发布于 2016-03-04 22:34:48 | 126 次阅读 | 评论: 0 | 来源: 网友投递
Android移动端操作系统
Android是一种基于Linux的自由及开放源代码的操作系统，主要使用于移动设备，如智能手机和平板电脑，由Google公司和开放手机联盟领导及开发。尚未有统一中文名称，中国大陆地区较多人使用“安卓”或“安致”。
本文实例讲述了Android实现滑动加载数据的方法。分享给大家供大家参考。具体实现方法如下：
EndLessActivity.java如下：
package com.ScrollListView;
import Android.app.ListActivity;
import Android.os.Bundle;
import Android.view.Gravity;
import Android.view.View;
import Android.view.ViewGroup;
import Android.widget.AbsListView;
import Android.widget.BaseAdapter;
import Android.widget.LinearLayout;
import Android.widget.ProgressBar;
import Android.widget.TextView;
import Android.widget.AbsListView.OnScrollListener;
public class EndLessActivity extends ListActivity implements OnScrollListener {
Aleph0 adapter = new Aleph0();
int mProgressStatus = 0 ;
ProgressBar progressBar;
protected void onCreate(Bundle savedInstanceState) {
super .onCreate(savedInstanceState);
LinearLayout searchLayout = new LinearLayout( this );
searchLayout.setOrientation(LinearLayout.HORIZONTAL);
progressBar = new ProgressBar( this );
progressBar.setPadding( 0 , 0 , 15 , 0 );
searchLayout.addView(progressBar, new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
));
TextView textView = new TextView( this );
textView.setText( " 加载中... " );
textView.setGravity(Gravity.CENTER_VERTICAL);
searchLayout.addView(textView, new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.FILL_PARENT,
LinearLayout.LayoutParams.FILL_PARENT
));
searchLayout.setGravity(Gravity.CENTER);
LinearLayout loadingLayout = new LinearLayout( this );
loadingLayout.addView(searchLayout, new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
));
loadingLayout.setGravity(Gravity.CENTER);
getListView().addFooterView(loadingLayout);
setListAdapter(adapter);
getListView().setOnScrollListener( this );
}
public void onScroll(AbsListView view,
int firstVisible, int visibleCount, int totalCount) {
boolean loadMore = /* maybe add a padding */
firstVisible + visibleCount >= totalCount;
if (loadMore) {
adapter.count += visibleCount; // or any other amount
adapter.notifyDataSetChanged();
}
}
public void onScrollStateChanged(AbsListView v, int s) { }
class Aleph0 extends BaseAdapter {
int count = 40 ; /* starting amount */
public int getCount() { return count; }
public Object getItem( int pos) { return pos; }
public long getItemId( int pos) { return pos; }
public View getView( int pos, View v, ViewGroup p) {
TextView view = new TextView(EndLessActivity. this );
view.setText( " entry " + pos);
return view;
}
}
}
listview下部是按钮控制：
package com.ScrollListView;
import Android.app.ListActivity;
import Android.os.Bundle;
import Android.view.Gravity;
import Android.view.View;
import Android.view.ViewGroup;
import Android.widget.AbsListView;
import Android.widget.BaseAdapter;
import Android.widget.Button;
import Android.widget.LinearLayout;
import Android.widget.ProgressBar;
import Android.widget.TextView;
import Android.widget.AbsListView.OnScrollListener;
public class EndLessActivity extends ListActivity {
Aleph0 adapter = new Aleph0();
int mProgressStatus = 0 ;
protected void onCreate(Bundle savedInstanceState) {
super .onCreate(savedInstanceState);
LinearLayout searchLayout = new LinearLayout( this );
searchLayout.setOrientation(LinearLayout.HORIZONTAL);
Button textView = new Button( this );
textView.setText( " 加载中... " );
textView.setGravity(Gravity.CENTER_VERTICAL);
searchLayout.addView(textView, new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.FILL_PARENT,
LinearLayout.LayoutParams.FILL_PARENT
));
searchLayout.setGravity(Gravity.CENTER);
LinearLayout loadingLayout = new LinearLayout( this );
loadingLayout.addView(searchLayout, new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
));
loadingLayout.setGravity(Gravity.CENTER);
getListView().addFooterView(loadingLayout);
textView.setOnClickListener( new Button.OnClickListener()
{ @Override
public void onClick(View v)
{
adapter.count += 10 ;
adapter.notifyDataSetChanged();
}
});
setListAdapter(adapter);
// getListView().setOnScrollListener(this);
}
/* public void onScroll(AbsListView view,
int firstVisible, int visibleCount, int totalCount) {
boolean loadMore =
firstVisible + visibleCount >= totalCount;
if(loadMore) {
adapter.count += visibleCount;
adapter.notifyDataSetChanged();
}
} */
public void onScrollStateChanged(AbsListView v, int s) { }
class Aleph0 extends BaseAdapter {
int count = 40 ; /* starting amount */
public int getCount() { return count; }
public Object getItem( int pos) { return pos; }
public long getItemId( int pos) { return pos; }
public View getView( int pos, View v, ViewGroup p) {
TextView view = new TextView(EndLessActivity. this );
view.setText( " entry " + pos);
return view;
}
}
}
希望本文所述对大家的Android程序设计有所帮助。