android 35 ListView增删改差

MainActivity

package com.sxt.day05_11;

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

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import com.sxt.day05_11.entity.GeneralBean;

public class MainActivity extends Activity {
    ListView mlvGeneral;
    List<GeneralBean> mGenerals;
    GeneralAdapter mAdapter;
    private static final int ACTION_DETAILS=0;
    private static final int ACTION_ADD=1;
    private static final int ACTION_DELETE=2;
    private static final int ACTION_UPDATE=3;

    int mPosition;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initData();
        initView();
        setListener();
    }

    private void setListener() {
        mlvGeneral.setOnItemLongClickListener(new OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view,
                    final int position, long id) {
                AlertDialog.Builder builder=new AlertDialog.Builder(MainActivity.this);
                builder.setTitle("选择以下操作")
                    .setItems(new String[]{"查看详情","添加数据","删除数据","修改数据"}, new OnClickListener() {//倒的包是import android.content.DialogInterface.OnClickListener;
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            switch (which) {
                            case ACTION_DETAILS:
                                showDetails(position);//这个position在mGenerals.get(position);调用，说明position是资源总条数范围，
                                break;
                            case ACTION_ADD:
                                
                                break;
                            case ACTION_DELETE:
                                mAdapter.remove(position);//调用适配器的删除方法
                                break;
                            case ACTION_UPDATE:
                                //启动修改的Activity，并将当前的军事家对象传递过去
                                Intent intent=new Intent(MainActivity.this, UpdateActivity.class);
                                intent.putExtra("general", mGenerals.get(position));//mGenerals.get(position)的对象要实现序列化接口
                                mPosition=position;
                                startActivityForResult(intent, ACTION_UPDATE);//要求返回结果，ACTION_UPDATE是requestCode
                                break;
                            }
                        }

                        private void showDetails(int position) {
                            GeneralBean general=mGenerals.get(position);
                            AlertDialog.Builder builder=new AlertDialog.Builder(MainActivity.this);
                            builder.setTitle(general.getName())
                                .setMessage(general.getDetails())
                                .setPositiveButton("返回", null);//直接关闭，没有响应事件
                            AlertDialog dialog = builder.create();
                            dialog.show();
                        }
                    });
                    AlertDialog dialog = builder.create();
                    dialog.show();
                return true;
            }
        });
    }

    private void initView() {
        mlvGeneral=(ListView) findViewById(R.id.lvGeneral);
        mAdapter=new GeneralAdapter(mGenerals, this);
        mlvGeneral.setAdapter(mAdapter);
    }

    private void initData() {
        String[] names=getResources().getStringArray(R.array.general);
        String[] details=getResources().getStringArray(R.array.details);
        int[] resid={
                R.drawable.baiqi,R.drawable.caocao,R.drawable.chengjisihan,
                R.drawable.hanxin,R.drawable.lishimin,R.drawable.nuerhachi,
                R.drawable.sunbin,R.drawable.sunwu,R.drawable.yuefei,
                R.drawable.zhuyuanzhang
            };
        mGenerals=new ArrayList<GeneralBean>();
        for (int i = 0; i < resid.length; i++) {
            GeneralBean general=new GeneralBean(resid[i], names[i], details[i]);
            mGenerals.add(general);
        }
    }

    class GeneralAdapter extends BaseAdapter{
        List<GeneralBean> generals;
        MainActivity context;
        
        public void remove(int position){//适配器移出方法，就是移除资源总数据，
            generals.remove(position);
            notifyDataSetChanged();//BaseAdapter的方法，执行后安卓系统会调用getView()方法重新绘制，
        }
        
        public void add(GeneralBean general){
            mGenerals.add(general);
            notifyDataSetChanged();
        }
        
        public void update(int position,GeneralBean general){
            mGenerals.set(position, general);
            notifyDataSetChanged();
        }
        
        public GeneralAdapter(List<GeneralBean> generals, MainActivity context) {
            super();
            this.generals = generals;
            this.context = context;
        }

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

        @Override
        public Object getItem(int position) {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder=null;
            if(convertView==null){
                convertView=View.inflate(context, R.layout.item_general, null);
                holder=new ViewHolder();
                holder.ivThumb=(ImageView) convertView.findViewById(R.id.ivThumb);
                holder.tvName=(TextView) convertView.findViewById(R.id.tvName);
                convertView.setTag(holder);
            }else{//滚屏的时候重复利用convertView
                holder=(ViewHolder) convertView.getTag();
            }
            GeneralBean general=generals.get(position);
            holder.ivThumb.setImageResource(general.getResid());
            holder.tvName.setText(general.getName());
            return convertView;
        }
        
        class ViewHolder{
            ImageView ivThumb;
            TextView tvName;
        }
    }
    
