) {
    e.printStackTrace();
}

解决您的问题

 listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

    @Override
    public void onItemClick(AdapterView<?> parent, final View view, int position, long id) {

      Intent intent = new Intent(Restaurants.this, RestaurantInformation.class);

      intent.putExtra("id", restaurantAdaptor.getItemId(position));
      intent.putExtra("text", stocks[position].text); 
      intent.putExtra("name", stocks[position].name);

        final ImageView imageView = (ImageView) view.findViewById(R.id.image);
        final BitmapDrawable bitmapDrawable = (BitmapDrawable) imageView.getDrawable();
        final Bitmap yourBitmap = bitmapDrawable.getBitmap();



      ByteArrayOutputStream bStream = new ByteArrayOutputStream();
      yourBitmap.compress(Bitmap.CompressFormat.PNG, 100, bStream);
      byte[] byteArray = bStream.toByteArray();

      intent.putExtra("image", byteArray);
      startActivity(intent);
      finish();
  }

 });

无法将图像传递给第二个活动

2 个答案: