Android：从列表视图中点击的项目计算价格。应用程序在总活动logcat中崩溃：无效的浮动：“” [英] Android: calculate price from clicked items in listview. App crashes in total activity logcat:invalid float: “”
问题描述
-8
down vote
最爱
这是一个菜鸟，所以请耐心等待。我有食品和饮料的列表视图，然后是价格，然后是一个继续按钮，它将显示订单摘要和其他活动的总金额。单击某些项目后单击继续按钮，应用程序崩溃不幸的是appname已停止。但是，当我单击继续按钮而不单击任何项目时，它会显示订单摘要的布局。因此，在传递数据时会发生错误。在logcat中我注意到第一个Invalid float：我不知道如何解决这个问题。
我尝试过：
package edu.sti.snapchit;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import java.util.StringTokenizer;
import java.lang.String;
公共类TotalsActivity扩展AppCompatActivity {
MyApp mApp;
EditText et_summary;
TextView tv_total;
Button btn_code;
@Override
public void onCreate（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）;
setContentView（R.layout.totals）;
btn_code =（Button）findViewById（R.id.btn_code）;
mApp =（（MyApp）getApplicationContext（））;
et_summary =（EditText）findViewById（R.id.et_summary）;
tv_total =（TextView）findViewById（R.id.tv_total）;
et_summary.setText（mApp.getGlobalVarValue（））;
String str = mApp.getGlobalVarValue（）;
StringTokenizer st = new StringTokenizer（str，Php）;
String test =;
浮动总数= 0;
int count = 0;
while（st.hasMoreElements（））
{
test = st.nextElement（）。toString（）。substring（0,1）;
if（count> 0）
total + = Float.parseFloat（test）;
count ++;
}
tv_total.setText（总计：+总计+）;
mApp.setGlobalClear（）;
btn_code.setOnClickListener（new View.OnClickListener（）{
@Override
public void onClick（View view）{
Intent intent = new Intent（TotalsActivity.this ，GeneratorActivity.class）;
startActivity（intent）;
}
}）;
}
public boolean isFloat（String input）
{
try
{
Float.parseFloat（输入）;
返回true;
}
catch（例外e）
{
返回false;
}
}
}
包含列表视图的食物活动代码
包edu.sti.snapchit;
导入android。 content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase ;
导入android.os.Bundle;
导入android.support.v7.app.AlertDialog;
导入android.support.v7。 app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
导入android.widget.Button;
导入android.widget.ListView;
导入android.widget.Toast;
import java.util.HashMap;
公共类NewFoodsActivity扩展AppCompatActivity {
MyApp mApp;
私有HashMap<字符串，位置& GT;位置;
ListView listView1;
SQLiteDatabase数据库;
@Override
protected void onCreate（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）;
db = openOrCreateDatabase （Foods_DB，Context.MODE_PRIVATE，null）;
setContentView（R.layout.new_foods）;
locations = loadLocationData（）;
addListenerButton（）;
initializeUI（）;
}
public void initializeUI（）
{
String [] foodies = getFoodNames（）;
ArrayAdapter< string> adapter = new ArrayAdapter< string>
（这个，android.R.layout.simple_list_item_1，美食家）;
listView1.setAdapter（适配器）;
}
private String [] getFoodNames（）
{
String [] foodies = new String [locations.size（）];
美食家= locations.keySet（）。toArray（美食家）;
返回美食家;
}
私人void displaySelectedFoodInfo（String foodName）
{
}
public void showMessage（String title，String message）
{
AlertDialog.Builder builder = new AlertDialog.Builder（this）;
builder.setCancelable（true）;
builder.setTitle（title）;
builder.setMessage（message）;
builder.show（）;
}
private HashMap< String，Location> loadLocationData（）
{
HashMap< String，Location> locations = new HashMap< String，Location>（） ;
光标c = db.rawQuery（SELECT * FROM table_foods order by food_id
asc，null）;
StringBuffer buffer = new StringBuffer（） ;
while（c.moveToNext（））
{
locations.put（ - + c.getString（1）.toString （）+[Php
+ c.getString（2）.toString（）+]，新位置（Integer.parseInt（c.getString（0）），c.getString（ 1）.toString（），Double.parseDouble（c.getString（2））））;
}
返回位置;
}
public void addListenerButton（）
{
final Context context = this;
Button btnAdd =（Button）findViewById（R.id.btn_add）;
Button btnProceed =（Button）findViewById（R.id.btnProceed）;
Button btn_drinks =（按钮）findViewById（R.id.btn_drinks）;
按钮btn_foods =（按钮）findViewById（R.id.btn_foods）;
listView1 =（ListView）findViewById （R.id.listView1）;
listView1.setOnI temClickListener（
new AdapterView.OnItemClickListener（）{
@Override
public void onItemClick（AdapterView<？> Arg0，View view，int
position，long id）{
Object o = listView1.getItemAtPosition（position）;
String pen = o .toString（）;
mApp =（（MyApp）getApplicationContext（））;
mApp.setGlobalVarValue（pen）;
Toast.makeText（getApplicationContext（），Item Added+
+ pen，Toast.LENGTH_LONG）.show（）;
}
}
）;
btnAdd.setOnClickListener（new View.OnClickListener （）{b / b
@Override
public void onClick（查看视图）{
意图intent = new Intent（context，NewAddFoods.class）;
startActivity（意图）;
}
}）;
btnProceed .setOnClickListener（new View.OnClickListener（）{
@Override
public void onClick（查看视图）{
意图intent = new Intent（context，TotalsActivity.class）;
startActivity（intent）;
}
}）;
btn_foods.setOnClickListener（new View.OnClickListener（）{
@Override
public void onClick（查看视图）{
意图intent = new Intent（context，NewFoodsActivity.class）;
startActivity（intent）;
}
}）;
btn_drinks.setOnClickListener（new View.OnClickListener（） {
@Override
public void onClick（查看视图）{
Intent intent = new Intent（context，NewDrinksActivity.class）;
startActivity（意图）;
}
}）;
}
}
这是LOGCAT中的彩色红色文字
02-20 04：37：23.624 1447-1447 / edu.sti.snapchit E / AndroidRuntime：FATAL EXCEPTION：main java.lang.RuntimeException：无法启动活动ComponentInfo {edu.sti .snapchit / edu.sti.snapchit.TotalsActivity}：java.lang.NumberFormatException：在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java）的android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2211）中无效的浮点数： ：2261）在Android.app.Handler.dispatchMessage（Handler.java:99）的android.app.ActivityThread.access $ 600（ActivityThread.java:141）android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1256） ）在android.app.Looper.loop（Looper.java:137）的android.app.ActivityThread.main（ActivityThread.java:5103）处于java.lang的java.lang.reflect.Method.invokeNative（Native Method）。在com.android.internal.os.ZygoteInit.main的com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:737）中反映.Method.invoke（Method.java:525）（ZygoteInit.java： 553）在dalvik.system.Native Start.main（Native Method）引起：java.lang.NumberFormatException：java.lang.StringToReal.parseFloat（StringToReal.java:289）java.lang.StringToReal.invalidReal（StringToReal.java:63）中无效的float： ）在android.app.Activity.performCreate（Activity.java:5133）的edu.sti.snapchit.TotalsActivity.onCreate（TotalsActivity.java:40）上的java.lang.Float.parseFloat（Float.java：300） .app.Instrumentation.callActivityOnCreate（Instrumentation.java:1087）在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2175）
02-20 04:37 ：29.372 1494-1494 / edu.sti.snapchit E / dalvikvm：找不到类'android.graphics.drawable.RippleDrawable'，从方法android.support.v7.widget.AppCompatImageHelper.hasOverlappingRendering引用
02-20 04：37：30.592 1494-1494 / edu.sti.snapchit E / OpenGLRenderer：从GradienCache获取MAX_TEXTURE_SIZE 02-20 04：37：30.616 1494-1494 / edu.sti。 snapchit E / OpenGLRenderer：获取MAX_TEXTURE_SIZE来自Caches :: initConstraints（）
Ps。是的，我在制作此应用时遵循了一个youtube教程。在vid中的应用程序正在完美地工作，而我的崩溃。要么我错过了一些东西，但我检查了代码10次，或者是否有部分vid被跳过。上传者几天都没有回复:(
我差点忘了可能还有另外一个原因造成这种情况。在TotalsActivity中，方法isFloat从未使用过。
H.handleMessage（ActivityThread.java:1256）的h2_lin>解决方案
600（ActivityThread.java:141）。 android.app.Looper.loop（Looper.java:137）的os.Handler.dispatchMessage（Handler.java:99）位于android.app.ActivityThread.main（ActivityThread.java:5103）的java.lang.reflect.Method .invokeNative（Native Method）at java.lang.reflect.Method.invoke（Method.java:525）at com.android.internal.os.ZygoteInit
MethodAndArgsCaller.run（ZygoteInit。 java：737）at com.android.internal.os.ZygoteInit.main（ZygoteInit.java:553）at dalvik.system.NativeStart.main（Native Method）引起：java.lang.NumberFormatException：无效的浮点数：at java.lang.StringTtringRea上的java.lang.StringToReal.invalidReal（StringToReal.java:63）位于android.app.Activity.performCreate的edu.sti.snapchit.TotalsActivity.onCreate（TotalsActivity.java:40）的java.lang.Float.parseFloat（Float.java:300）中的l.parseFloat（StringToReal.java:289） （Activity.java:5133）在android.app.Instrumentation.callActivityOnCreate（Instrumentation.java:1087）android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2175）
02-20 04：37：29.372 1494-1494 / edu.sti.snapchit E / dalvikvm：找不到类'android.graphics.drawable.RippleDrawable'，从方法android.support.v7.widget.AppCompatImageHelper中引用.hasOverlappingRendering
02-20 04：37：30.592 1494-1494 / edu.sti.snapchit E / OpenGLRenderer：从GradienCache获取MAX_TEXTURE_SIZE 02-20 04:37： 30.616 1494-1494 / edu.sti.snapchit E / OpenGLRenderer：从Caches :: initConstraints获取MAX_TEXTURE_SIZE（）
Ps。是的，我在制作此应用时遵循了一个youtube教程。在vid中的应用程序正在完美地工作，而我的崩溃。要么我错过了一些东西，但我检查了代码10次，或者是否有部分vid被跳过。上传者几天都没有回复:(
我差点忘了可能还有另外一个原因造成这种情况。在TotalsActivity中，方法isFloat从未使用过。
-8 down vote favorite Im a noob in this so please bear with me. I have a listview of food and drinks with price then a proceed button which will show the order summary and total amount in other activity. After I click some items then click the proceed button, the app crash "Unfortunately appname has stopped." But when I click proceed button without clicking any items it displays the layout of the order summary. Therefore the error occurs in the passing of data. In logcat I noticed first Invalid float: "" I have no idea how to fix this.
What I have tried:
package edu.sti.snapchit;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import java.util.StringTokenizer;
import java.lang.String;
public class TotalsActivity extends AppCompatActivity{
MyApp mApp;
EditText et_summary;
TextView tv_total;
Button btn_code;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.totals);
btn_code = (Button) findViewById(R.id.btn_code);
mApp=((MyApp)getApplicationContext());
et_summary = (EditText) findViewById(R.id.et_summary);
tv_total = (TextView) findViewById(R.id.tv_total);
et_summary.setText(mApp.getGlobalVarValue());
String str = mApp.getGlobalVarValue();
StringTokenizer st = new StringTokenizer(str,"Php");
String test="";
float total=0;
int count =0;
while(st.hasMoreElements())
{
test = st.nextElement().toString().substring(0,1);
if(count>0)
total += Float.parseFloat(test);
count++;
}
tv_total.setText("Total:" + total+"");
mApp.setGlobalClear();
btn_code.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(TotalsActivity.this, GeneratorActivity.class);
startActivity(intent);
}
});
}
public boolean isFloat(String input)
{
try
{
Float.parseFloat(input);
return true;
}
catch(Exception e)
{
return false;
}
}
}
Code for Food Activity which contains the listview
package edu.sti.snapchit;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;
import java.util.HashMap;
public class NewFoodsActivity extends AppCompatActivity {
MyApp mApp;
private HashMap<String, Location> locations;
ListView listView1;
SQLiteDatabase db;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
db=openOrCreateDatabase("Foods_DB", Context.MODE_PRIVATE, null);
setContentView(R.layout.new_foods);
locations = loadLocationData();
addListenerButton();
initializeUI();
}
public void initializeUI()
{
String[] foodies = getFoodNames();
ArrayAdapter<string> adapter = new ArrayAdapter<string>
(this,android.R.layout.simple_list_item_1, foodies);
listView1.setAdapter(adapter);
}
private String[] getFoodNames()
{
String[] foodies = new String[locations.size()];
foodies = locations.keySet().toArray(foodies);
return foodies;
}
private void displaySelectedFoodInfo(String foodName)
{
}
public void showMessage(String title,String message)
{
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setCancelable(true);
builder.setTitle(title);
builder.setMessage(message);
builder.show();
}
private HashMap<String, Location>loadLocationData()
{
HashMap<String, Location>locations = new HashMap<String, Location>();
Cursor c=db.rawQuery("SELECT * FROM table_foods order by food_id
asc",null);
StringBuffer buffer = new StringBuffer();
while(c.moveToNext())
{
locations.put("- "+c.getString(1).toString()+" [Php
"+c.getString(2).toString()+"]", new Location(Integer.parseInt(c.getString(0)),c.getString(1).toString(),Double.parseDouble(c.getString(2))));
}
return locations;
}
public void addListenerButton()
{
final Context context = this;
Button btnAdd = (Button)findViewById(R.id.btn_add);
Button btnProceed = (Button)findViewById(R.id.btnProceed);
Button btn_drinks = (Button)findViewById(R.id.btn_drinks);
Button btn_foods = (Button)findViewById(R.id.btn_foods);
listView1 = (ListView) findViewById(R.id.listView1);
listView1.setOnItemClickListener(
new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> Arg0, View view, int
position, long id) {
Object o = listView1.getItemAtPosition(position);
String pen = o.toString();
mApp=((MyApp)getApplicationContext());
mApp.setGlobalVarValue(pen);
Toast.makeText(getApplicationContext(), "Item Added" +
""+ pen, Toast.LENGTH_LONG).show();
}
}
);
btnAdd.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(context, NewAddFoods.class);
startActivity(intent);
}
});
btnProceed.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(context, TotalsActivity.class);
startActivity(intent);
}
});
btn_foods.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(context, NewFoodsActivity.class);
startActivity(intent);
}
});
btn_drinks.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(context, NewDrinksActivity.class);
startActivity(intent);
}
});
}
}
This is the colored red text in LOGCAT
02-20 04:37:23.624 1447-1447/edu.sti.snapchit E/AndroidRuntime: FATAL EXCEPTION: main java.lang.RuntimeException: Unable to start activity ComponentInfo{edu.sti.snapchit/edu.sti.snapchit.TotalsActivity}: java.lang.NumberFormatException: Invalid float: "" at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261) at android.app.ActivityThread.access$600(ActivityThread.java:141) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5103) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:525) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.NumberFormatException: Invalid float: "" at java.lang.StringToReal.invalidReal(StringToReal.java:63) at java.lang.StringToReal.parseFloat(StringToReal.java:289) at java.lang.Float.parseFloat(Float.java:300) at edu.sti.snapchit.TotalsActivity.onCreate(TotalsActivity.java:40) at android.app.Activity.performCreate(Activity.java:5133) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
02-20 04:37:29.372 1494-1494/edu.sti.snapchit E/dalvikvm: Could not find class 'android.graphics.drawable.RippleDrawable', referenced from method android.support.v7.widget.AppCompatImageHelper.hasOverlappingRendering
02-20 04:37:30.592 1494-1494/edu.sti.snapchit E/OpenGLRenderer: Getting MAX_TEXTURE_SIZE from GradienCache 02-20 04:37:30.616 1494-1494/edu.sti.snapchit E/OpenGLRenderer: Getting MAX_TEXTURE_SIZE from Caches::initConstraints()
Ps. Yes I did followed a youtube tutorial in making this app. The app in vid is working perfectly while mine crashes. Either I missed something but I checked the code like 10 times or either there are parts of the vid been skipped. The uploader havent respond for days :(
I almost forgot there might also another reason that caused this. In TotalsActivity the method isFloat is never used.
600(ActivityThread.java:141) at android.app.ActivityThread
H.handleMessage(ActivityThread.java:1256) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5103) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:525) at com.android.internal.os.ZygoteInit
MethodAndArgsCaller.run(ZygoteInit.java:737) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.NumberFormatException: Invalid float: "" at java.lang.StringToReal.invalidReal(StringToReal.java:63) at java.lang.StringToReal.parseFloat(StringToReal.java:289) at java.lang.Float.parseFloat(Float.java:300) at edu.sti.snapchit.TotalsActivity.onCreate(TotalsActivity.java:40) at android.app.Activity.performCreate(Activity.java:5133) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
02-20 04:37:29.372 1494-1494/edu.sti.snapchit E/dalvikvm: Could not find class 'android.graphics.drawable.RippleDrawable', referenced from method android.support.v7.widget.AppCompatImageHelper.hasOverlappingRendering
02-20 04:37:30.592 1494-1494/edu.sti.snapchit E/OpenGLRenderer: Getting MAX_TEXTURE_SIZE from GradienCache 02-20 04:37:30.616 1494-1494/edu.sti.snapchit E/OpenGLRenderer: Getting MAX_TEXTURE_SIZE from Caches::initConstraints()
Ps. Yes I did followed a youtube tutorial in making this app. The app in vid is working perfectly while mine crashes. Either I missed something but I checked the code like 10 times or either there are parts of the vid been skipped. The uploader havent respond for days :(
I almost forgot there might also another reason that caused this. In TotalsActivity the method isFloat is never used.
这篇关于Android：从列表视图中点击的项目计算价格。应用程序在总活动logcat中崩溃：无效的浮动：“”的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