    @Override
    //处理UpdateActivity返回的结果
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if(resultCode!=RESULT_OK){//判断resultCode
            return ;
        }
        switch (requestCode) {//判断requestCode
        case ACTION_UPDATE:
            GeneralBean general=(GeneralBean) data.getSerializableExtra("general");//获取修改完以后的对象
            mAdapter.update(mPosition, general);//调用适配器的更新方法，mPosition是修改的对象在集合的索引
            break;
        case ACTION_ADD:
            
            break;
        }
    }
}

mainactivity页面：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ListView
        android:id="@+id/lvGeneral"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</RelativeLayout>

修改Activity：

package com.sxt.day05_11;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.EditText;
import android.widget.ImageView;

import com.sxt.day05_11.entity.GeneralBean;

public class UpdateActivity extends Activity {
    //要修改对象的名字（控件显示），详细信息（控件显示），
    EditText metName,metDetails;
    ImageView mivThumb;//图片
    int mPhotoId;//图片id
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_update);
        initView();
        initData();
        setListener();
    }

    private void setListener() {
        setOKClickListtener();
        setCancelClickListener();
    }

    private void setCancelClickListener() {
        findViewById(R.id.btnCancel).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                finish();
            }
        });
    }

    private void setOKClickListtener() {
        findViewById(R.id.btnOK).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                String details=metDetails.getText().toString();
                String name=metName.getText().toString();
                //不能根据图片控件获取图片的id，所以多用一个变量保存图片的id
                GeneralBean general=new GeneralBean(mPhotoId, name, details);
                Intent intent=new Intent(UpdateActivity.this, MainActivity.class);
                intent.putExtra("general", general);
                setResult(RESULT_OK, intent);//RESULT_OK是resultCode结果码
                finish();//关闭当前页面
            }
        });
    }

    //接收数据
    private void initData() {
        Intent intent = getIntent();
        GeneralBean general=(GeneralBean) intent.getSerializableExtra("general");
        //数据显示在控件里面
        metDetails.setText(general.getDetails());
        metName.setText(general.getName());
        mivThumb.setImageResource(general.getResid());//图片是根据id获取的
        mPhotoId=general.getResid();//保存图片id
    }

    private void initView() {
        //用布局实例化对象
        metDetails=(EditText) findViewById(R.id.etDetails);
        metName=(EditText) findViewById(R.id.etName);
        mivThumb=(ImageView) findViewById(R.id.iv_updae_thumb);
    }

}

修改Activity页面：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/iv_updae_thumb"
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:scaleType="fitXY"                   
        android:src="@drawable/baiqi"/>
    <EditText                                           可编辑的输入框
        android:id="@+id/etName"
        android:layout_below="@id/iv_updae_thumb"
        android:layout_width="80dp"
        android:layout_height="wrap_content"
        android:text="白起"/>
    <EditText 
        android:id="@+id/etDetails"
        android:layout_width="match_parent"
        android:layout_height="110dp"
        android:text="@string/detail"
        android:layout_toRightOf="@id/iv_updae_thumb"/>
    
    <Button 
        android:id="@+id/btnOK"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="修改"
        android:layout_below="@id/etDetails"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="20dp"/>
    <Button 
        android:id="@+id/btnCancel"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="放弃"
        android:layout_below="@id/etDetails"
        android:layout_marginTop="20dp"
        android:layout_toRightOf="@id/btnOK"
        android:layout_marginLeft="50dp"/>
    
</RelativeLayout>

item_general.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" >         横向
    
    <ImageView 
        android:id="@+id/ivThumb"
        android:layout_width="60dp"
        android:layout_height="60dp"
        android:scaleType="fitXY"                  自动缩放
        android:src="@drawable/baiqi"/>

    <TextView 
        android:id="@+id/tvName"
        android:layout_width="wrap_content"
        android:layout_height="60dp"
        android:gravity="center_vertical"        内部垂直居中
        android:textSize="20sp"
        android:text="白起"
        android:layout_marginLeft="10dp"/>    
</LinearLayout>