童贞apk纠结过的技术点<2> - ListView中加下加FootView和点击...- listView 不同ltem展示不同的数据

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▪童贞apk纠结过的技术点<2&gt 处女apk纠结过的技术点<2> android json 解析 android自带json解析类，和java的使用有那么点区别，主要在.........

▪ ListView中加下加FootView和点击按钮动态加载listview ListView中加上加FootView和点击按钮动态加载listview package hbq.android.myapp.listview; import android.app.ListActivity; import android.os.Bundle; import android.util.Log; import android.view.Gravity; import android.view.View; import and.........

▪ listView 不同ltem展示不同的数据 listView 不同ltem显示不同的数据请下载附件 ......

[1]童贞apk纠结过的技术点<2&gt

来源: 互联网发布时间: 2014-02-18

处女apk纠结过的技术点<2>

android json 解析

android自带json解析类，和java的使用有那么点区别，主要在实例化的时候看代码

public static JSONArray jsonAnalyze(String result) {
  JSONObject jsonObj;
  try {
   jsonObj = new JSONObject(result);//直接实例化
   String suc = jsonObj.getString("success");
   Log.i("success", suc);

   int count = jsonObj.getInt("totalCount");
   Log.i("totalCount", String.valueOf(count));
   JSONArray jobjData = jsonObj.getJSONArray("rows");    //解析获取数组
   return jobjData;
  } catch (JSONException e1) {
   e1.printStackTrace();
   return null;
  }
}

[2] ListView中加下加FootView和点击按钮动态加载listview

来源: 互联网发布时间: 2014-02-18

ListView中加上加FootView和点击按钮动态加载listview

package hbq.android.myapp.listview;


import android.app.ListActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.LinearLayout.LayoutParams;
/**
 * 
 * @author huangbq
 *
 */
public class ButtonLoadingActivity extends ListActivity    {
	private static final String TAG = "ButtonLoadingActivity";
       
    private listViewAdapter adapter = new listViewAdapter();
    private ListView listView ;
    /**
	 * 设置布局显示的属性
	 */
    private LayoutParams mLayoutParams =new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
    /**
	 * 设置布局显示目标最大化属性
	 */
    private LayoutParams FFlayoutParams =new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT,LinearLayout.LayoutParams.FILL_PARENT);
    
    protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
             Log.i(TAG, "onCreate(Bundle savedInstanceState)>>>>>>>>>>>>>>>" );
              LinearLayout layout = new LinearLayout(this);
              layout.setOrientation(LinearLayout.HORIZONTAL);
             
              Button button = new Button(this);
              button.setText("点击加载下10条...");
              button.setGravity(Gravity.CENTER_VERTICAL);
               
              layout.addView(button,FFlayoutParams);
              layout.setGravity(Gravity.CENTER);
              LinearLayout loadingLayout = new LinearLayout(this);
              loadingLayout.addView(layout,mLayoutParams);
              loadingLayout.setGravity(Gravity.CENTER);
               
               
              listView = getListView();
               
              listView.addFooterView(loadingLayout);
               
              button.setOnClickListener(new Button.OnClickListener()   
              {         @Override      
                 public void onClick(View v)  
              {         
                  adapter.count += 10;  
                  Log.i(TAG, "setOnClickListener:" +  adapter.count);
                  adapter.notifyDataSetChanged();
				  int currentPage=adapter.count/10;
				  Toast.makeText(getApplicationContext(), "第"+currentPage+"页", Toast.LENGTH_LONG).show();
                  }      
              });  
             
          setListAdapter(adapter);  
     }  

    class listViewAdapter extends BaseAdapter {
        int count = 10; /* 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) {
			Log.i(TAG, "getView>>>pos:" + pos);
			TextView view;
			if (v==null) {
				view = new TextView(ButtonLoadingActivity.this);
			}
			else {
				view=(TextView)v;
			}
			view.setText("ListItem " + pos);
			view.setTextSize(20f);
			view.setGravity(Gravity.CENTER);
			view.setHeight(60);
			return view;
         }
     }



