Question

在我的应用中，我需要一个图像滑块，我已经使用View pager做到了，但是我希望图像每2秒自动更改一次。我无法做到这一点。

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_about, container,false);
    viewPager = (ViewPager) rootView.findViewById(R.id.viewPager);
    adapter = new CustomSwipeAdapter(this.getActivity());
    viewPager.setAdapter(adapter);
    indicator = (CircleIndicator) rootView.findViewById(R.id.indicator);
    indicator.setViewPager(viewPager);
    return rootView;
}

这是我的片段类。

public class CustomSwipeAdapter extends PagerAdapter {
private int[] image_resource = {R.drawable.sample_1, R.drawable.sample_2};
private Context ctx;
private LayoutInflater layoutInflater;

public CustomSwipeAdapter(Context ctx) {
    this.ctx = ctx;
}

@Override
public int getCount() {
    return image_resource.length;
}

@Override
public boolean isViewFromObject(@NonNull View view, @NonNull Object object) {
    return (view == object);
}

@Override
public Object instantiateItem(ViewGroup container, int position) {
    layoutInflater = (LayoutInflater) ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View item_view = layoutInflater.inflate(R.layout.image_swipe_layout, container, false);
    ImageView imageview = (ImageView) item_view.findViewById(R.id.image_view);
    imageview.setImageResource(image_resource[position]);
    container.addView(item_view);
    return item_view;
}

@Override
public void destroyItem(ViewGroup container, int position, Object object) {
    container.removeView((LinearLayout)object);
}
}

这是我的适配器类。我希望该图像自动更改。请帮帮我。

Answer 1

我很久以前编写的代码，它执行类似的操作，也许可以为您提供帮助。

    final Handler handler = new Handler();
    final Runnable update = () -> {
        if (currentPage == list.size()) {
            currentPage = 0;
        }
        pager.setCurrentItem(currentPage++, true);
    };

    Timer timer = new Timer();
    timer.schedule(new TimerTask() {
        @Override
        public void run() {
            handler.post(update);
        }
    }, 2500, 2500);


   @Override
   protected void onDestroy() {
       super.onDestroy();

       timer.cancel();

   }

因此，您设置了一个计时器，该计时器在一定的时间间隔（此处为〜2.5秒）后被调用，当计时器启动时，您将检查适配器的当前页面是否到达末尾，然后将其重置为0，否则将其递增

无法在Android Fragment中自动设置图片幻灯片

1 个答案: