本文实例讲述了Android实现便于批量操作可多选的图片ListView。分享给大家供大家参考,具体如下:
之前项目需要实现一个可多选的图片列表,用户选中一到多张图片后,批量上传。但是网上有可多选普通列表的代码、也有单纯图片列表的代码,却没有两者合并的代码,只好自己实现一个。
废话不说,直接上代码。
先是两个layout:
1、main.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">
<ListView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:focusable="false"
android:id="@+id/lvImageList" >
</ListView>
</LinearLayout>
2、listitem.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="?android:attr/listPreferredItemHeight">
<ImageView
android:id="@+id/itemImgImageInfo"
android:layout_marginTop="4dip"
android:layout_marginBottom="4dip"
android:layout_width="?android:attr/listPreferredItemHeight"
android:layout_height="?android:attr/listPreferredItemHeight">
</ImageView>
<TwoLineListItem xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingLeft="4dip"
android:mode="twoLine">
<CheckedTextView
android:id="@+id/itemChkImageInfo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:textAppearance="?android:attr/textAppearanceSmall"
android:checkMark="?android:attr/listChoiceIndicatorMultiple">
</CheckedTextView>
<TextView
android:id="@+id/itemTxtImageInfo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical|top"
android:layout_marginBottom="4dip"
android:layout_below="@+id/itemChkImageInfo"
android:textAppearance="?android:attr/textAppearanceSmall">
</TextView>
</TwoLineListItem>
</LinearLayout>
接着是代码:
package com.android.MultipleChoiceImageList;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.app.Activity;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.provider.MediaStore.Images;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.CheckedTextView;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;
public class MainActivity extends Activity {
private ListView lvImageList;
private String imageID= "imageID";
private String imageName = "imageName";
private String imageInfo = "imageInfo";
private ArrayList<String> fileNames = new ArrayList<String>();
private MultipleChoiceImageListAdapter mAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
lvImageList=(ListView) this.findViewById(R.id.lvImageList);
lvImageList.setItemsCanFocus(false);
lvImageList.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
CheckedTextView checkedTextView = (CheckedTextView) view.findViewById(R.id.itemChkImageInfo);
checkedTextView.toggle();
mAdapter.setCheckItem(position, checkedTextView.isChecked());
}
});
try{
String[] from = {imageID, imageName, imageInfo};
int[] to = {R.id.itemImgImageInfo, R.id.itemChkImageInfo, R.id.itemTxtImageInfo};
mAdapter = new MultipleChoiceImageListAdapter(MainActivity.this, GetImageList(), R.layout.listitem, from, to);
lvImageList.setAdapter(mAdapter);
}
catch(Exception ex){
return;
}
}
//获取图片列表
private ArrayList<Map<String, String>> GetImageList(){
ArrayList<Map<String, String>> imageList = new ArrayList<Map<String,String>>();
HashMap<String, String> imageMap;
//读取SD卡中所有图片
Uri uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
String[] projection = { MediaStore.Images.Media._ID, MediaStore.Images.Media.DISPLAY_NAME,MediaStore.Images.Media.DATA, MediaStore.Images.Media.SIZE};
String selection = MediaStore.Images.Media.MIME_TYPE + "=?";
String[] selectionArg ={"image/jpeg"};
Cursor mCursor = this.managedQuery(uri, projection, selection, selectionArg, MediaStore.Images.Media.DISPLAY_NAME);
imageList.clear();
if (mCursor != null) {
mCursor.moveToFirst();
while (mCursor.getPosition() != mCursor.getCount())
{
imageMap= new HashMap<String, String>();
imageMap.put(imageID, mCursor.getString(mCursor.getColumnIndex(MediaStore.Images.Media._ID)));
imageMap.put(imageName, mCursor.getString(mCursor.getColumnIndex(MediaStore.Images.Media.DISPLAY_NAME)));
imageMap.put(imageInfo, " " + (mCursor.getLong(mCursor.getColumnIndex(MediaStore.Images.Media.SIZE))/1024)+"KB");
imageList.add(imageMap);
fileNames.add(mCursor.getString(mCursor.getColumnIndex(MediaStore.Images.Media.DATA)));
mCursor.moveToNext();
}
mCursor.close();
}
return imageList;
}
//可多选图片列表适配器
class MultipleChoiceImageListAdapter extends SimpleAdapter {
private Map<Integer, Boolean> map;
private List<Integer> state;
private List<? extends Map<String, ?>> mList;
LayoutInflater mInflater;
public MultipleChoiceImageListAdapter(Context context, List<Map<String, String>> data, int resource, String[] from, int[] to) {
super(context, data, resource, from, to);
map = new HashMap<Integer, Boolean>();
mInflater = LayoutInflater.from(context);
mList = data;
for(int i = 0; i < data.size(); i++) {
map.put(i, false);
}
state = new ArrayList<Integer>();
}
@Override
public int getCount() {
return mList.size();
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
//设置条目选中状态
public void setCheckItem(int position, Boolean isChecked){
map.put(position, isChecked);
if (state.contains(position))
state.remove((Object)position);
if (isChecked){
state.add(position);
}
}
//获取列表中已选中条目
public long[] getCheckItemIds(){
int count = state.size();
long[] ids = new long[count];
for (int i = 0; i < count; i++) {
ids[i]= (long)state.get(i);
}
return ids;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if(convertView == null) {
convertView = mInflater.inflate(R.layout.listitem, null);
}
CheckedTextView checkedTextView = (CheckedTextView) convertView.findViewById(R.id.itemChkImageInfo);
checkedTextView.setChecked(map.get(position));
checkedTextView.setText((String)mList.get(position).get(imageName));
TextView textView = (TextView) convertView.findViewById(R.id.itemTxtImageInfo);
textView.setText((String)mList.get(position).get(imageInfo));
//显示图片缩略图
ImageView image = (ImageView) convertView.findViewById(R.id.itemImgImageInfo);
Bitmap bm = MediaStore.Images.Thumbnails.getThumbnail(getContentResolver(), Long.parseLong((String)mList.get(position).get(imageID)), Images.Thumbnails.MICRO_KIND, null);
image.setImageBitmap(bm);
return convertView;
}
}
}
下面是模拟器上的效果:
由于是初学java和android,代码写得比较糙,请见谅,欢迎指正,不胜感激。
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希望本文所述对大家Android程序设计有所帮助。
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