本文实例为大家分享了Listvie简单实现购物车的具体代码，供大家参考，具体内容如下
1.自定义view实现加减
代码语言：javascript复制public class MyView extends LinearLayout implements View.OnClickListener {
private OnAmountChangeListener mListener;
private int count;
private TextView numText;
public MyView(Context context) {
this(context,null);
}
public MyView(Context context, @Nullable AttributeSet attrs) {
this(context, attrs,0);
}
public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
View view = View.inflate(context, R.layout.add, this);
initView(view);
}
public void setText(int num){
numText.setText("" num);
}
public int getText(){
getTextString();
return count;
}
private void initView(View view) {
Button addBtn = view.findViewById(R.id.btn_add);
Button jianBtn = view.findViewById(R.id.btn_jian);
numText = view.findViewById(R.id.txt_num);
getTextString();
addBtn.setOnClickListener(this);
jianBtn.setOnClickListener(this);
}
public void setOnclickNum(OnAmountChangeListener mListener){
this.mListener = mListener;
}
@Override
public void onClick(View view) {
getTextString();
switch (view.getId()){
case R.id.btn_add:
count ;
break;
case R.id.btn_jian:
if(count 0){
count--;
}
break;
}
numText.setText("" count);
if(mListener!=null) {
mListener.onAmountChange(view, count);
}
}
public void getTextString() {
String numStr = numText.getText().toString().trim();
count = Integer.parseInt(numStr);
}
public interface OnAmountChangeListener {
void onAmountChange(View view, int amount);
}
}2.适配器接口回调
代码语言：javascript复制public class MyAdapter extends BaseAdapter {
private List<Text mList;
private Context context ;
private GaroupClick garoupClick;
private int index;
private CountClick countClick;
public MyAdapter(Context context) {
this.context = context;
}
@Override
public int getCount() {
return mList.size();
}
public void setData(List<Text mList){
this.mList = mList;
notifyDataSetChanged();
}
@Override
public Object getItem(int i) {
return mList.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
public void setOnCountClick(CountClick click){
this.countClick = click;
}
public void setOnGroupclick(GaroupClick groupclick){
this.garoupClick = groupclick;
}
@Override
public View getView(final int i, View view, ViewGroup viewGroup) {
final ViewHolder holder ;
if(view==null){
holder = new ViewHolder();
view = View.inflate(context, R.layout.item, null);
holder.childCheck = view.findViewById(R.id.cb_chid_checked);
holder.txtPrice = view.findViewById(R.id.txt_price);
holder.myView = view.findViewById(R.id.myview);
view.setTag(holder);
}else{
holder = (ViewHolder)view.getTag();
}
final Text text = mList. get(i);
holder.childCheck.setChecked(text.isChoose());
holder.txtPrice.setText("" text.getPrice());
holder.myView.setText(text.getCount());
holder.myView.setOnclickNum(new MyView.OnAmountChangeListener() {
@Override
public void onAmountChange(View view, int amount) {
text.setCount(amount);
}
});
boolean checked = holder.childCheck.isChecked();
if(checked){
holder.myView.setOnclickNum(new MyView.OnAmountChangeListener() {
@Override
public void onAmountChange(View view, int amount) {
if(countClick!=null){
countClick.onNumClick(i,amount);
}
}
});
}
holder.childCheck.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
text.setChoose(((CheckBox)view).isChecked());
if(garoupClick!=null){
garoupClick.onItemClick(i,((CheckBox)view).isChecked());
}
}
});
return view;
}
class ViewHolder{
CheckBox childCheck;
TextView txtPrice;
MyView myView;
}
public interface GaroupClick{
void onItemClick(int position, boolean isChoose);
}
public interface CountClick{
void onNumClick(int position, int count);
}
}3.调用
代码语言：javascript复制public class MainActivity extends AppCompatActivity implements MyAdapter.GaroupClick, MyAdapter.CountClick {
private Button jiesuanBtn;
private ListView mListView;
private CheckBox allCheck;
private TextView priceText;
private List<Text mList = new ArrayList< ();
private int numPrice = 0;
private int count = 0;
private MyAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
initData();
}
private void initData() {
for (int i = 0; i < 30; i ) {
Text txt = new Text();
txt.setPrice(20);
txt.setCount(1);
mList.add(txt);
}
adapter = new MyAdapter(this);
adapter.setData(mList);
mListView.setAdapter(adapter);
adapter.setOnGroupclick(this);
adapter.setOnCountClick(this);
}
public boolean isAllChecked(){
for (Text text : mList) {
if(!text.isChoose()){//遍历集合，有一个不选return false
return false;
}
}
return true;
}
private void initView() {
jiesuanBtn = (Button) findViewById(R.id.btn_num);
mListView = (ListView) findViewById(R.id.listview);
allCheck = (CheckBox) findViewById(R.id.cb_all_checked);
priceText = (TextView) findViewById(R.id.txt_price_sum);
allCheck.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if(mList.size()!=0) {
if(allCheck.isChecked()) {
for (int i = 0; i < mList.size(); i ) {
mList.get(i).setChoose(true);
adapter.notifyDataSetChanged();
}
}else{
for (int i = 0; i < mList.size(); i ) {
mList.get(i).setChoose(false);
adapter.notifyDataSetChanged();
}
}
upDate();
}
}
});
jiesuanBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(MainActivity.this, PayDemoActivity.class);
startActivity(intent);
}
});
}
private void upDate() {
numPrice = 0;
count = 0;
for (int i = 0; i < mList.size(); i ) {
Text text = mList.get(i);
if(text.isChoose()){
count ;
numPrice = text.getPrice()*text.getCount();
}
}
jiesuanBtn.setText("结算（" count "）");
priceText.setText("合计:" numPrice);
}
@Override
public void onItemClick(int position, boolean isChoose) {
mList.get(position).setChoose(isChoose);
if(isAllChecked()){
allCheck.setChecked(true);
}else{
allCheck.setChecked(false);
}
adapter.notifyDataSetChanged();
upDate();
}
@Override
public void onNumClick(int position, int count) {
mList.get(position).setCount(count);
adapter.notifyDataSetChanged();
upDate();
}
}以上就是本文的全部内容，希望对大家的学习有所帮助。
