java - ViewPager 中的 onClick 图像

Question

我在 ViewPager. 的帮助下制作了一个图像 slider 我想展现不同的toast在 ViewPager 加载的不同图像中单击时出现消息，我该怎么做？

这是我的 Activity ，其中显示图像 slider :

public class MainActivity extends AppCompatActivity{
    public static final String MAIN = "OTHER";
    private static ViewPager mPager;
    private static int currentPage = 0;
    private static final Integer[] XMEN=
            {R.drawable.benz2, R.drawable.benz2,
                    R.drawable.benz2};
    private ArrayList<Integer> XMENArray = new ArrayList<Integer>();
    @Override
    protected void onCreate(...);
        init();
}
private void init() {
        for(int i=0;i<XMEN.length;i++)
            XMENArray.add(XMEN[i]);

        mPager = (ViewPager) findViewById(R.id.pager);
        mPager.setAdapter(new com.example.nepali_test.MyAdapter(MainActivity.this,XMENArray));
        CircleIndicator indicator = (CircleIndicator) findViewById(R.id.indicator);
        indicator.setViewPager(mPager);
        final Handler handler = new Handler();
        final Runnable Update = new Runnable() {
            public void run() {
                if (currentPage == XMEN.length) {
                    currentPage = 0;
                }
                mPager.setCurrentItem(currentPage++, true);
            }
        };
        Timer swipeTimer = new Timer();
        swipeTimer.schedule(new TimerTask() {
            @Override
            public void run() {
                handler.post(Update);
            }
        }, 3000, 3000);
    }

这是 viewpager 的适配器:

public class MyAdapter extends PagerAdapter {

    private ArrayList<Integer> images;
    private LayoutInflater inflater;
    private Context context;

    public MyAdapter(Context context, ArrayList<Integer> images) {
        this.context = context;
        this.images=images;
        inflater = LayoutInflater.from(context);
    }

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

    @Override
    public int getCount() {
        return images.size();
    }

    @Override
    public Object instantiateItem(ViewGroup view, int position) {
        View myImageLayout = inflater.inflate(R.layout.slide, view, false);
        ImageView myImage = (ImageView) myImageLayout
                .findViewById(R.id.image);
        myImage.setImageResource(images.get(position));
        view.addView(myImageLayout, 0);
        return myImageLayout;
    }

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

我尝试通过添加来制作

if (currentPage==1){
            Toast.makeText(this, "page 1", Toast.LENGTH_SHORT).show();
        }

在 init()但没有成功。

Answer 1

据我了解，您需要在单击 ViewPager 的每个页面中的图像时显示 toast，在这种情况下，一个简单的方法是添加 onClickListener到适配器的 instantiateItem 方法内的 ImageView 。所以你应该用这个改变/替换你的方法:

@NonNull
@Override
public Object instantiateItem(@NonNull final ViewGroup view, final int position) {
    View myImageLayout = inflater.inflate(R.layout.slide, view, false);
    ImageView myImage = (ImageView) myImageLayout
            .findViewById(R.id.image);
    myImage.setImageResource(images.get(position));
    myImage.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Toast.makeText(context.getApplicationContext(), "page "+position, Toast.LENGTH_SHORT).show();
        }
    });
    view.addView(myImageLayout, 0);
    return myImageLayout;
}