Question

我对gridview有一点问题，iamges显示正常，但当我向下滚动然后我向上滚动图像位置更改或重复我不知道为什么我有点困惑，我使用超过50到100图像但现在只有19图像我正在测试它将如何，所以我遇到了这个问题，它不会坚持它的立场。谢谢。

public class ImageAdapter extends BaseAdapter {
private Context context;


public Integer[] images = {
        R.drawable.f_alicate,R.drawable.f_arcoajustable,
        R.drawable.f_bateria,R.drawable.f_bisagra,
        R.drawable.f_bisagra2,R.drawable.f_cadena_galvanizada,
        R.drawable.f_canilla_bronze ,R.drawable.f_canilla_con_palanca,
        R.drawable.f_casco_rojo,R.drawable.f_casco_rojo2,
        R.drawable.f_cerraduracajon,R.drawable.f_cerradura_para_cajon2,
        R.drawable.f_conexion_cromado,R.drawable.f_cotra_candena,
        R.drawable.f_cuchara_albanil,R.drawable.f_cutter,
        R.drawable.f_cutter2,R.drawable.f_disco,
        R.drawable.f_corta_hiero};

// Constructor
public ImageAdapter(Context c){
    context = c;
}

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

public Object getItem(int position) {
    return images[position];
}

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

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

    ImageView imageView = null ;

        if (convertView == null) {
            imageView = new ImageView(context);
            new BitmapWorkerTask(imageView).execute(images[position]);

            //create new ImageView if it is not present and populate it with some image
        } else {
            imageView = (ImageView) convertView;
            //re-use ImageView that already exists in memory
        }
    return imageView;
}


class BitmapWorkerTask extends AsyncTask<Integer, Void, Bitmap> {
    private final WeakReference<ImageView> imageViewReference;
    private int data = 0;

    public BitmapWorkerTask(ImageView imageView) {
        // Use a WeakReference to ensure the ImageView can be garbage collected
        imageViewReference = new WeakReference<ImageView>(imageView);
    }

    // Decode image in background.
    @Override
    protected Bitmap doInBackground(Integer... params) {
        data = params[0];
        return decodeSampledBitmapFromResource(ImageAdapter.this.context.getResources(), data, 450, 450);
    }

    // Once complete, see if ImageView is still around and set bitmap.
    @Override
    protected void onPostExecute(Bitmap bitmap) {
        if (imageViewReference != null && bitmap != null) {
            final ImageView imageView = imageViewReference.get();
            if (imageView != null) {
                imageView.setImageBitmap(bitmap);
                imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
                imageView.setLayoutParams(new GridView.LayoutParams(450, 450));
            }
        }
    }
}

public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
                                                     int reqWidth, int reqHeight) {

    // First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(res, resId, options);

    // Calculate inSampleSize
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeResource(res, resId, options);
}

public static int calculateInSampleSize(
        BitmapFactory.Options options, int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if (height > reqHeight || width > reqWidth) {

        // Calculate ratios of height and width to requested height and width
        final int heightRatio = Math.round((float) height / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value, this will guarantee
        // a final image with both dimensions larger than or equal to the
        // requested height and width.
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }

    return inSampleSize;
}

}

Answer 1

在getView（）中，当重用已存在的ImageView时，您仍需要设置该视图的图像。实际上，您只需将图像设置为新的ImageView。

Answer 2

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;
}

Answer 3

试试这个 主要片段

public class Fragment_Main_Dashboard extends Fragment {
GridView dashbord_icon;


List<ItemObj_for_Dashbord_list> dashbord_list1 = getAllItemObject();

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    View view = inflater.inflate(R.layout.fragment_dashbord_alert_list, container, false);
    setHasOptionsMenu(true);
    getActivity().setTitle("Dashboard");

    Intent intent = new Intent(getActivity(), Service_for_login_check.class);
    getActivity().startService(intent);

    dashbord_icon = (GridView) view.findViewById(R.id.dashboard_icon);


    Custom_Adapter_Dashboard_grid adapter1 = new Custom_Adapter_Dashboard_grid(getActivity(), dashbord_list1);
    dashbord_icon.setAdapter(adapter1);


    dashbord_icon.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Object o = dashbord_icon.getItemAtPosition(position);


            if (position == 0) {
                Fragment fragment = new Fragment_Main_Advance_tracking();
                FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                fragmentTransaction.replace(R.id.texeting_fram, fragment);
                fragmentTransaction.addToBackStack(null);
                fragmentTransaction.commit();
            } else if (position == 1) {
                Fragment fragment = new Fragment_Main_Vehicle_Status();
                FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                fragmentTransaction.replace(R.id.texeting_fram, fragment);
                fragmentTransaction.addToBackStack(null);
                fragmentTransaction.commit();
            } else if (position == 2) {
                Intent All_veickle = new Intent(getActivity(), Activity_Drawer_Dashboard.class);
                Boolean key = true;
                All_veickle.putExtra("total_veickle", key);

                startActivity(All_veickle);
                getActivity().finish();

            } else if (position == 3) {


                Fragment fragment = new Fragment_Main_Alerts();
                FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                fragmentTransaction.replace(R.id.texeting_fram, fragment);
                fragmentTransaction.addToBackStack(null);
                fragmentTransaction.commit();


            } else if (position == 4) {
                Fragment fragment = new Fragment_Main_VEHICLE_Setting();
                FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                fragmentTransaction.replace(R.id.texeting_fram, fragment);
                fragmentTransaction.addToBackStack(null);
                fragmentTransaction.commit();

            } else {
                Fragment fragment = new Fragment_Main_Support();
                FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                fragmentTransaction.replace(R.id.texeting_fram, fragment);
                fragmentTransaction.addToBackStack(null);
                fragmentTransaction.commit();


