2015/8/25问题集

pager页面加载顺序问题

ViewPager页面加载时要先把Pager加载进来，然后才能加载里面的控件

pager先加载进来的layout

用pager加载的页面，只预先加载了一个页面。
而其他页面的控件并没有加载进来，这就导致了null指针异常。

解决办法：在前面先加上一个view名称。

ll= (LinearLayout) myView.findViewById(R.id.ll);

listview绑定adapter

这回竟然是因为忘记吧List NEW出来了

package com.zsz.develop.wisdomcommunity.my;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import com.zsz.develop.wisdomcommunity.R;

import java.util.ArrayList;
import java.util.List;

public class MyHomeActivity extends AppCompatActivity {

private ListView lvMyHome;
private MyHomeAdapter adapter;
private List<MyHomeData> myHomeLists;
private MyHomeData myHomeData;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_my_home);
    lvMyHome= (ListView) findViewById(R.id.lvMyHome);
    lvMyHome=new ListView(this);
    myHomeLists=new ArrayList<>();
    for (int i=0;i<5;i++){
        myHomeData=new MyHomeData(i+" 父子","天大地大","审核中");

        myHomeLists.add(myHomeData);

    }

    adapter=new MyHomeAdapter(MyHomeActivity.this,myHomeLists);
    lvMyHome.setAdapter(adapter);

    setContentView(lvMyHome);
}


}

listview绑定adapter之感悟

首先在这里面的设置：

• 1.首先需要准备的数据listview承载数据，Adapter适配数据，data是数据。还需要一个装data的list集合
• 找到listview并实例化。（并不需要实例化）
• 实例化list和data，并把data装进list中
• 把list装进adapter中
• 绑定adapter
• setContentView(lvMyHome)；（错误：这也重新覆盖掉了布局）

-
更改后的代码

package com.zsz.develop.wisdomcommunity.myOneLine;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Window;
import android.widget.ListView;

import com.zsz.develop.wisdomcommunity.R;

import java.util.ArrayList;
import java.util.List;

public class MyBillctivity extends AppCompatActivity {

private List<MyBillData> myBillDataList;
private MyBillAdapter adapter;
private ListView lvMyBill;
private MyBillData myBillData;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_my_bill);
    lvMyBill= (ListView) findViewById(R.id.lvMyBill);
//不要        lvMyBill=new ListView(this);
    myBillDataList=new ArrayList<>();
    for (int i=1;i<5;i++){
        myBillData=new MyBillData("2015-1-1至2015-1-31","未交","35"+i);
        myBillDataList.add(myBillData);
    }
    adapter=new MyBillAdapter(this,myBillDataList);
    lvMyBill.setAdapter(adapter);
//不要        setContentView(lvMyBill);

}


}

Adapter的操作

错误之：setTag（）这里是传入整个类。而不是字符串

package com.zsz.develop.wisdomcommunity.myOneLine;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import com.zsz.develop.wisdomcommunity.R;

import java.util.List;

/**
 * Created by shengzhong on 2015/8/25.
 */
public class MyBillAdapter extends BaseAdapter {
private Context context;
private List<MyBillData> myBillDataList;

public MyBillAdapter(Context context,List<MyBillData> myBillDataList){
    this.context=context;
    this.myBillDataList=myBillDataList;
}

@Override
public int getCount() {
    return myBillDataList.size();
}

@Override
public Object getItem(int i) {
    return myBillDataList.get(i);
}

@Override
public long getItemId(int i) {
    return i;
}

@Override
public View getView(int i, View view, ViewGroup viewGroup) {

    ViewHolder holder;
    if (view==null) {
        view= LayoutInflater.from(context).inflate(R.layout.my_bill_layout,null);
        holder=new ViewHolder();
        holder.tv_my_bill_layout_Time= (TextView) view.findViewById(R.id.tv_my_bill_layout_Time);
        holder.tv_my_bill_layout_CostState= (TextView) view.findViewById(R.id.tv_my_bill_layout_CostState);
        holder.tv_my_bill_layout_Cost= (TextView) view.findViewById(R.id.tv_my_bill_layout_Cost);
        holder.tv_my_bill_layout_Time.setText(myBillDataList.get(i).getTime());
        holder.tv_my_bill_layout_CostState.setText(myBillDataList.get(i).getCoatState());
        holder.tv_my_bill_layout_Cost.setText(myBillDataList.get(i).getCoat());
        view.setTag(holder);
    }else {
        holder= (ViewHolder) view.getTag();
        holder.tv_my_bill_layout_Time.setText(myBillDataList.get(i).getTime());
        holder.tv_my_bill_layout_CostState.setText(myBillDataList.get(i).getCoatState());
        holder.tv_my_bill_layout_Cost.setText(myBillDataList.get(i).getCoat());

    }

    return view;
}
private static class ViewHolder{
    TextView tv_my_bill_layout_Time;
    TextView tv_my_bill_layout_CostState;
    TextView tv_my_bill_layout_Cost;
}
}

如果要对listview的每个item添加一个点击事件操作

lvMyInterflowMain.setOnItemClickListener(new AdapterView.OnItemClickListener() {
      @Override
      public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
          Intent intent=new Intent(MyInterflowMainActivity.this,MyInterflowActivity.class);
          startActivity(intent);
      }