填充一个GridView与ImageViews动态/编程使用ImageAdapter [英] Populating a GridView with ImageViews dynamically/programmatically using a ImageAdapter

问题描述

我尝试开发一个Android应用程序，它允许用户通过Flickr获取数据并显示在一个的GridView （有一些不错的3D动画）。有些冒险后，我得到它几乎是跑着，但现在我卡住了。

---

下面的问题：

我有一个UI线程LoadPhotosTask它获取图片来自Flickr，就像开源应用程序<一href="http://$c$c.google.com/p/apps-for-android/source/browse/trunk/#trunk/Photostream">photostream.该方法 onProgressUpdate（LoadedPhoto ...值）的子类，我叫了 addPhoto（）。到现在为止万物精 - 我得到了一些不错的位图和Flickr.photo数据与所有我需要的信息

。

  @覆盖
    公共无效onProgressUpdate（LoadedPhoto ...值）{

        addPhoto（值）;
    }
 

在另一方面，我有我的的GridView 。现在我想用照片填充它。它得到了 ImageAdapter 称为适配器（延伸 BaseAdapter ，看到这个的教程）。如果我使用 ImageAdapter 类中的数组我可以填充的GridView 有一些示例图像。但是，如果我想在运行时填充它，我不知道该怎么办。

我如何必须建立在getView方法中的 ImageAdapter ？我试图填补了 ImageAdapter 与我的价值观类 addPhoto ，但它不显示任何内部数组

所以首先我设置了照片的数量的数组我想在这样的网格显示（code是 ImageAdapter 类中）：

  //类变量
私人的ImageView [] mThumbIds;

    [...]

    公共无效setupArray（诠释计数）{
            this.mThumbIds =新的ImageView [统计]
        }
 

然后我把这种方法，我photolist的长度：

 最后Flickr.PhotoList列表= PARAMS [0];
        最终诠释计数= list.getCount（）;
        INT帮手= 0;
    imagead.setupArray（计数）;
 

后来我手动调用getView方法addPhoto方法中：

 私人无效addPhoto（LoadedPhoto ...值）{

    ImageView的形象=（ImageView的）mInflater.inflate（
    R.layout.grid_item_photo，NULL）;
    image.setImageBitmap（值[0] .mBitmap）;
    image.setTag（值[0] .mPhoto）;

    imagead.setmThumbIds（图像，值[0] .mPosition）;
    imagead.getView（值[0] .mPosition，空，mpicturesGrid）;

}
 

这是getView方法中ImageAdapter：

 公开查看getView（INT位置，查看convertView，ViewGroup中父）{

    如果（convertView == NULL）{//如果它不回收，初始化一些
        //属性

        ImageView的=新ImageView的（mContext）;
        imageView.setLayoutParams（新GridView.LayoutParams（EDGE_LENGTH，
        EDGE_LENGTH））;
        imageView.setScaleType（ImageView.ScaleType.CENTER_CROP）;
        imageView.setPadding（0，0，0，0）;
        imageView.setVisibility（View.VISIBLE）;

    } 其他 {

        ImageView的=（ImageView的）convertView;
    }
    imageView.setImageDrawable（mThumbIds [位置] .getDrawable（））;
    imageView.setTag（mThumbIds [位置] .getTag（））;

    返回ImageView的;

}
 

解决方案

您缺少的重要组成部分。

当您使用适配器你有一个方法叫 notifyDataSetChanged（）。 你缺少存在的逻辑如下：

在创建适配器为的GridView 留在该适配器将使用该列表的参考。是这样的：

 私人的ArrayList＆LT;图片＆GT; mPhotos;
私人BaseAdapter mAdapter;
私人的GridView mGridView;

的onCreate：

/ *这里其他的东西* /

mAdapter =新MyAdapter（mPhotos）;
mGridView.setAdapter（mAdapter）;
 

什么，你addPhoto应该做的是以下几点：

  mPhotos.add（照片）;
mAdapter.notifyDataSetChanged（）;
 

就是这样。

I try to develop an Android App which allows the user to fetch data from flickr and show it in a GridView (with some nice 3D-Animation). After some adventures i got it almost running, but now I'm stuck.

---

Here's the problem:

I got a UI Thread "LoadPhotosTask" which gets the pictures from flickr, just like the open source application photostream. In the method onProgressUpdate(LoadedPhoto... value) of that subclass I call addPhoto(). Until now everythings fine - I got some nice Bitmap and Flickr.photo data with all the information I need.

        @Override
    public void onProgressUpdate(LoadedPhoto... value) {

        addPhoto(value);
    }

On the other hand I have got a GridView. Now I want to fill it with the Photos. It has got an adapter called ImageAdapter (which extends BaseAdapter, see this tutorial). If I use an array inside the ImageAdapter class I can populate the GridView with some sample images. But if I want to populate it at runtime, I don't know what to do.

How do I have to set up the getView method in the ImageAdapter? I was trying to fill the array inside the ImageAdapter class with my values in addPhoto, but it doesn't display anything.

So first of all I was setting up the array with the amount of Photos i wanted to display in the grid like that (code is inside the ImageAdapter class):

// class variable
private ImageView[] mThumbIds;

    [...] 

    public void setupArray(int count) {
            this.mThumbIds = new ImageView[count];
        }

Then I call this method with the lenght of my photolist:

    final Flickr.PhotoList list = params[0];
        final int count = list.getCount();
        int helper = 0;
    imagead.setupArray(count);

Afterwards I call the getView method manually inside the addPhoto method:

private void addPhoto(LoadedPhoto... value) {

    ImageView image = (ImageView) mInflater.inflate(
    R.layout.grid_item_photo, null);
    image.setImageBitmap(value[0].mBitmap);
    image.setTag(value[0].mPhoto);

    imagead.setmThumbIds(image, value[0].mPosition);
    imagead.getView(value[0].mPosition, null, mpicturesGrid);

}

That is the getView method inside ImageAdapter:

    public View getView(int position, View convertView, ViewGroup parent) {

    if (convertView == null) { // if it's not recycled, initialize some
        // attributes

        imageView = new ImageView(mContext);
        imageView.setLayoutParams(new GridView.LayoutParams(EDGE_LENGTH,
        EDGE_LENGTH));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(0, 0, 0, 0);
        imageView.setVisibility(View.VISIBLE);

    } else {

        imageView = (ImageView) convertView;
    }
    imageView.setImageDrawable(mThumbIds[position].getDrawable());
    imageView.setTag(mThumbIds[position].getTag());

    return imageView;

}

解决方案

You are missing a key part.

When you use an Adapter you have a method called notifyDataSetChanged(). The logic you are missing there is the following:

When creating the Adapter for the GridView stay with a reference for the list that the adapter will use. Something like:

private ArrayList<Photo> mPhotos;
private BaseAdapter mAdapter;
private GridView mGridView;

onCreate:

/* other things here */

mAdapter = new MyAdapter(mPhotos);
mGridView.setAdapter(mAdapter);

What you addPhoto should do is the following:

mPhotos.add(photo);
mAdapter.notifyDataSetChanged();

That's it.

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