Question

如何从视图寻呼机中永久删除页面。我想在用户按下该屏幕上的按钮时删除页面。我在这方面苦苦挣扎。我阅读了pageradapter的文档并找到了destroyitem，但它对我没什么帮助。我可以在viewpager中添加图像，但删除仍然给我一个艰难的时间。请帮忙。

以下是获取图像的活动的代码，我想根据用户请求删除图像。

public class ImageDisplayActivity extends Activity {
private List<String> filePaths;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_display1);


    // Get Image Paths for the PagerAdapter
    filePaths = getIntent().getExtras().getStringArrayList("filePaths");
    int currPosition = getIntent().getExtras().getInt("position");

    ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
    viewPager.setCurrentItem(currPosition);

    ImagePagerAdapter adapter = new ImagePagerAdapter();
    viewPager.setAdapter(adapter);
}

private class ImagePagerAdapter extends PagerAdapter {
    @Override
    public int getCount() {
        return filePaths.size();
    }

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

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        Context context = ImageDisplayActivity.this;
        ImageView imageView = new ImageView(context);

        int padding = 16;
        imageView.setPadding(padding, padding, padding, padding);
        imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);

        // Get Image
        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
        bmOptions.inJustDecodeBounds = false;
        bmOptions.inSampleSize = 4;
        bmOptions.inPurgeable = true;
        Bitmap bitmap = BitmapFactory.decodeFile(filePaths.get(position), bmOptions);

        // Display Image
        imageView.setImageBitmap(bitmap);

        ((ViewPager) container).addView(imageView, 0);
        return imageView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object imageView) {
        ((ViewPager) container).removeView((ImageView) imageView);
    }
}

}

Answer 1

正如@Kuffs所说，从filePaths中删除项目，然后通知适配器基础数据已经改变：

filePaths.remove(...); // Remove whatever you want
adapter.notifyDatasetChanged(); // Tell the adapter that it's time to update views

Answer 2

我发布了答案，因为我无法发表评论。

您可以尝试从适配器中删除它。将其添加到您的destroyItem：

service.uploadRecord(file,size,new Callback<Map<String, Object>>() 
{

      @Override
            public void success(Map<String, Object> stringObjectMap, Response response) {
                Message msg=new Message();
                msg.obj=stringObjectMap;
                msg.what=MESSAGE_UPLOADING_STOP;
                handler.sendMessage(msg);
            }

            @Override
            public void failure(RetrofitError error) {
                handler.sendMessage(createErrorMsg(error.getMessage()));
                Log.e(RECORDER_TAG,"error--"+error.getMessage());
            }
        });

而且，你必须使ImagePagerAdapter成为一个全局变量。希望这有帮助！

ViewPager删除页面

2 个答案: