2010.12.15——— android listView 显示图片

2010.12.15——— android listView 显示图片

需求：在listView里面显示图片

思路：在网上看了一些例子 listView一般继承了SimpleAdapter，SimpleAdapter但是不能直接显示网络上的图片所以我们只需要重写SimpleAdapter里面的一些方法就可以通过url来加载图片了

代码：

item.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="horizontal" android:layout_width="fill_parent"android:layout_height="fill_parent">  <ImageView  android:layout_width="80dip"  android:layout_height="80dip"  android:id="@+id/gcxx_rn"  android:padding="5px"/><LinearLayoutandroid:orientation="vertical" android:layout_width="fill_parent"android:layout_height="wrap_content"><TextView   android:layout_width="fill_parent"  android:layout_height="wrap_content"android:id="@+id/gcmc" android:textSize="16sp"android:textColor="#ffffff"/><TextView   android:layout_width="fill_parent"  android:layout_height="wrap_content"android:id="@+id/jsdw" android:textSize="12sp"android:textColor="#bebebe"/><LinearLayoutandroid:orientation="horizontal" android:layout_width="fill_parent"android:layout_height="wrap_content"><TextView  android:layout_width="50dip"  android:layout_height="wrap_content"android:id="@+id/gczt" android:textSize="12sp"android:textColor="#bebebe"/><TextView   android:layout_width="fill_parent"  android:layout_height="wrap_content"android:id="@+id/jsxz" android:textSize="12sp"android:textColor="#bebebe"/></LinearLayout></LinearLayout></LinearLayout>

list.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:background="#001629"    >       <ListView     android:layout_width="fill_parent"     android:layout_height="wrap_content"     android:id="@+id/dis_listview"    /></LinearLayout>

MySimpleAdapter.java

/* * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package com.huitu.util;import java.io.IOException;import java.net.MalformedURLException;import java.net.URL;import java.util.ArrayList;import java.util.List;import java.util.Map;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.os.AsyncTask;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.Checkable;import android.widget.Filter;import android.widget.Filterable;import android.widget.ImageView;import android.widget.SimpleAdapter;import android.widget.TextView;/** * An easy adapter to map static data to views defined in an XML file. You can specify the data * backing the list as an ArrayList of Maps. Each entry in the ArrayList corresponds to one row * in the list. The Maps contain the data for each row. You also specify an XML file that * defines the views used to display the row, and a mapping from keys in the Map to specific * views. * * Binding data to views occurs in two phases. First, if a * {@link android.widget.SimpleAdapter.ViewBinder} is available, * {@link ViewBinder#setViewValue(android.view.View, Object, String)} * is invoked. If the returned value is true, binding has occurred.  * If the returned value is false, the following views are then tried in order: * [list] * <li> A view that implements Checkable (e.g. CheckBox).  The expected bind value is a boolean. * <li> TextView.  The expected bind value is a string and {@link #setViewText(TextView, String)}  * is invoked. * <li> ImageView. The expected bind value is a resource id or a string and  * {@link #setViewImage(ImageView, int)} or {@link #setViewImage(ImageView, String)} is invoked.  * [/list] * If no appropriate binding can be found, an {@link IllegalStateException} is thrown. */public class MySimpleAdapter extends BaseAdapter implements Filterable {    private int[] mTo;    private String[] mFrom;    private ViewBinder mViewBinder;    private List<? extends Map<String, ?>> mData;    private int mResource;    private int mDropDownResource;    private LayoutInflater mInflater;    private SimpleFilter mFilter;    private ArrayList<Map<String, ?>> mUnfilteredData;    /**     * Constructor     *      * @param context The context where the View associated with this SimpleAdapter is running     * @param data A List of Maps. Each entry in the List corresponds to one row in the list. The     *        Maps contain the data for each row, and should include all the entries specified in     *        "from"     * @param resource Resource identifier of a view layout that defines the views for this list     *        item. The layout file should include at least those named views defined in "to"     * @param from A list of column names that will be added to the Map associated with each     *        item.     * @param to The views that should display column in the "from" parameter. These should all be     *        TextViews. The first N views in this list are given the values of the first N columns     *        in the from parameter.     */    public MySimpleAdapter(Context context, List<? extends Map<String, ?>> data,            int resource, String[] from, int[] to) {        mData = data;        mResource = mDropDownResource = resource;        mFrom = from;        mTo = to;        mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);    }        /**     * @see android.widget.Adapter#getCount()     */    public int getCount() {        return mData.size();    }    /**     * @see android.widget.Adapter#getItem(int)     */    public Object getItem(int position) {        return mData.get(position);    }    /**     * @see android.widget.Adapter#getItemId(int)     */    public long getItemId(int position) {        return position;    }    /**     * @see android.widget.Adapter#getView(int, View, ViewGroup)     */    public View getView(int position, View convertView, ViewGroup parent) {        return createViewFromResource(position, convertView, parent, mResource);    }    private View createViewFromResource(int position, View convertView,            ViewGroup parent, int resource) {        View v;        if (convertView == null) {            v = mInflater.inflate(resource, parent, false);        } else {            v = convertView;        }        bindView(position, v);        return v;    }    /**     * Sets the layout resource to create the drop down views.     *     * @param resource the layout resource defining the drop down views     * @see #getDropDownView(int, android.view.View, android.view.ViewGroup)     */    public void setDropDownViewResource(int resource) {        this.mDropDownResource = resource;    }    @Override    public View getDropDownView(int position, View convertView, ViewGroup parent) {        return createViewFromResource(position, convertView, parent, mDropDownResource);    }    private void bindView(int position, View view) {        final Map dataSet = mData.get(position);        if (dataSet == null) {            return;        }        final ViewBinder binder = mViewBinder;        final String[] from = mFrom;        final int[] to = mTo;        final int count = to.length;        for (int i = 0; i < count; i++) {            final View v = view.findViewById(to[i]);            if (v != null) {                final Object data = dataSet.get(from[i]);                String text = data == null ? "" : data.toString();                if (text == null) {                    text = "";                }                boolean bound = false;                if (binder != null) {                    bound = binder.setViewValue(v, data, text);                }                if (!bound) {                    if (v instanceof Checkable) {                        if (data instanceof Boolean) {                            ((Checkable) v).setChecked((Boolean) data);                        } else if (v instanceof TextView) {                            // Note: keep the instanceof TextView check at the bottom of these                            // ifs since a lot of views are TextViews (e.g. CheckBoxes).                            setViewText((TextView) v, text);                        } else {                            throw new IllegalStateException(v.getClass().getName() +                                    " should be bound to a Boolean, not a " +                                    (data == null ? "<unknown type>" : data.getClass()));                        }                    } else if (v instanceof TextView) {                        // Note: keep the instanceof TextView check at the bottom of these                        // ifs since a lot of views are TextViews (e.g. CheckBoxes).                        setViewText((TextView) v, text);                    } else if (v instanceof ImageView) {                        if (data instanceof Integer) {                            setViewImage((ImageView) v, (Integer) data);                                                    } else {                            setViewImage((ImageView) v, text);                        }                    } else {                        throw new IllegalStateException(v.getClass().getName() + " is not a " +                                " view that can be bounds by this SimpleAdapter");                    }                }            }        }    }    /**     * Returns the {@link ViewBinder} used to bind data to views.     *     * @return a ViewBinder or null if the binder does not exist     *     * @see #setViewBinder(android.widget.SimpleAdapter.ViewBinder)     */    public ViewBinder getViewBinder() {        return mViewBinder;    }    /**     * Sets the binder used to bind data to views.     *     * @param viewBinder the binder used to bind data to views, can be null to     *        remove the existing binder     *     * @see #getViewBinder()     */    public void setViewBinder(ViewBinder viewBinder) {        mViewBinder = viewBinder;    }    /**     * Called by bindView() to set the image for an ImageView but only if     * there is no existing ViewBinder or if the existing ViewBinder cannot     * handle binding to an ImageView.     *     * This method is called instead of {@link #setViewImage(ImageView, String)}     * if the supplied data is an int or Integer.     *     * @param v ImageView to receive an image     * @param value the value retrieved from the data set     *     * @see #setViewImage(ImageView, String)     */    public void setViewImage(ImageView v, int value) {        v.setImageResource(value);    }    /**     * Called by bindView() to set the image for an ImageView but only if     * there is no existing ViewBinder or if the existing ViewBinder cannot     * handle binding to an ImageView.     *     * By default, the value will be treated as an image resource. If the     * value cannot be used as an image resource, the value is used as an     * image Uri.     *     * This method is called instead of {@link #setViewImage(ImageView, int)}     * if the supplied data is not an int or Integer.     *     * @param v ImageView to receive an image     * @param value the value retrieved from the data set     *     * @see #setViewImage(ImageView, int)      */    public void setViewImage(ImageView v, String value) {//        try {//            v.setImageResource(Integer.parseInt(value));//        } catch (NumberFormatException nfe) {//            v.setImageURI(Uri.parse(value));//        }    Bitmap bmp = BitmapFactory.decodeStream(new URL(value).openStream);      v.setImageBitmap(bmp);     }    /**     * Called by bindView() to set the text for a TextView but only if     * there is no existing ViewBinder or if the existing ViewBinder cannot     * handle binding to an TextView.     *     * @param v TextView to receive text     * @param text the text to be set for the TextView     */    public void setViewText(TextView v, String text) {        v.setText(text);    }    public Filter getFilter() {        if (mFilter == null) {            mFilter = new SimpleFilter();        }        return mFilter;    }    /**     * This class can be used by external clients of SimpleAdapter to bind     * values to views.     *     * You should use this class to bind values to views that are not     * directly supported by SimpleAdapter or to change the way binding     * occurs for views supported by SimpleAdapter.     *     * @see SimpleAdapter#setViewImage(ImageView, int)     * @see SimpleAdapter#setViewImage(ImageView, String)     * @see SimpleAdapter#setViewText(TextView, String)     */    public static interface ViewBinder {        /**         * Binds the specified data to the specified view.         *         * When binding is handled by this ViewBinder, this method must return true.         * If this method returns false, SimpleAdapter will attempts to handle         * the binding on its own.         *         * @param view the view to bind the data to         * @param data the data to bind to the view         * @param textRepresentation a safe String representation of the supplied data:         *        it is either the result of data.toString() or an empty String but it         *        is never null         *         * @return true if the data was bound to the view, false otherwise         */        boolean setViewValue(View view, Object data, String textRepresentation);    }    /**     * An array filters constrains the content of the array adapter with     * a prefix. Each item that does not start with the supplied prefix     * is removed from the list.     */    private class SimpleFilter extends Filter {        @Override        protected FilterResults performFiltering(CharSequence prefix) {            FilterResults results = new FilterResults();            if (mUnfilteredData == null) {                mUnfilteredData = new ArrayList<Map<String, ?>>(mData);            }            if (prefix == null || prefix.length() == 0) {                ArrayList<Map<String, ?>> list = mUnfilteredData;                results.values = list;                results.count = list.size();            } else {                String prefixString = prefix.toString().toLowerCase();                ArrayList<Map<String, ?>> unfilteredValues = mUnfilteredData;                int count = unfilteredValues.size();                ArrayList<Map<String, ?>> newValues = new ArrayList<Map<String, ?>>(count);                for (int i = 0; i < count; i++) {                    Map<String, ?> h = unfilteredValues.get(i);                    if (h != null) {                                                int len = mTo.length;                        for (int j=0; j<len; j++) {                            String str =  (String)h.get(mFrom[j]);                                                        String[] words = str.split(" ");                            int wordCount = words.length;                                                        for (int k = 0; k < wordCount; k++) {                                String word = words[k];                                                                if (word.toLowerCase().startsWith(prefixString)) {                                    newValues.add(h);                                    break;                                }                            }                        }                    }                }                results.values = newValues;                results.count = newValues.size();            }            return results;        }        @Override        protected void publishResults(CharSequence constraint, FilterResults results) {            //noinspection unchecked            mData = (List<Map<String, ?>>) results.values;            if (results.count > 0) {                notifyDataSetChanged();            } else {                notifyDataSetInvalidated();            }        }    }}

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