触碰模式下的listview的选中项背景高亮
2016-01-13 16:07
543 查看
我在工作中发现:触碰模式下的listview项无法被选中,所谓选中,意思是点击选中该项后,背景长期高亮。
在模拟器上测试时,可以使用鼠标滑轮滚动选中,这会调用onItemSelected()方法,在这里可以设置选中项高亮。
在真机上,由于没有滑轮,只能用手指点击选中,但是点击时,不会有选中后高亮的效果(注意:选中后高亮不是指点击选中那一下高亮,而是点击后长期高亮)。
或许你会想到使用selector背景选择器来设置:
[html] view
plaincopy
<?xml version="1.0" encoding="utf-8" ?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!-- 默认时的背景图片-->
<item android:drawable="@drawable/pic1" />
<!-- 没有焦点时的背景图片-->
<item android:state_window_focused="false" android:drawable="@drawable/pic1" />
<!-- 非触摸模式下获得焦点并单击时的背景图片-->
<item android:state_focused="true" android:state_pressed="true"
android:drawable="@drawable/pic2" />
<!-- 触摸模式下单击时的背景图片-->
<item android:state_focused="false" android:state_pressed="true"
android:drawable="@drawable/pic3" />
<!--选中时的图片背景-->
<item android:state_selected="true" android:drawable="@drawable/pic4" />
<!--获得焦点时的图片背景-->
<item android:state_focused="true" android:drawable="@drawable/pic5" />
</selector>
悲剧的是:我无法使用selector实现我想要的那种选中后长期高亮的状态
于是我只能在java代码中寻求思路了
下面的代码实现listview单选模式下点击后背景图片长期高亮
[java] view
plaincopy
package org.yaoming.listview;
import org.yaoming.util.Common;
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
public class Listview_selectorActivity extends Activity implements OnItemClickListener {
private String[] arrays;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
arrays = new String[] {"a","b","c","d","e"};
//使用SharedPreferences是为了每次点击退出时都保存之前选中的项,以后一打开时就可以看到以前的选择
SharedPreferences sp = getSharedPreferences("testListview", 0);
Common.SELECTED = sp.getInt("selected", Common.SELECTED);
ListView listview = (ListView) findViewById(R.id.listView1);
listview.setAdapter(new MyAdapter(this));
listview.setOnItemClickListener(this);
}
public class MyAdapter extends BaseAdapter{
Context context;
public class ViewHolder{
TextView tv;
ImageView iv;
}
public MyAdapter(Context context){
this.context = context;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return arrays.length;
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
//通过日志测试,原来每次点击listview的每一项,这里都会运行
//通过查看源码,原来是getItemAtPosition()中getAdapter()搞的鬼
Log.i("listview", "zhixingguo ");
LinearLayout layout;
ViewHolder viewholder;
if(null == convertView){
layout = (LinearLayout) LayoutInflater.from(context).inflate(R.layout.item, null);
viewholder = new ViewHolder();
viewholder.tv = (TextView) layout.findViewById(R.id.textView2);
viewholder.iv = (ImageView) layout.findViewById(R.id.imageView1);
convertView = layout;
layout.setTag(viewholder);
}else{
layout = (LinearLayout) convertView;
viewholder = (ViewHolder) layout.getTag();
}
viewholder.tv.setText(arrays[position]);
//在这里加个判断,若为选中项,则改变背景图片和背景色
if(Common.SELECTED == position){
viewholder.iv.setBackgroundResource(R.drawable.asi);
layout.setBackgroundResource(R.color.blue);
}else {
viewholder.iv.setBackgroundResource(R.drawable.icon);
layout.setBackgroundResource(R.color.transparent);
}
return convertView;
}
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
//如果在这里简单地通过findviewbyid()改变背景图片,点击时会出现图片乱显示的情况
// ImageView iv = (ImageView) view.findViewById(R.id.imageView1);
// iv.setImageResource(R.drawable.asi);
//改变SELECTED的值,并在getview里判断加载的位置是否为选中的位置
Common.SELECTED = position;
}
}
还有一个自定义的util类
[java] view
plaincopy
package org.yaoming.util;
public class Common {
public static int SELECTED = -1;
}
另外,main.xml的代码:
[html] view
plaincopy
<?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">
<TextView android:layout_width="fill_parent"
android:layout_height="wrap_content" android:text="@string/hello" />
<ListView android:id="@+id/listView1" android:choiceMode="singleChoice"
android:cacheColorHint="#00000000" android:layout_height="wrap_content"
android:layout_width="match_parent"></ListView>
</LinearLayout>
listview的item布局:
[html] view
plaincopy
<?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">
<TextView android:text="TextView"
android:id="@+id/textView2" android:textSize="30sp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"></TextView>
<ImageView android:src="@drawable/icon"
android:layout_width="wrap_content" android:id="@+id/imageView1"
android:layout_height="wrap_content"></ImageView>
</LinearLayout>
不使用selector,直接在java代码里设置。在onItemClick的时候获得position,并在getview判断是否为选中项,设置背景颜色高亮,记得布局文件中listview要设置成singleChoiceMode。
值得注意的是,onItemClick会触发getItemAtPosition方法
[java] view
plaincopy
/**
* Callback method to be invoked when an item in this AdapterView has
* been clicked.
* <p>
* Implementers can call getItemAtPosition(position) if they need
* to access the data associated with the selected item.
*
* @param parent The AdapterView where the click happened.
* @param view The view within the AdapterView that was clicked (this
* will be a view provided by the adapter)
* @param position The position of the view in the adapter.
* @param id The row id of the item that was clicked.
*/
void onItemClick(AdapterView<?> parent, View view, int position, long id);
}
而getItemAtPosition又会调用getAdapter方法,就相当于重新刷新一次ui中的listview
[java] view
plaincopy
/**
* Gets the data associated with the specified position in the list.
*
* @param position Which data to get
* @return The data associated with the specified position in the list
*/
public Object getItemAtPosition(int position) {
T adapter = getAdapter();
return (adapter == null || position < 0) ? null : adapter.getItem(position);
}
实现效果如下:
下面是源码下载地址
http://download.csdn.net/detail/iamkila/4034770
原文:http://blog.csdn.net/iamkila/article/details/7218351
在模拟器上测试时,可以使用鼠标滑轮滚动选中,这会调用onItemSelected()方法,在这里可以设置选中项高亮。
在真机上,由于没有滑轮,只能用手指点击选中,但是点击时,不会有选中后高亮的效果(注意:选中后高亮不是指点击选中那一下高亮,而是点击后长期高亮)。
或许你会想到使用selector背景选择器来设置:
[html] view
plaincopy
<?xml version="1.0" encoding="utf-8" ?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!-- 默认时的背景图片-->
<item android:drawable="@drawable/pic1" />
<!-- 没有焦点时的背景图片-->
<item android:state_window_focused="false" android:drawable="@drawable/pic1" />
<!-- 非触摸模式下获得焦点并单击时的背景图片-->
<item android:state_focused="true" android:state_pressed="true"
android:drawable="@drawable/pic2" />
<!-- 触摸模式下单击时的背景图片-->
<item android:state_focused="false" android:state_pressed="true"
android:drawable="@drawable/pic3" />
<!--选中时的图片背景-->
<item android:state_selected="true" android:drawable="@drawable/pic4" />
<!--获得焦点时的图片背景-->
<item android:state_focused="true" android:drawable="@drawable/pic5" />
</selector>
悲剧的是:我无法使用selector实现我想要的那种选中后长期高亮的状态
于是我只能在java代码中寻求思路了
下面的代码实现listview单选模式下点击后背景图片长期高亮
[java] view
plaincopy
package org.yaoming.listview;
import org.yaoming.util.Common;
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
public class Listview_selectorActivity extends Activity implements OnItemClickListener {
private String[] arrays;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
arrays = new String[] {"a","b","c","d","e"};
//使用SharedPreferences是为了每次点击退出时都保存之前选中的项,以后一打开时就可以看到以前的选择
SharedPreferences sp = getSharedPreferences("testListview", 0);
Common.SELECTED = sp.getInt("selected", Common.SELECTED);
ListView listview = (ListView) findViewById(R.id.listView1);
listview.setAdapter(new MyAdapter(this));
listview.setOnItemClickListener(this);
}
public class MyAdapter extends BaseAdapter{
Context context;
public class ViewHolder{
TextView tv;
ImageView iv;
}
public MyAdapter(Context context){
this.context = context;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return arrays.length;
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
//通过日志测试,原来每次点击listview的每一项,这里都会运行
//通过查看源码,原来是getItemAtPosition()中getAdapter()搞的鬼
Log.i("listview", "zhixingguo ");
LinearLayout layout;
ViewHolder viewholder;
if(null == convertView){
layout = (LinearLayout) LayoutInflater.from(context).inflate(R.layout.item, null);
viewholder = new ViewHolder();
viewholder.tv = (TextView) layout.findViewById(R.id.textView2);
viewholder.iv = (ImageView) layout.findViewById(R.id.imageView1);
convertView = layout;
layout.setTag(viewholder);
}else{
layout = (LinearLayout) convertView;
viewholder = (ViewHolder) layout.getTag();
}
viewholder.tv.setText(arrays[position]);
//在这里加个判断,若为选中项,则改变背景图片和背景色
if(Common.SELECTED == position){
viewholder.iv.setBackgroundResource(R.drawable.asi);
layout.setBackgroundResource(R.color.blue);
}else {
viewholder.iv.setBackgroundResource(R.drawable.icon);
layout.setBackgroundResource(R.color.transparent);
}
return convertView;
}
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
//如果在这里简单地通过findviewbyid()改变背景图片,点击时会出现图片乱显示的情况
// ImageView iv = (ImageView) view.findViewById(R.id.imageView1);
// iv.setImageResource(R.drawable.asi);
//改变SELECTED的值,并在getview里判断加载的位置是否为选中的位置
Common.SELECTED = position;
}
}
还有一个自定义的util类
[java] view
plaincopy
package org.yaoming.util;
public class Common {
public static int SELECTED = -1;
}
另外,main.xml的代码:
[html] view
plaincopy
<?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">
<TextView android:layout_width="fill_parent"
android:layout_height="wrap_content" android:text="@string/hello" />
<ListView android:id="@+id/listView1" android:choiceMode="singleChoice"
android:cacheColorHint="#00000000" android:layout_height="wrap_content"
android:layout_width="match_parent"></ListView>
</LinearLayout>
listview的item布局:
[html] view
plaincopy
<?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">
<TextView android:text="TextView"
android:id="@+id/textView2" android:textSize="30sp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"></TextView>
<ImageView android:src="@drawable/icon"
android:layout_width="wrap_content" android:id="@+id/imageView1"
android:layout_height="wrap_content"></ImageView>
</LinearLayout>
不使用selector,直接在java代码里设置。在onItemClick的时候获得position,并在getview判断是否为选中项,设置背景颜色高亮,记得布局文件中listview要设置成singleChoiceMode。
值得注意的是,onItemClick会触发getItemAtPosition方法
[java] view
plaincopy
/**
* Callback method to be invoked when an item in this AdapterView has
* been clicked.
* <p>
* Implementers can call getItemAtPosition(position) if they need
* to access the data associated with the selected item.
*
* @param parent The AdapterView where the click happened.
* @param view The view within the AdapterView that was clicked (this
* will be a view provided by the adapter)
* @param position The position of the view in the adapter.
* @param id The row id of the item that was clicked.
*/
void onItemClick(AdapterView<?> parent, View view, int position, long id);
}
而getItemAtPosition又会调用getAdapter方法,就相当于重新刷新一次ui中的listview
[java] view
plaincopy
/**
* Gets the data associated with the specified position in the list.
*
* @param position Which data to get
* @return The data associated with the specified position in the list
*/
public Object getItemAtPosition(int position) {
T adapter = getAdapter();
return (adapter == null || position < 0) ? null : adapter.getItem(position);
}
实现效果如下:
下面是源码下载地址
http://download.csdn.net/detail/iamkila/4034770
原文:http://blog.csdn.net/iamkila/article/details/7218351
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