问题
Hi want to create a custom cursor adapter so I can display an image with 2 lines of text. I have had some trouble understanding the custom cursor adapters but I do not understand how to add an imageview to be filled from the path in my database.
回答1:
Will,
I've actually implemented something incredibly similar to what you are looking for. Here is my implementation.
import android.content.Context;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.database.Cursor;
import android.preference.PreferenceManager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class ItemAdapter extends CursorAdapter {
private LayoutInflater mLayoutInflater;
private Context mContext;
public ItemAdapter(Context context, Cursor c) {
super(context, c);
mContext = context;
mLayoutInflater = LayoutInflater.from(context);
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
View v = mLayoutInflater.inflate(R.layout.items_row, parent, false);
return v;
}
/**
* @author will
*
* @param v
* The view in which the elements we set up here will be displayed.
*
* @param context
* The running context where this ListView adapter will be active.
*
* @param c
* The Cursor containing the query results we will display.
*/
@Override
public void bindView(View v, Context context, Cursor c) {
String title = c.getString(c.getColumnIndexOrThrow(ItemDbAdapter.KEY_TITLE));
String date = c.getString(c.getColumnIndexOrThrow(ItemDbAdapter.KEY_DATE));
String imagePath = c.getString(c.getColumnIndexOrThrow(ItemDbAdapter.KEY_IMG));
int deletion = c.getInt(c.getColumnIndexOrThrow(ItemDbAdapter.KEY_DELETION));
int priority = c.getInt(c.getColumnIndexOrThrow(ItemDbAdapter.KEY_PRIORITY));
/**
* Next set the title of the entry.
*/
TextView title_text = (TextView) v.findViewById(R.id.item_text);
if (title_text != null) {
title_text.setText(title);
}
/**
* Set Date
*/
TextView date_text = (TextView) v.findViewById(R.id.item_date);
if (date_text != null) {
date_text.setText(date);
}
/**
* Decide if we should display the paper clip icon denoting image attachment
*/
ImageView item_image = (ImageView) v.findViewById(R.id.item_attachment);
item_image.setVisibility(ImageView.INVISIBLE);
if (imagePath != null && imagePath.length() != 0 && item_image != null) {
item_image.setVisibility(ImageView.VISIBLE);
}
/**
* Decide if we should display the deletion indicator
*/
ImageView del_image = (ImageView) v.findViewById(R.id.item_deletion);
del_image.setVisibility(ImageView.INVISIBLE);
if (deletion == 1) {
del_image.setVisibility(ImageView.VISIBLE);
}
}
}
XML just incase...
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:background="@drawable/list_bg">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView android:id="@+id/item_text"
android:layout_width="200dp"
android:layout_height="wrap_content"
android:lines="1"
android:scrollHorizontally="true"
android:ellipsize="end"
android:paddingLeft="2sp"
android:paddingTop="2sp"
android:textSize="18sp"
android:textStyle="bold"
android:shadowColor="#90909090"
android:shadowDx="1.0"
android:shadowDy="1.0"
android:shadowRadius="1.0"/>
<TextView android:id="@+id/item_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="12sp"
android:textColor="#FF808080"
android:paddingLeft="2sp"
android:paddingTop="2sp"/>
</LinearLayout>
<ImageView android:id="@+id/item_deletion"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/deletion"
android:visibility="invisible"
android:layout_centerVertical="true"
android:layout_alignParentRight="true"
android:paddingRight="5sp"/>
<ImageView android:id="@+id/item_attachment"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/attachment"
android:visibility="invisible"
android:layout_centerVertical="true"
android:layout_toLeftOf="@id/item_deletion"/>
</RelativeLayout>
This displays two rows of text and up to 2 images to the right of the text depending on certain conditions.
I hope this can give you a basis to work from!
Good luck :]
回答2:
Check what I have done:
BTW: CheckpointsView.getImageResId() returns a valid drawable reference
public class CheckpointCursorAdapter extends ResourceCursorAdapter {
private int layoutType = 0;
public static final int BLOTTER = 1;
public static final int DAY = 2;
public static final int MONTH = 3;
public static final int OVERVIEW = 4;
public static final int LAYOUT_ID = R.layout.checkpoint_row;
public CheckpointCursorAdapter(Context context, int layoutType, Cursor cursor) {
super(context, LAYOUT_ID, cursor);
this.layoutType = layoutType;
}
@Override
public View newView(Context context, Cursor cur, ViewGroup parent) {
LayoutInflater li = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
return li.inflate(LAYOUT_ID, parent, false);
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
TextView tvListText = (TextView) view.findViewById(R.id.txtCheckPoint);
Date dt = new Date(cursor.getLong(cursor.getColumnIndex(DatabaseHelper.KEY_CHECKPOINT)));
switch (layoutType) {
case BLOTTER:
tvListText.setText(dt.toLocaleString());
((ImageView) view.findViewById(R.id.imgCheckpointInOut))
.setImageResource(CheckpointsView.getImageResId(cursor.getCount()
- cursor.getPosition()));
break;
case DAY:
tvListText.setText(new SimpleDateFormat("HH:mm:ss").format(dt));
((ImageView) view.findViewById(R.id.imgCheckpointInOut))
.setImageResource(CheckpointsView.getImageResId(cursor.getPosition() + 1));
break;
case MONTH:
tvListText.setText(new SimpleDateFormat("MMM dd HH:mm:ss").format(dt));
((ImageView) view.findViewById(R.id.imgCheckpointInOut))
.setImageResource(CheckpointsView.getImageResId(cursor.getPosition() + 1));
break;
case OVERVIEW:
break;
}
}
}
And the XML just in case
<?xml version="1.0" encoding="utf-8"?>
<TextView android:id="@+id/txtCheckPoint"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:textSize="20dp" android:padding="8dp" android:textStyle="bold">
</TextView>
<LinearLayout android:layout_width="fill_parent"
android:layout_height="wrap_content" android:orientation="horizontal"
android:gravity="right" android:layout_weight="1"
android:layout_marginRight="8px">
<TextView android:id="@+id/txtTotalHours"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:textSize="20dp" android:padding="8dp" android:paddingRight="12dp">
</TextView>
<TextView android:id="@+id/txtHourBalanceRow"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:textSize="12dp" android:padding="8dp">
</TextView>
<ImageView android:id="@+id/imgCheckpointInOut"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:src="@drawable/black_clock" />
</LinearLayout>
You can check the whole code at: http://code.google.com/p/droidtimesheet/
回答3:
Adding images and text is not specific to CursorAdapter; you use the same technique for any kind of adapter. You can create a layout for your row and inflate it inside your getView method. The APIDemos sample project, contained in the Android SDK android-sdk-PLATFORM/samples/android-XY/ApiDemos folder, does what you want. You can find the row definitons in list_item_icon_text.xml. Here is copy of file content (w/o the license).
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView android:id="@+id/icon"
android:layout_width="48dip"
android:layout_height="48dip" />
<TextView android:id="@+id/text"
android:layout_gravity="center_vertical"
android:layout_width="0dip"
android:layout_weight="1.0"
android:layout_height="wrap_content" />
</LinearLayout>
回答4:
Here is a great tutorial that I have used before to help with my custom list adapters. It sounds like it is doing the exact same thing you want to do. The tutorial shows how to build a custom list adapter with an image and two lines of text.
来源：https://stackoverflow.com/questions/5300787/how-do-i-create-a-custom-cursor-adapter-for-a-listview-for-use-with-images-and-t