将联系人的图片加载到ListView(第2部分)

时间:2012-05-24 17:38:02

标签: android image contactscontract

我根据那里的答案修改了the code in this question,以便在ListView上加载联系人的图片。我正在获取Photo_id,并使用它来获取联系人的位图,使用loadContactPhoto(ContentResolver cr,long id)。问题是没有ImageView获得新图像,尽管照片ID总是不同的。我尝试使用Contact._ID,但仍然只有两个联系人'ImageView有联系人图片,他们都错了。我评论了我在下面添加的新行。

以下是编辑后的代码:

ContactStock:

public class ContactStock {

private String name;
private String number;
private Bitmap picture;


public ContactStock(String name, String number) {
    this.name = name;
    this.number = number;
}

public ContactStock(String name, String number, Bitmap photo) {
    this.name = name;
    this.number = number;
    this.picture = photo;
}

public void setName(String name) {
    this.name = name;
}

public void setNumber(String number) {
    this.number = number;
}

public String getName() {
    return this.name;
}

public String getNumber() {
    return this.number;
}

public void setPicture(Bitmap picture) { // NEW METHOD
    this.picture = picture;
}

public Bitmap getPicture() { // NEW METHOD
    return picture;
}
}

addlistfromcontact:

    public class addlistfromcontact extends Activity {
private ListView lst;
private List<ContactStock> contactstock;
private Cursor mCursor;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.tab_contact_list);
    lst = (ListView) findViewById(R.id.tab_contact_list);
    contactstock = new ArrayList<ContactStock>();

    mCursor = managedQuery(ContactsContract.Data.CONTENT_URI, null,
            Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'", null,
            ContactsContract.Data.DISPLAY_NAME + " ASC");

    int number = mCursor.getColumnIndex(Phone.NUMBER);
    int name = mCursor.getColumnIndex(ContactsContract.Data.DISPLAY_NAME);
    int id = mCursor.getColumnIndex(Contacts.PHOTO_ID); // NEW LINE

    while (mCursor.moveToNext()) {

        String phName = mCursor.getString(name);
        String phNumber = mCursor.getString(number);
        long phId = mCursor.getLong(id); // NEW LINE

        Bitmap phPhoto = loadContactPhoto(getContentResolver(), phId); // NEW LINE
        Log.d("phId=", phId + "");

        contactstock.add(new ContactStock(phName, phNumber, phPhoto)); // NEW LINE EDIT
    }
    lst.setAdapter(new ContactListAdapter(addlistfromcontact.this,
            contactstock));
}

public static Bitmap loadContactPhoto(ContentResolver cr, long id) { // NEW METHOD
    Uri uri = ContentUris.withAppendedId(
            ContactsContract.Contacts.CONTENT_URI, id);
    InputStream input = ContactsContract.Contacts
            .openContactPhotoInputStream(cr, uri);
    if (input == null) {
        return null;
    }
    return BitmapFactory.decodeStream(input);
}

    }

ContactListAdapter:

public class ContactListAdapter extends ArrayAdapter {
    private final Activity activity;
    private final List stocks;

    public ContactListAdapter(Activity activity, List objects) {
        super(activity, R.layout.listview_detail_tab_contact_list, objects);
        this.activity = activity;
        this.stocks = objects;
    }

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

        View rowView = convertView;
        ContactStockView sv = null;
        if (rowView == null) {
            // Get a new instance of the row layout view
            LayoutInflater inflater = activity.getLayoutInflater();
            rowView = inflater.inflate(
                    R.layout.listview_detail_tab_contact_list, null);

            // Hold the view objects in an object,
            // so they don't need to be re-fetched
            sv = new ContactStockView();
            sv.name = (TextView) rowView.findViewById(R.id.contact_name);
            sv.number = (TextView) rowView.findViewById(R.id.contact_number);
            sv.photo = (ImageView) rowView.findViewById(R.id.contact_photo);

            // Cache the view objects in the tag,
            // so they can be re-accessed later
            rowView.setTag(sv);
        } else {
            sv = (ContactStockView) rowView.getTag();
        }
        // Transfer the stock data from the data object
        // to the view objects
        ContactStock currentStock = (ContactStock) stocks.get(position);
        sv.name.setText(currentStock.getName());
        sv.number.setText(currentStock.getNumber());
        sv.photo.setImageBitmap(currentStock.getPicture()); // NEW LINE

        // TODO Auto-generated method stub
        return rowView;
    }

    protected static class ContactStockView {
        protected TextView name;
        protected TextView number;
        protected ImageView photo; // NEW LINE
    }
}

2 个答案:

答案 0 :(得分:1)

您的代码中存在两个问题。第一个很容易克服,其他人需要更多的工作。

让我们从简单的开始: 方法ContactsContract.Contacts.openContactPhotoInputStream(cr, uri)采用联系人uri而非照片uri。这是您致ContentUris.withAppendedId(ContactsContract.Contacts.CONTENT_URI, id)的ID必须是联系人ID。

在迭代结果集时,您还会创建许多Bitmap个对象。不要这样做。虽然这可能最初起作用,但当列表变长时,它可能会因OutOfMemory错误而崩溃。尝试根据需要创建尽可能少的Bitmap个对象。即:仅适用于那些可见的行。滚动列表视图时,您必须回收现有的位图。

答案 1 :(得分:0)

由于我在确定如何在没有任何UI冻结的情况下有效加载所有联系人的照片时遇到了很多麻烦,当我第一次开始使用Android时加载图像时出现错误,我强烈建议任何看我的问题的人都要好好看看here

这是一个示例应用程序,它教您如何处理所有处理数据并有效地加载图像,在滚动列表时没有任何“打嗝”。这也是一个让你开始使用Android的好项目!

具体来说,对于我的问题代码的联系人图像部分,API提供了两个简单的方法here,它们返回联系人的高分辨率图像或缩略图的InputStream。您所要做的就是使用BitmapFactory.decodeByteArray()对其进行解码。请记住加载您需要在应用中使用的图像大小(上面的链接中描述的内容),这样您就不会得到OutOfMemoryError!

为了进一步改进代码,您还可以使用自定义Cursor适配器替换ArrayAdapter,并且只在现场加载您需要的listView行。