Question

我有ImageView。我需要对ImageView使用onLongClickListener。当我使用这段代码时，没有任何事情发生。

代码：

 gallery=(Gallery)findViewById(R.id.gall1);

 gallery.setAdapter(new ImageAdapter(MainActivity.this));

            gallery.setOnItemClickListener(new OnItemClickListener()
            {

                @Override
                public void onItemClick(
                        AdapterView<?> parent, View v,
                        int position, long id) {
                    // TODO Auto-generated method stub

                    final ImageView imageView = (ImageView) findViewById(R.id.image1);
                    imageView.setImageResource(imageIDs[position]);

                    imageView.setLongClickable(true);


     imageView.setOnLongClickListener(new View.OnLongClickListener(){

        @Override
        public boolean onLongClick(View v) {
            // TODO Auto-generated method stub

                            Toast.makeText(getApplicationContext(), "Long Press work", Toast.LENGTH_SHORT).show();

        return true;
            }

      });


  imageView.setOnTouchListener(new View.OnTouchListener() {

    @Override
    public boolean onTouch(View v,MotionEvent event) {
    // TODO Auto-generated method stub
    layoutParams = (RelativeLayout.LayoutParams) imageView.getLayoutParams();

        switch(event.getAction())
             {
   case MotionEvent.ACTION_DOWN :
      {
   parms = (RelativeLayout.LayoutParams) imageView.getLayoutParams();

            dx = event.getRawX() - parms.leftMargin;
    dy = event.getRawY() - parms.topMargin;
     }
 break;
  case MotionEvent.ACTION_MOVE :
{   
 x = event.getRawX();
 y = event.getRawY();
  parms.leftMargin = (int) (x-dx);
 parms.topMargin = (int) (y - dy);
                                    imageView.setLayoutParams(parms);
     }
 break;
 case MotionEvent.ACTION_UP :
 {

     }
   break;
 }

  return true;
    }
});
    }


 });

Answer 1

您需要按代码启用长按：

imageView.setLongClickable(true);
imageView.setClickable(true);

最后一行可能没有必要，但也没有任何麻烦。

Answer 2

没有必要在代码中执行setLongClickable，在XML中定义它时更好

 android:longClickable="true"

OnLongClickListener无法正常工作

2 个答案: