Android-从自定义Listview中删除一个项目,并在长时间单击时进行更新
在我的应用程序中,我使用的是自定义Listview,当长时间单击Listview时,我需要同时从Listview中删除一个项目以及CSV文件中相应的行 我的CSV文件如下所示 2020/11/22,晚上10:30,华氏96.3度,正常,车身 2020/11/22,晚上10:30,华氏98.2度,正常,车身 2020/11/22,晚上10:31,华氏96.7度,正常,车身 2020/11/22,晚上10:40,华氏95.0度,正常,车身 例如,如果长时间单击时删除了Listview中的第二项,则在长时间单击Listview时,也应删除CSV文件中位于CSV文件上方的第二行的相应数据行。 这是我的代码: LogViewActivity.javaAndroid-从自定义Listview中删除一个项目,并在长时间单击时进行更新,android,android-listview,Android,Android Listview,在我的应用程序中,我使用的是自定义Listview,当长时间单击Listview时,我需要同时从Listview中删除一个项目以及CSV文件中相应的行 我的CSV文件如下所示 2020/11/22,晚上10:30,华氏96.3度,正常,车身 2020/11/22,晚上10:30,华氏98.2度,正常,车身 2020/11/22,晚上10:31,华氏96.7度,正常,车身 2020/11/22,晚上10:40,华氏95.0度,正常,车身 例如,如果长时间单击时删除了Listview中的第二项,则在
public class LogViewActivity extends BaseAppCompatActivity {
private static final String TAG = "LogViewActivity";
private File logFile;
private Toolbar toolbar;
private ListView lvproducts;
ArrayList<Product> list;
ProductAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.log_view_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
finish();
}
});
}
}
public void onResume() {
super.onResume();
logFile = (File) getIntent().getExtras().get(Constants.EXTRA_LOG_FILE);
if (logFile != null) {
toolbar.setTitle(logFile.getName());
try {
setLogText(logFile);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_log_view, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
Intent intent;
switch (item.getItemId()) {
case R.id.action_send_to:
intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(logFile), "text/plain");
startActivity(intent);
break;
default:
Log.e(TAG, "Unknown id");
break;
}
return super.onOptionsItemSelected(item);
}
private void setLogText(File file) throws FileNotFoundException {
// Textview visisbility is invisible and used only for setting up String data.
TextView textView1 = (TextView) findViewById(R.id.tvview1);
TextView textView2 = (TextView) findViewById(R.id.tvview2);
TextView textView3 = (TextView) findViewById(R.id.tvview3);
TextView textView4 = (TextView) findViewById(R.id.tvview4);
TextView textView5 = (TextView) findViewById(R.id.tvview5);
lvproducts = (ListView) findViewById(R.id.lvproducts);
list =new ArrayList<Product>();
Scanner inputStream;
inputStream = new Scanner(file);
while(inputStream.hasNext()){
String line= inputStream.next();
if (line.equals("")) { continue; } // <--- notice this line
String[] values = line.split(",");
String V = values[0];
String W= values[1];
String X= values[2];
String Y= values[3];
String Z= values[4];
// Textview visisbility is invisible and used only for setting up String data.
textView1.setText(Z);
textView2.setText(X);
textView3.setText(Y);
textView4.setText(V);
textView5.setText(W);
Product product1 = new Product(textView1.getText().toString(), textView2.getText().toString(), textView3.getText().toString(), textView4.getText().toString(), textView5.getText().toString());
list.add(product1);
adapter = new ProductAdapter(LogViewActivity.this, list);
lvproducts.setAdapter(adapter);
}
inputStream.close();
lvproducts.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
int which_item = position;
new AlertDialog.Builder(LogViewActivity.this)
.setTitle(getResources().getString(R.string.delete_log_file_title))
.setMessage(getResources().getString(R.string.delete_log_file_text) + "\n"
+ getResources().getString(R.string.file_name))
.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
list.remove(which_item);
adapter.notifyDataSetChanged();
}
})
.setNegativeButton(android.R.string.cancel, null)
.show();
return true;
}
});
}
}
public class Product {
private String mode;
private String temp;
private String condition;
private String dates;
private String times;
public Product(String mode, String temp, String condition, String dates, String times) {
this.mode = mode;
this.temp = temp;
this.condition = condition;
this.dates = dates;
this.times = times;
}
public String getMode() {
return mode;
}
public String getTemp() {
return temp;
}
public String getCondition() {
return condition;
}
public String getDates() {
return dates;
}
public String getTimes() {
return times;
}
}
public class ProductAdapter extends ArrayAdapter<Product> {
private final Context context;
private final ArrayList<Product> values;
public ProductAdapter(@NonNull Context context, ArrayList<Product> list) {
super(context, R.layout.row_layout, list);
this.context = context;
this.values = list;
}
@SuppressLint("ResourceAsColor")
@NonNull
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowview = inflater.inflate(R.layout.row_layout, parent, false);
CardView cdview = (CardView) rowview.findViewById(R.id.cdview);
TextView tvtemp = (TextView) rowview.findViewById(R.id.tvtemp);
TextView tvcondition = (TextView) rowview.findViewById(R.id.tvcondition);
TextView tvdate = (TextView) rowview.findViewById(R.id.tvdate);
TextView tvtime = (TextView) rowview.findViewById(R.id.tvtime);
ImageView ivmode = (ImageView) rowview.findViewById(R.id.ivmode);
tvtemp.setText(values.get(position).getTemp());
tvcondition.setText(values.get(position).getCondition());
tvdate.setText(values.get(position).getDates());
tvtime.setText(values.get(position).getTimes());
if(values.get(position).getMode().equals("Object") && (values.get(position).getCondition().equals("None")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_blue);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.homewhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("Normal")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backgreen);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("Low-Grade-Fever")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backyellow);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("High-Fever")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backred);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("HIGH")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backred);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("LOW")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_low);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_black);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Object") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_black);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.homewhite);
}
return rowview;
}
}
ProductAdapter.java
public class LogViewActivity extends BaseAppCompatActivity {
private static final String TAG = "LogViewActivity";
private File logFile;
private Toolbar toolbar;
private ListView lvproducts;
ArrayList<Product> list;
ProductAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.log_view_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
finish();
}
});
}
}
public void onResume() {
super.onResume();
logFile = (File) getIntent().getExtras().get(Constants.EXTRA_LOG_FILE);
if (logFile != null) {
toolbar.setTitle(logFile.getName());
try {
setLogText(logFile);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_log_view, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
Intent intent;
switch (item.getItemId()) {
case R.id.action_send_to:
intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(logFile), "text/plain");
startActivity(intent);
break;
default:
Log.e(TAG, "Unknown id");
break;
}
return super.onOptionsItemSelected(item);
}
private void setLogText(File file) throws FileNotFoundException {
// Textview visisbility is invisible and used only for setting up String data.
TextView textView1 = (TextView) findViewById(R.id.tvview1);
TextView textView2 = (TextView) findViewById(R.id.tvview2);
TextView textView3 = (TextView) findViewById(R.id.tvview3);
TextView textView4 = (TextView) findViewById(R.id.tvview4);
TextView textView5 = (TextView) findViewById(R.id.tvview5);
lvproducts = (ListView) findViewById(R.id.lvproducts);
list =new ArrayList<Product>();
Scanner inputStream;
inputStream = new Scanner(file);
while(inputStream.hasNext()){
String line= inputStream.next();
if (line.equals("")) { continue; } // <--- notice this line
String[] values = line.split(",");
String V = values[0];
String W= values[1];
String X= values[2];
String Y= values[3];
String Z= values[4];
// Textview visisbility is invisible and used only for setting up String data.
textView1.setText(Z);
textView2.setText(X);
textView3.setText(Y);
textView4.setText(V);
textView5.setText(W);
Product product1 = new Product(textView1.getText().toString(), textView2.getText().toString(), textView3.getText().toString(), textView4.getText().toString(), textView5.getText().toString());
list.add(product1);
adapter = new ProductAdapter(LogViewActivity.this, list);
lvproducts.setAdapter(adapter);
}
inputStream.close();
lvproducts.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
int which_item = position;
new AlertDialog.Builder(LogViewActivity.this)
.setTitle(getResources().getString(R.string.delete_log_file_title))
.setMessage(getResources().getString(R.string.delete_log_file_text) + "\n"
+ getResources().getString(R.string.file_name))
.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
list.remove(which_item);
adapter.notifyDataSetChanged();
}
})
.setNegativeButton(android.R.string.cancel, null)
.show();
return true;
}
});
}
}
public class Product {
private String mode;
private String temp;
private String condition;
private String dates;
private String times;
public Product(String mode, String temp, String condition, String dates, String times) {
this.mode = mode;
this.temp = temp;
this.condition = condition;
this.dates = dates;
this.times = times;
}
public String getMode() {
return mode;
}
public String getTemp() {
return temp;
}
public String getCondition() {
return condition;
}
public String getDates() {
return dates;
}
public String getTimes() {
return times;
}
}
public class ProductAdapter extends ArrayAdapter<Product> {
private final Context context;
private final ArrayList<Product> values;
public ProductAdapter(@NonNull Context context, ArrayList<Product> list) {
super(context, R.layout.row_layout, list);
this.context = context;
this.values = list;
}
@SuppressLint("ResourceAsColor")
@NonNull
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowview = inflater.inflate(R.layout.row_layout, parent, false);
CardView cdview = (CardView) rowview.findViewById(R.id.cdview);
TextView tvtemp = (TextView) rowview.findViewById(R.id.tvtemp);
TextView tvcondition = (TextView) rowview.findViewById(R.id.tvcondition);
TextView tvdate = (TextView) rowview.findViewById(R.id.tvdate);
TextView tvtime = (TextView) rowview.findViewById(R.id.tvtime);
ImageView ivmode = (ImageView) rowview.findViewById(R.id.ivmode);
tvtemp.setText(values.get(position).getTemp());
tvcondition.setText(values.get(position).getCondition());
tvdate.setText(values.get(position).getDates());
tvtime.setText(values.get(position).getTimes());
if(values.get(position).getMode().equals("Object") && (values.get(position).getCondition().equals("None")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_blue);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.homewhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("Normal")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backgreen);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("Low-Grade-Fever")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backyellow);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("High-Fever")) && (!values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backred);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("HIGH")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.backred);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("LOW")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_low);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Body") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_black);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals("Object") && (values.get(position).getCondition().equals("None")) && (values.get(position).getTemp().equals("No-Data")))
{
Drawable draw8 = cdview.getResources().getDrawable(R.drawable.back_black);
cdview.setBackground(draw8);
ivmode.setImageResource(R.drawable.homewhite);
}
return rowview;
}
}
公共类ProductAdapter扩展了ArrayAdapter{
私人最终语境;
私有最终ArrayList值;
public ProductAdapter(@NonNull上下文,ArrayList列表){
super(上下文、R.layout.row\u布局、列表);
this.context=上下文;
这个值=列表;
}
@SuppressLint(“资源色”)
@非空
@凌驾
公共视图getView(int位置,@Nullable视图convertView,@NonNull视图组父级){
LayoutFlater充气器=(LayoutFlater)context.getSystemService(context.LAYOUT\u充气器\u服务);
视图行视图=充气机。充气(R.layout.row\u布局,父级,false);
CardView cdview=(CardView)rowview.findViewById(R.id.cdview);
TextView tvtemp=(TextView)rowview.findViewById(R.id.tvtemp);
TextView-tvcondition=(TextView)rowview.findViewById(R.id.tvcondition);
TextView-tvdate=(TextView)rowview.findViewById(R.id.tvdate);
TextView tvtime=(TextView)rowview.findViewById(R.id.tvtime);
ImageView ivmode=(ImageView)rowview.findViewById(R.id.ivmode);
tvtemp.setText(values.get(position.getTemp());
setText(values.get(position.getCondition());
tvdate.setText(values.get(position.getDates());
setText(values.get(position.getTimes());
if(values.get(position).getMode().equals(“Object”)&&(values.get(position).getCondition().equals(“None”)&(!values.get(position).getTemp().equals(“无数据”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.back_-blue);
cdview.立根点(图8);
设置图像资源(R.drawable.homewhite);
}
else if(values.get(position).getMode().equals(“Body”)&&(values.get(position).getCondition().equals(“Normal”)&(!values.get(position).getTemp().equals(“无数据”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.backgreen);
cdview.立根点(图8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals(“Body”)&(values.get(position).getCondition().equals(“低烧”)&(!values.get(position).getTemp().equals(“无数据”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.backyellow);
cdview.立根点(图8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position).getMode().equals(“Body”)&(values.get(position).getCondition().equals(“高烧”)&(!values.get(position).getTemp().equals(“无数据”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.backred);
cdview.立根点(图8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position.getMode().equals(“Body”)&&(values.get(position.getCondition().equals(“None”)&&(values.get(position.getTemp().equals(“HIGH”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.backred);
cdview.立根点(图8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position.getMode().equals(“Body”)&&(values.get(position.getCondition().equals(“None”)&&(values.get(position.getTemp().equals(“LOW”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.back\u low);
cdview.立根点(图8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position.getMode().equals(“Body”)&&(values.get(position.getCondition().equals(“None”)&&(values.get(position.getTemp().equals(“无数据”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.back_black);
cdview.立根点(图8);
ivmode.setImageResource(R.drawable.headwhite);
}
else if(values.get(position.getMode().equals(“Object”)&&(values.get(position.getCondition().equals(“None”)&&(values.get(position.getTemp().equals(“无数据”))
{
Drawable draw8=cdview.getResources().getDrawable(R.Drawable.back_black);
cdview.立根点(图8);
设置图像资源(R.drawable.homewhite);
}
返回行视图;
}
}
请帮帮我。谢谢大家! 您仅从加载的数据集中删除项,因此仅删除列表项。删除列表项时,您需要更新csv文件
lvproducts.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
int which_item = position;
new AlertDialog.Builder(LogViewActivity.this)
.setTitle(getResources().getString(R.string.delete_log_file_title))
.setMessage(getResources().getString(R.string.delete_log_file_text) + "\n"
+ getResources().getString(R.string.file_name))
.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
list.remove(which_item);
adapter.notifyDataSetChanged();
updateCSVFile();
}
})
.setNegativeButton(android.R.string.cancel, null)
.show();
return true;
}
});
public void updateCSVFile() {
// Write your logic her to update CSV file after item removal.
}
lvproducts.setOnItemLongClickListener(新的AdapterView.OnItemLongClickListener(){
@凌驾
公共布尔值长单击(AdapterView父项、视图、整型位置、长id){
int,其中_项=位置;
新建AlertDialog.Builder(LogViewActivity.this)
.setTitle(getResources().getString(R.string.delete_log_file_title))
.setMessage(getResources().getString(R.string.delete\u log\u file\u text)+“\n”
+getResources()。