我有一个带有 2 个选项卡片段的 (Sherlock)FragmentActivity。左边的 Fragment 是一个显示相册图片的 GridView，右边的 Fragment 由一个 ViewPager 组成，用于查看单个图片。从左侧片段中，您可以滚动浏览图片并选择一张。切换（或滑动）到右侧片段将显示图片，因为它是 ViewPager，您可以滑动到上一张或下一张图片。
这很好用，只是 FragmentActivity 想要拦截右滑动并移回左侧选项卡。当我在右侧选项卡上时，我想防止 FragmentActivity 拦截滑动。如果我必须完全禁用标签之间的滑动，那将是令人满意的。我只希望滑动专用于当前选项卡，而不是用于在选项卡之间移动。
以下图像指示当前行为。右图显示了当我向右滑动时会发生什么。如您所见，左侧选项卡开始出现。我希望滑动只适用于右侧选项卡，以便我可以在图像之间滑动而不出现左侧选项卡。
我看到了在 ViewPager 中控制滑动的解决方案，但还没有找到控制选项卡式片段之间滑动的解决方案。
这是 GridView 片段和 ViewPager 片段的 xml：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<FrameLayout android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:columnWidth="100dip"
android:gravity="center"
android:horizontalSpacing="4dip"
android:numColumns="auto_fit"
android:stretchMode="columnWidth"
android:verticalSpacing="4dip" />
</FrameLayout>
</LinearLayout>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/pager"
android:layout_width="fill_parent"
android:layout_height="0px"
android:layout_weight="1"/>
</LinearLayout>
这里是 ViewPager 片段的代码摘要：
public class FragmentFlash extends SherlockFragment {
private GestureDetector gestureDetector;
View.OnTouchListener gestureListener;
private ViewPager pager = null;
private int pagerPosition;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
pagerPosition = 0;
// Gesture detection
gestureDetector = new GestureDetector(new MyGestureDetector());
gestureListener = new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
};
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.flash, container, false);
pager = (ViewPager) v.findViewById(R.id.pager);
pager.setOnTouchListener(gestureListener);
return v;
}
class MyGestureDetector extends SimpleOnGestureListener {
private static final int SWIPE_MIN_DISTANCE = 10;
private static final int SWIPE_MAX_OFF_PATH = 250;
private static final int SWIPE_THRESHOLD_VELOCITY = 50;
@Override
public boolean onDown(MotionEvent e) {
return true;//false; make onFling work with fragments
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
try {
if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH)
return false;
else
// right to left swipe
if(distanceX > SWIPE_MIN_DISTANCE) {
if (pagerPosition < imageUrls.length-1)
pager.setCurrentItem(++pagerPosition);
// left to right swipe
} else if (distanceX < -SWIPE_MIN_DISTANCE) {
if (pagerPosition > 0)
pager.setCurrentItem(--pagerPosition);
}
return true;
} catch (Exception e) {
// nothing
}
return false;
}
}
private class ImagePagerAdapter extends PagerAdapter {
private String[] images;
private LayoutInflater inflater;
ImagePagerAdapter(String[] images) {
this.images = images;
inflater = mContext.getLayoutInflater();
}
@Override
public void destroyItem(View container, int position, Object object) {
((ViewPager) container).removeView((View) object);
}
@Override
public void finishUpdate(View container) {
}
@Override
public int getCount() {
return images.length;
}
@Override
public Object instantiateItem(View view, int position) {
final View imageLayout = inflater.inflate(R.layout.item_pager_image, null);
final ImageView imageView = (ImageView) imageLayout.findViewById(R.id.image);
final ProgressBar spinner = (ProgressBar) imageLayout.findViewById(R.id.loading);
byte[] image = ;//get byte array from file at images[position];
if (null != image) {
Bitmap bitmap = BitmapFactory.decodeByteArray(image, 0, image.length);
imageView.setImageBitmap(bitmap);
}
((ViewPager) view).addView(imageLayout, 0);
return imageLayout;
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view.equals(object);
}
@Override
public void restoreState(Parcelable state, ClassLoader loader) {
}
@Override
public Parcelable saveState() {
return null;
}
@Override
public void startUpdate(View container) {
}
}
public void pagerPositionSet(int pagerPosition, String[] imageUrls) {
Log.i(Flashum.LOG_TAG, "FragmentFlash pagerPositionSet: " + pagerPosition);
if (pagerPosition >= 0)
this.pagerPosition = pagerPosition;
if (pager != null) {
pager.setAdapter(new ImagePagerAdapter(imageUrls));
pager.setCurrentItem(this.pagerPosition);
}
}
}
这是 item_pager_image.xml：
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="1dip" >
<ImageView
android:id="@+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:adjustViewBounds="true"
android:contentDescription="@string/descr_image" />
<ProgressBar
android:id="@+id/loading"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:visibility="gone" />
</FrameLayout>