Question

MyGallery gallery = (MyGallery)findViewById(R.id.gallery_photo);
PhonePhotoViewerAdapter = new PhonePhotoViewerAdapter(this, FilePath);
gallery.setAdapter(PhonePhotoViewerAdapter);
gallery.setSelection(0);

以上是我用scrollview显示照片的代码但如果我想专注于下一步，我必须用更大的距离在屏幕上移动手指我想让它在更小的距离移动时改变焦点我该怎么办？我修改了类库如下：

@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
if (e1.getX() - e2.getX() > 50  && Math.abs(velocityX) > 100) {    
// Fling left 
} else if (e2.getX() - e1.getX() > 50 && Math.abs(velocityX) > 100) {    
// Fling right 
}  
return false;
}

以下代码是我的修改：

gallery.setLongClickable(false);
gallery.setOnTouchListener(new OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            // TODO Auto-generated method stub
            int action = event.getAction();
            if((action == MotionEvent.ACTION_DOWN) && !Clicking) {
                StartX = event.getX();
                StartIndex = gallery.getSelectedItemPosition();
                Clicking = true;
            }
            else if((action == MotionEvent.ACTION_UP) && Clicking) {
                EndX = event.getX();
                EndIndex = gallery.getSelectedItemPosition();
                Clicking = false;
                if(((EndX - StartX) > 50) && (StartIndex == EndIndex)) {
                    if(EndIndex > 0) {
                        gallery.setSelection(EndIndex - 1);
                    }
                }
                else if(((StartX - EndX) > 50) && (StartIndex == EndIndex)) {
                    if(EndIndex < count - 1) {
                        gallery.setSelection(EndIndex + 1);
                    }
                }               
            }
            return false;
        }
    });

但是在表现方面存在一些异常。

Answer 1

我找到了问题的解决方案这是MyGallery定义如下：

public class MyGallery extends Gallery {
    public MyGallery(Context context, AttributeSet attrSet) {
        super(context, attrSet);
    }

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
        int kEvent;    
        if(isScrollingLeft(e1, e2)) {   
            //Check if scrolling left       
            kEvent = KeyEvent.KEYCODE_DPAD_LEFT;    
        }  
        else {   
            //Otherwise scrolling right      
            kEvent = KeyEvent.KEYCODE_DPAD_RIGHT;     
        }    
        onKeyDown(kEvent, null);    
        return true;    
    }

    private boolean isScrollingLeft(MotionEvent e1, MotionEvent e2) {
        return e2.getX() > e1.getX();   
    }  

    @Override
    protected android.view.ViewGroup.LayoutParams generateLayoutParams (android.view.ViewGroup.LayoutParams p) {
        return super.generateLayoutParams(p);
    }
}

如何更改图库的滚动视图

1 个答案: