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我正在使用 GridView 来显示一组用户可以选择的类别。网格的每个项目都由一个 ImageView 和一个 TextView 组成，两者都从服务器检索。当一个项目被触摸时，另一个活动被启动。

我以为一切都很顺利，直到我注意到滚动屏幕时有些项目重复了。每当我在网格中向下滚动，然后返回时，它就会改变它的位置并被复制。但即使我触摸了混乱的项目，正确的值也会发送到下一个活动。

在 LogCat 中，任何对服务器的重复请求都会发生。事实上，我在滚动时得到了这个：

06-28 12:36:38.554: D/dalvikvm(358): GC_EXTERNAL_ALLOC freed 2061 objects / 156024 bytes in 51ms
06-28 12:36:42.915: D/dalvikvm(358): GC_FOR_MALLOC freed 6590 objects / 737528 bytes in 57ms
06-28 12:38:26.725: D/dalvikvm(358): GC_EXTERNAL_ALLOC freed 5426 objects / 468176 bytes in 71ms
06-28 12:38:26.875: D/dalvikvm(358): GC_EXTERNAL_ALLOC freed 409 objects / 17480 bytes in 68ms

看起来每次我滚动时，都会重绘...

更新：它只在我第一次向下滚动 GridView 时重绘。在此之后，所有的元素，包括重复的元素，都保持在原来的位置。

我的java类：

public void proccess(){
    int qtdCategorias = json.length();
    imagens = new Drawable[qtdCategorias];
    categorias = new String[qtdCategorias];
    for (int i=0; i<qtdCategorias; i++){
        JSONArray c = json.optJSONArray(i);
        String urlAmigavel = null;
        String imagemSite = null;
        String nomeCategoria = null;
        try {
            urlAmigavel = c.getString(6);
            imagemSite = c.getString(3);
            nomeCategoria = c.getString(2);
        } catch (JSONException e) {
            Log.e("CategoriasJogarActivity", e.toString());
            e.printStackTrace();
        }
        categorias[i] = nomeCategoria;
        imagens[i] = getImagem(urlAmigavel, imagemSite);
    }


    gridview = (GridView) findViewById(R.id.include3);

    ImageAdapter imageAdapter = new ImageAdapter(ctx, imagens, categorias);

    gridview.setAdapter(imageAdapter);

    gridview.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                int position, long id) {

            String name = null;
            String idt = null;
            try {
                JSONArray c = json.optJSONArray(position);
                name = c.getString(2);
                idt = c.getString(0);
            } catch (JSONException e) {
                Log.e("CategoriasJogarActivity",
                        "JSONException" + e.toString());
            }

            Intent in = new Intent(getApplicationContext(),
                    JogarActivity.class);
            in.putExtra(TAG_NAME, name);
            in.putExtra(TAG_ID, idt);
            in.putExtra(TAG_PRIMEIRAPERGUNTA, true);
            startActivity(in);

        }
    });
}


public Drawable getImagem(String urlAmigavel, String img) {
    String url = "http://www.qranio.com/pergunta/" + urlAmigavel + "/"+ img;
    InputStream is = null;
    try {
        URL urlImagem = new URL(url);
        is = (InputStream) getObjeto(urlImagem);
    } catch (MalformedURLException e1) {
        Log.e("CategoriasJogarActivity", e1.toString());
        e1.printStackTrace();
    }
    Drawable d = Drawable.createFromStream(is, "src");

    return d;
}

private Object getObjeto(URL url) {
    Object content = null;
    try {
        content = url.getContent();
    } catch (IOException e) {
        Log.e("CategoriasJogarActivity", e.toString());
        e.printStackTrace();
    }
    return content;
}

图像适配器类

public class ImageAdapter extends BaseAdapter{
private Context mContext;
private final Drawable[] mThumbIds;
private final String[] mTextIds;


public ImageAdapter(Context c, Drawable[] d, String[] s) {
    mContext = c;
    mThumbIds = d;
    mTextIds = s;
}

public int getCount() {
    return mThumbIds.length;
}

public Object getItem(int position) {
    return null;
}

public long getItemId(int position) {
    return 0;
}

//create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
    //ImageView imageView;
    View v;
    if (convertView == null) {  // if it's not recycled, initialize some attributes
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(     Context.LAYOUT_INFLATER_SERVICE );
        v = inflater.inflate(R.layout.gridview_item_layout, null);
        TextView text = (TextView)v.findViewById(R.id.grid_item_text);
        text.setText(mTextIds[position]);
        ImageView image = (ImageView)v.findViewById(R.id.grid_item_image);
        image.setImageDrawable(mThumbIds[position]);


