• androd ListView + CheckBox 解决超出一屏无法全选的问题。


    直接上代码  主要思路是修改List<String[]>中的值。

    Activity类

     1 package com.test.listact;
    2
    3 import java.util.ArrayList;
    4 import java.util.List;
    5
    6 import android.app.Activity;
    7 import android.os.Bundle;
    8 import android.view.View;
    9 import android.widget.Button;
    10 import android.widget.ListView;
    11 import android.widget.Toast;
    12
    13 public class ListSelectAllTestActivity extends Activity {
    14
    15 private ListView mListView ;
    16 private Button selBtn,selectedBtn;
    17 private SelectAdapter myAdapter;
    18 private boolean isSelectAll = false;
    19 private List<String[]> data = null;
    20 public void onCreate(Bundle savedInstanceState) {
    21 super.onCreate(savedInstanceState);
    22 setContentView(R.layout.main);
    23
    24 mListView = (ListView)findViewById(R.id.listview);
    25
    26 data = getData();
    27
    28 myAdapter = new SelectAdapter(this,data);
    29
    30 mListView.setAdapter(myAdapter);
    31
    32 selBtn = (Button)findViewById(R.id.selBtn);
    33
    34 selBtn.setOnClickListener(new Button.OnClickListener(){
    35 public void onClick(View arg0) {
    36 if(isSelectAll){
    37 myAdapter.cancelAll();
    38 isSelectAll = false;
    39 }else{
    40 myAdapter.selectAll();
    41 isSelectAll = true;
    42 }
    43 }
    44 });
    45
    46 selectedBtn = (Button)findViewById(R.id.selectedBtn);
    47 selectedBtn.setOnClickListener(new Button.OnClickListener(){
    48 public void onClick(View arg0) {
    49 if(data!=null){
    50 String []d;
    51 int select = 0,cancel = 0;
    52 for(String [] dd:data){
    53 if(!dd[1].equals("0")){ // '0' 代表未选中
    54 select++;
    55 }else{
    56 cancel++;
    57 }
    58 }
    59 Toast.makeText(ListSelectAllTestActivity.this, "选中数:"+select +"\t未选中数:"+cancel,Toast.LENGTH_LONG).show();
    60 }
    61 }
    62 });
    63 }
    64
    65 private List<String[]> getData(){
    66 List<String[]> list = new ArrayList<String[]>();
    67 for(int i = 0;i<20;i++){
    68 String [] data = new String[2];
    69 data[0] = "Hello" + (i+1);
    70 data[1] = "0";
    71 list.add(data);
    72 }
    73 return list;
    74 }
    75
    76 }

    Adapter 类,主要逻辑在这里

    package com.test.listact;

    import java.util.List;

    import android.content.Context;
    import android.util.Log;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.CheckBox;
    import android.widget.CompoundButton;
    import android.widget.TextView;

    public class SelectAdapter extends BaseAdapter {


    private LayoutInflater mInflater;
    private Context mContext;
    private List <String[]> mList;

    public SelectAdapter(Context mContext,List <String[]> mlist){
    this.mList = mlist;
    this.mContext = mContext;
    this.mInflater = LayoutInflater.from(mContext);
    }

    public int getCount() {
    return mList.size();
    }

    public Object getItem(int arg0) {
    return mList.get(arg0);
    }

    public long getItemId(int arg0) {
    return arg0;
    }

    public View getView(int position, View view, ViewGroup parent) {
    ViewHold mViewHold;
    if(view == null){
    Log.d("","View VVVVV");
    mViewHold = new ViewHold();
    view = mInflater.inflate(R.layout.item,null);
    mViewHold.mTextView = (TextView)view.findViewById(R.id.label);
    mViewHold.mCheckBox = (CheckBox)view.findViewById(R.id.labelCheckBox);
    view.setTag(mViewHold);
    }else{
    mViewHold = (ViewHold)view.getTag();
    Log.d("","View VVVVVEEEEEEEEEE");
    }

    String data[] = mList.get(position);
    mViewHold.mTextView.setText(data[0]);

    String isSelected = data[1];

    mViewHold.mCheckBox.setId(position);
    mViewHold.mCheckBox.setChecked(!isSelected.equals("0"));

    //点击时把值修改下
    mViewHold.mCheckBox.setOnCheckedChangeListener(new CheckBox.OnCheckedChangeListener(){

    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

    String dat[] = mList.get(buttonView.getId());
    dat[1] = isChecked?"1":"0";
    mList.set(buttonView.getId(), dat);
    }

    });



    return view;
    }
    //全选
    public void selectAll(){
    if(mList!=null){
    for(int i=0;i<mList.size();i++){
    mList.get(i)[1] = "1";
    }
    this.notifyDataSetChanged();
    }
    }
    //取消全选
    public void cancelAll(){
    if(mList!=null){
    for(int i=0;i<mList.size();i++){
    mList.get(i)[1] = "0";
    }
    this.notifyDataSetChanged();
    }
    }


    class ViewHold {
    public TextView mTextView;
    public CheckBox mCheckBox;
    }

    }

    XML文件这里就省略了。。。

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  • 原文地址:https://www.cnblogs.com/coacaio/p/checkbox.html
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