}

2.用OnScrollListener来监听是不是最后一条项目来加载

package hbq.android.myapp.listview;

import android.app.ListActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.widget.AbsListView;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.AbsListView.OnScrollListener;
import android.widget.LinearLayout.LayoutParams;
/**
 * 
 * @author huangbq
 *
 */
public class MainActivity extends ListActivity implements OnScrollListener {
	
	private static final String TAG = "MainActivity";
	private listViewAdapter adapter = new listViewAdapter();
	ListView listView ;
	private int lastItem = 0;
	LinearLayout loadingLayout;
	/**
	 * 设置布局显示属性
	 */
    private LayoutParams mLayoutParams =new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
    /**
	 * 设置布局显示目标最大化属性
	 */
    private LayoutParams FFlayoutParams =new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT,LinearLayout.LayoutParams.FILL_PARENT);
    
	private ProgressBar progressBar;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		Log.i(TAG, "onCreate(Bundle savedInstanceState)>>>>>>>>>>>>>>>" );
	    //线性布局
		LinearLayout layout = new LinearLayout(this);
	   //设置布局 水平方向
		layout.setOrientation(LinearLayout.HORIZONTAL);
		 //进度条
		progressBar = new ProgressBar(this);
		 //进度条显示位置
		progressBar.setPadding(0, 0, 15, 0);
		//把进度条加入到layout中
		layout.addView(progressBar, mLayoutParams);
		//文本内容
		TextView textView = new TextView(this);
		textView.setText("加载中...");
		textView.setGravity(Gravity.CENTER_VERTICAL);
		//把文本加入到layout中
		layout.addView(textView, FFlayoutParams);
		//设置layout的重力方向，即对齐方式是
		layout.setGravity(Gravity.CENTER);
		
		//设置ListView的页脚layout
		loadingLayout = new LinearLayout(this);
		loadingLayout.addView(layout, mLayoutParams);
		loadingLayout.setGravity(Gravity.CENTER);
		loadingLayout.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				if (adapter.count<=41) {
					adapter.count += 10;
					adapter.notifyDataSetChanged();

				}else{
					listView.removeFooterView(loadingLayout); 
				}
			}
		});
		
		//得到一个ListView用来显示条目
		listView = getListView();
		//添加到脚页显示
		listView.addFooterView(loadingLayout);
		//给ListView添加适配器
		setListAdapter(adapter);
		//给ListView注册滚动监听
		listView.setOnScrollListener(this);
	}
	@Override
	public void onScroll(AbsListView v, int firstVisibleItem,
			int visibleItemCount, int totalItemCount) {
		Log.i(TAG , "Scroll>>>first: " + firstVisibleItem + ", visible: " + visibleItemCount + ", total: " + totalItemCount);
		lastItem = firstVisibleItem + visibleItemCount - 1;
		Log.i(TAG , "Scroll>>>lastItem:" + lastItem);
		//显示50条ListItem，即0-49，因为onScroll是在“滑动”执行过之后才触发，所以用adapter.count<=41作条件
		/*if (adapter.count<=41) {
			if (firstVisibleItem+visibleItemCount==totalItemCount) {
				adapter.count += 10;
				adapter.notifyDataSetChanged();
				listView.setSelection(lastItem);
				int currentPage=adapter.count/10;
				Toast.makeText(getApplicationContext(), "第"+currentPage+"页", Toast.LENGTH_LONG).show();
			}
		}
		else {
			 listView.removeFooterView(loadingLayout); 
		}
		*/

		
	}
	@Override
	public void onScrollStateChanged(AbsListView v, int state) {
		if (lastItem == adapter.count && state == OnScrollListener.SCROLL_STATE_IDLE) {
		/*	Log.i(TAG,"ScrollStateChanged>>>state:"+state+"lastItem:" + lastItem);
			//显示50条ListItem，即0-49，因为onScrollStateChanged是在“拖动滑动”执行过之后才触发，所以用adapter.count<=41作条件
			if (adapter.count<=41) {
				adapter.count += 10;
				adapter.notifyDataSetChanged();

			}else{
				listView.removeFooterView(loadingLayout); 
			}
*/

		}
	}
  /**
   * 要用用于生成显示数据
   * @author huangbq
   *
   */
	class listViewAdapter extends BaseAdapter {
		int count = 10;

		public int getCount() {
			Log.i(TAG, "getCount>>>count:" + count);
			return count;
		}

		public Object getItem(int pos) {
			Log.i(TAG, "getItem>>>pos:" + pos);
			return pos;
		}

		public long getItemId(int pos) {
			Log.i(TAG, "getItemId>>>ItemId:" + pos);
			return pos;
		}

		public View getView(int pos, View v, ViewGroup p) {
			Log.i(TAG, "getView>>>pos:" + pos);
			TextView view;
			if (v==null) {
				view = new TextView(MainActivity.this);
			}
			else {
				view=(TextView)v;
			}
			view.setText("ListItem " + pos);
			view.setTextSize(20f);
			view.setGravity(Gravity.CENTER);
			view.setHeight(60);
			return view;
		}
	}
}

[3] listView 不同ltem展示不同的数据

来源: 互联网发布时间: 2014-02-18

listView 不同ltem显示不同的数据

请下载附件