    } else {

        v = (View) convertView;
    }


    return v;
}


}

gridview_item_layout xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview_item_layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:gravity="center_horizontal" >

<ImageView android:id="@+id/grid_item_image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:scaleType="fitCenter"
android:minHeight="100dip"
android:minWidth="100dip"
>
</ImageView>

<TextView android:id="@+id/grid_item_text"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="TextView"
android:gravity="center"
android:textColor="#F9A512"
android:textStyle="bold"
android:textSize="18dp"
>
</TextView>
</LinearLayout>

网格视图 xml

<?xml version="1.0" encoding="utf-8"?>
<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:numColumns="auto_fit"
android:verticalSpacing="10dip"
android:horizontalSpacing="10dip"
android:stretchMode="columnWidth"
android:gravity="center"
android:background="#FFFFFF"
android:padding="5dip"
/>

我看到了关于同一问题的其他问题，但没有一个回答。对正在发生的事情有任何想法吗？

4

5 回答 5

84

向下滚动时看到相同的项目是正常的，GridView因为在该方法中，您仅在is时getView设置可绘制对象（例如，对于出现在屏幕上时看到的第一个元素）。如果不是，则意味着您有一个回收的行视图，您没有设置正确的图像，您将保留之前在此回收视图上设置的图像。尝试像这样修改方法：ImageViewconvertViewnullGridViewconvertViewnullgetView

public View getView(int position, View convertView, ViewGroup parent) {
    View v;
    if (convertView == null) {  // if it's not recycled, initialize some attributes
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(     Context.LAYOUT_INFLATER_SERVICE );
        v = inflater.inflate(R.layout.gridview_item_layout, parent, false);
    } else {
        v = (View) convertView;
    }
    TextView text = (TextView)v.findViewById(R.id.grid_item_text);
    text.setText(mTextIds[position]);
    ImageView image = (ImageView)v.findViewById(R.id.grid_item_image);
    image.setImageDrawable(mThumbIds[position]);
    return v;
}

单击一个元素会显示正确的项目，因为您使用position参数来检索数据。

于 2012-06-28T13:36:46.177 回答
2

这是我的 Button + Textview 的 GirdView 代码

public View getView(final int position, View convertView, ViewGroup parent) {
        LayoutInflater mInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.grid_item, null);  
        } else {
            holder = (ViewHolder) convertView.getTag();
        }
        TextView text = (TextView)convertView.findViewById(R.id.texto_grid);
        text.setText(app_listaActiva_NOMBRES[position]);
        Button image = (Button)convertView.findViewById(R.id.miniatura_grid);
        image.setBackgroundResource(R.drawable.custom_button);
        image.setOnClickListener(new MyOnClickListener2(position,app_listaActiva_SONIDOS));
        return convertView;
    }
于 2014-03-03T16:53:15.037 回答
0

换这里再试试

   View v;
if (convertView == null) {  // if it's not recycled, initialize some attributes
    LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(     Context.LAYOUT_INFLATER_SERVICE );
    v = inflater.inflate(R.layout.gridview_item_layout, null);
    TextView text = (TextView)v.findViewById(R.id.grid_item_text);
    text.setText(mTextIds[position]);


} else {

    v = (View) convertView;
}
if(view!=null)
        {
               ImageView image = (ImageView)v.findViewById(R.id.grid_item_image);
               image.setImageDrawable(mThumbIds[position]);
               notifyDataSetChanged();  //Calling this helped to solve the problem. 
        }


return v;
}
于 2012-06-28T13:37:22.587 回答
0

使用ViewHolder静态类为我修复重复项。

也改变layout_width并没有帮助layout_height。fill_parent

我浏览了本教程 http://android-vogue.blogspot.com/2011/06/custom-gridview-in-android-with.html

于 2019-01-04T07:04:11.467 回答
0

发送和gridview或listview并在构造函数中实现这个方法实现onscroll监听器

    this.mGridView = mGridView;
    this.mGridView.setOnScrollListener(new OnScrollListener() {

        @Override
        public void onScrollStateChanged(AbsListView view, int scrollState) {
            Log.v("onScrollStateChanged", "onScrollStateChanged");
            if (scrollState == OnScrollListener.SCROLL_STATE_IDLE) {
                isScrollStop = true;

                notifyDataSetChanged();
            } else {
                isScrollStop = false;
            }
        }

        @Override
        public void onScroll(AbsListView view, int firstVisibleItem,
                int visibleItemCount, int totalItemCount) {
            Log.v("onScroll", "onScroll");
        }
    });
于 2015-10-19T14:48:50.300 回答