• ListView的CheckBox实现全部选中/不选中


    在Adapter类中定义一个HashMap列表,保存每一行是否被选中:

    private static HashMap<Integer, Boolean> isSelected;

    可见定义了名为isSelected的HashMap列表,再定义它的getter和setter方法:

        public static void setIsSelected(HashMap<Integer, Boolean> isSelected)   {  
            MyAdapter.isSelected = isSelected;  
        }
        
        public static HashMap<Integer, Boolean> getIsSelected() {  
            return isSelected;  
        }

    在Adapter类的构造方法中,将isSelected的所有初始值设置为false:

        public MyAdapter(Context context, List<String> list){
            this.context = context;
            this.list = list;        
            isSelected = new HashMap<Integer, Boolean>();
            initData();
        }
        
        private void initData() {  
            for (int i = 0; i < list.size(); i++) {  
                getIsSelected().put(i, false);  
            }  
        }

    在getView方法中,定义CheckBox的点击方法,当CheckBox选中/不选中时设置isSelected的值为true/false;同时根据isSelected的值设置CheckBox是否选中,并显示相应的图标:

            mCheckbox = (CheckBox)convertView.findViewById(R.id.chkBox);
            mCheckbox.setOnCheckedChangeListener(new OnCheckedChangeListener(){
                @Override
                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                    // TODO Auto-generated method stub
                    if (isChecked){
                        buttonView.setButtonDrawable(R.drawable.r02);
                        isSelected.put(position, true);
                    }else{
                        buttonView.setButtonDrawable(R.drawable.r01);
                        isSelected.put(position, false);
                    }
                }            
            });
            mCheckbox.setChecked(getIsSelected().get(position));
            if (getIsSelected().get(position)){
                mCheckbox.setButtonDrawable(R.drawable.r02);
            }else{
                mCheckbox.setButtonDrawable(R.drawable.r01);
            }

    在主窗体文件中,当点击列表下面的CheckBox时,调用selectAll方法将isSelected的所有值设置为true/false,同时显示相应的图标:

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            switch (v.getId()){
            case R.id.chkSelect:
                selectAll(chkSelect.isChecked());
                break;
            case R.id.btnDelete:
                break;
            default:
                break;
            }
            
        }
        private void selectAll(boolean x){
            for (int i=0; i<mList.size(); i++){
                mAdapter.getIsSelected().put(i, x);
            }
            if (chkSelect.isChecked()){
                chkSelect.setButtonDrawable(R.drawable.r02);
            }else{
                chkSelect.setButtonDrawable(R.drawable.r01);
            }
            mAdapter.notifyDataSetChanged();
        }

    完整的文件如下。

    MainActivity.java:

    package com.hzhi.mylistview;
    
    import android.support.v7.app.ActionBarActivity;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import android.os.Bundle;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.CheckBox;
    import android.widget.ListView;
    
    public class MainActivity extends ActionBarActivity implements OnClickListener{
        
        private CheckBox chkSelect;
        private Button btnDelete;
        private List<String> mList;
        private MyAdapter mAdapter;
        private ListView mListview;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            
            initView();
            initData();
            mAdapter = new MyAdapter(MainActivity.this, mList);
            mListview.setAdapter(mAdapter);
        }
        
        private void initView(){
            chkSelect = (CheckBox) findViewById(R.id.chkSelect);
            btnDelete = (Button) findViewById(R.id.btnDelete);
            mListview = (ListView) findViewById(R.id.lstView);
            
            chkSelect.setOnClickListener(this);
            btnDelete.setOnClickListener(this);
            
            chkSelect.setButtonDrawable(R.drawable.r01);
        }
        
        private void initData(){
            mList = new ArrayList<String>();
            for (int i=0; i<10; i++){
                mList.add("第" + String.valueOf(i) + "条数据");
            }
        }
        
        private void selectAll(boolean x){
            for (int i=0; i<mList.size(); i++){
                mAdapter.getIsSelected().put(i, x);
            }
            if (chkSelect.isChecked()){
                chkSelect.setButtonDrawable(R.drawable.r02);
            }else{
                chkSelect.setButtonDrawable(R.drawable.r01);
            }
            mAdapter.notifyDataSetChanged();
        }
    
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            switch (v.getId()){
            case R.id.chkSelect:
                selectAll(chkSelect.isChecked());
                break;
            case R.id.btnDelete:
                break;
            default:
                break;
            }
            
        }
    
    }

    MyAdapter.java:

    package com.hzhi.mylistview;
    
    import java.util.HashMap;
    import java.util.List;
    
    import android.content.Context;
    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;
    import android.widget.CompoundButton.OnCheckedChangeListener;
    
    public class MyAdapter extends BaseAdapter{
        
        List<String> list;
        Context context;
        private static HashMap<Integer, Boolean> isSelected;
        
        public MyAdapter(Context context, List<String> list){
            this.context = context;
            this.list = list;        
            isSelected = new HashMap<Integer, Boolean>();
            initData();
        }
        
        private void initData() {  
            for (int i = 0; i < list.size(); i++) {  
                getIsSelected().put(i, false);  
            }  
        }
    
        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return list.size();
        }
    
        @Override
        public Object getItem(int position) {
            // TODO Auto-generated method stub
            return list.get(position);
        }
    
        @Override
        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return position;
        }
    
        @Override
        public View getView(final int position, View convertView, ViewGroup parent) {
            // TODO Auto-generated method stub
            CheckBox mCheckbox;
            TextView mText;
            
            if(convertView == null){
                convertView = LayoutInflater.from(context).inflate(R.layout.listitem, null);
            }
            mCheckbox = (CheckBox)convertView.findViewById(R.id.chkBox);
            mCheckbox.setOnCheckedChangeListener(new OnCheckedChangeListener(){
                @Override
                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                    // TODO Auto-generated method stub
                    if (isChecked){
                        buttonView.setButtonDrawable(R.drawable.r02);
                        isSelected.put(position, true);
                    }else{
                        buttonView.setButtonDrawable(R.drawable.r01);
                        isSelected.put(position, false);
                    }
                }            
            });
            mCheckbox.setChecked(getIsSelected().get(position));
            if (getIsSelected().get(position)){
                mCheckbox.setButtonDrawable(R.drawable.r02);
            }else{
                mCheckbox.setButtonDrawable(R.drawable.r01);
            }
            
            mText = (TextView)convertView.findViewById(R.id.txtText);
            mText.setText(list.get(position).toString());
            
            return convertView;
        }
        
        public static void setIsSelected(HashMap<Integer, Boolean> isSelected) {  
            MyAdapter.isSelected = isSelected;  
        }
        
        public static HashMap<Integer, Boolean> getIsSelected() {  
            return isSelected;  
        }
    
    }

     运行效果如下:

    选中最下面的CheckBox后,实现全部选中:

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  • 原文地址:https://www.cnblogs.com/mstk/p/5355462.html
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