            }


        }


    });


    return view;
}


private List<ItemObj_for_Dashbord_list> getAllItemObject() {
    List<ItemObj_for_Dashbord_list> items = new ArrayList<>();
    items.add(new ItemObj_for_Dashbord_list(R.drawable.dashbord_icon1, "ADVANCE TRACKING", 0));
    items.add(new ItemObj_for_Dashbord_list(R.drawable.dashbord_icon2, "VEHICLE STATUS", 0));

    items.add(new ItemObj_for_Dashbord_list(R.drawable.dashbord_icon4, "TOTAL VEHICLES", 0));
    items.add(new ItemObj_for_Dashbord_list(R.drawable.dashbord_icon3, "ALERTS", 0));
    items.add(new ItemObj_for_Dashbord_list(R.drawable.dashbord_icon5, "VEHICLE SETTINGS", 0));
    items.add(new ItemObj_for_Dashbord_list(R.drawable.dashbord_icon6, "SUPPORT", 0));


    return items;
}

//****************this is for inflatting nodification count funtionality
public Drawable buildCounterDrawable(int count, int backgroundImageId, Context context) {
    LayoutInflater inflater = LayoutInflater.from(context);
    View view = inflater.inflate(R.layout.menu_counter_menuitem_layout, null);
    view.setBackgroundResource(backgroundImageId);

    if (count == 0 || count >= 100) {
        View counterTextPanel = view.findViewById(R.id.counterValuePanel);
        counterTextPanel.setVisibility(View.GONE);
    } else {
        TextView textView = (TextView) view.findViewById(R.id.count);
        textView.setText("" + count);
    }

    view.measure(
            View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
            View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
    view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());

    view.setDrawingCacheEnabled(true);
    view.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);
    Bitmap bitmap = Bitmap.createBitmap(view.getDrawingCache());
    view.setDrawingCacheEnabled(false);

    return new BitmapDrawable(getResources(), bitmap);
}


@Override
public void onCreateOptionsMenu(
        Menu menu, MenuInflater inflater) {
    inflater.inflate(R.menu.menu_main, menu);
    menu.clear();

    MenuItem item =
            menu.add(Menu.FIRST, R.id.dashboard_nodifycation, 3, "NODIFICATION");
    item.setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
    menu.add(Menu.FIRST, R.id.System_log, 4, "LOGOUT");

    Database_for_GCM_data dbHelper = null;
    dbHelper = new Database_for_GCM_data(getActivity());
    int unread_count = Integer.parseInt(dbHelper.getUnreadCount());
    // calling function for nodification inflater
    item.setIcon(buildCounterDrawable(unread_count, R.drawable.white_nodification, getActivity()));


}

}

片段xml布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center">

    <GridView
        android:id="@+id/dashboard_icon"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:background="#ffffff"
        android:columnWidth="90dp"
        android:focusable="false"
        android:focusableInTouchMode="false"
        android:gravity="center"
        android:horizontalSpacing="1dp"
        android:numColumns="2"
        android:stretchMode="columnWidth"
        android:verticalSpacing="1dp"></GridView>
</LinearLayout>

自定义适配器

public class Custom_Adapter_Dashboard_grid extends BaseAdapter {

private LayoutInflater layoutinflater;
private List<ItemObj_for_Dashbord_list> listStorage;
private Context context;

public Custom_Adapter_Dashboard_grid(Context context, List<ItemObj_for_Dashbord_list> customizedListView) {
    this.context = context;
    try {


        layoutinflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        listStorage = customizedListView;
    } catch (Exception e) {

    }
}

@Override
public int getCount() {

    return listStorage.size();
}

@Override
public Object getItem(int position) {
    return position;
}

@Override
public long getItemId(int position) {
    return position;
}

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

    ViewHolder listViewHolder;
    if (convertView == null) {

        listViewHolder = new ViewHolder();
        convertView = layoutinflater.inflate(R.layout.custom_adapter_dashbord_grid_list, parent, false);
        listViewHolder.screenShot = (ImageView) convertView.findViewById(R.id.icon_image);

        listViewHolder.musicName = (TextView) convertView.findViewById(R.id.icon_name);


        convertView.setTag(listViewHolder);
    } else {
        listViewHolder = (ViewHolder) convertView.getTag();
    }
    listViewHolder.screenShot.setImageResource(listStorage.get(position).getimage());
    listViewHolder.musicName.setText(listStorage.get(position).geticonName());


    return convertView;
}

static class ViewHolder {
    ImageView screenShot;
    TextView musicName;

}

} 自定义适配器布局

<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/card_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
card_view:cardCornerRadius="2dp"
card_view:cardElevation="2dp"
card_view:cardUseCompatPadding="true">

<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:orientation="vertical"
    android:padding="8dp">

    <ImageView
        android:id="@+id/icon_image"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_gravity="center_horizontal"
        android:contentDescription="@string/hello_world"
        android:scaleType="centerCrop" />

    <TextView
        android:id="@+id/icon_name"
        android:layout_width="wrap_content"
        android:layout_height="30dp"
        android:layout_below="@+id/icon_image"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="8dp"
        android:gravity="center_horizontal"
        android:text="sample"
        android:textSize="12sp" />
</LinearLayout>

item obj

public class ItemObj_for_Dashbord_list {

private int dashbord;
private String iconname1;
String unread;


public ItemObj_for_Dashbord_list(int screenShot, String iconname, int unreadcound) {
    dashbord = screenShot;
    iconname1 = iconname;
    unread = String.valueOf(unreadcound);

}

public int getimage() {
    return dashbord;
}

public String geticonName() {
    return iconname1;
}

public String getunreadcount() {
    return unread;
}

}

Android GridView重复图像

3 个答案: