I'm building a simple app to calculate expenses and cost of living and provide smart living recommendations.
The app requests each expense as a textview, then when a button is clicked, it goes through the textviews, parses them as doubles and assigns them to a public value.
Here is my code:
package ericleeconklin.costoflivingcalculator;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import android.content.Context;
public class EnterExpenses extends ActionBarActivity {
public Double rentMortgage;
public Double utilities;
public Double insurance;
public Double phoneInternet;
public Double food;
public Double carPayment;
public Double miscellaneous;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_enter_expenses);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_enter_expenses, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public void enterExpenses(View view) {
try {
TextView rentView = (TextView) findViewById(R.id.enterRent);
TextView utilitiesView = (TextView) findViewById(R.id.enterUtilities);
TextView insuranceView = (TextView) findViewById(R.id.enterInsurance);
TextView phoneView = (TextView) findViewById(R.id.enterTV);
TextView foodView = (TextView) findViewById(R.id.enterFood);
TextView carView = (TextView) findViewById(R.id.enterCarPayment);
TextView miscView = (TextView) findViewById(R.id.enterMisc);
Double[] doubleExpensesArray = new Double[]{Double.parseDouble(rentView.toString()),
Double.parseDouble(utilitiesView.toString()),
Double.parseDouble(insuranceView.toString()),
Double.parseDouble(phoneView.toString()),
Double.parseDouble(foodView.toString()),
Double.parseDouble(carView.toString()),
Double.parseDouble(miscView.toString())};
rentMortgage = doubleExpensesArray[0];
utilities = doubleExpensesArray[1];
insurance = doubleExpensesArray[2];
phoneInternet = doubleExpensesArray[3];
food = doubleExpensesArray[4];
carPayment = doubleExpensesArray[5];
miscellaneous = doubleExpensesArray[6];
Intent myIntent = new Intent(this, FinalGrade.class);
startActivity(myIntent);
} catch(NullPointerException nullPointer) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Please enter valid amounts!")
.setCancelable(false)
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
//do things
}
});
AlertDialog alert = builder.create();
alert.show();
}
}
}
And my XML:
<ScrollView
android:layout_width="fill_parent"
android:id="@+id/scrollView"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Enter Your Monthly Expenses (USD)"
android:id="@+id/textView"
android:layout_marginTop="20dp"
android:layout_centerHorizontal="true"
android:textAlignment="center"/>
<EditText android:id="@+id/enterRent"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="100dp"
android:layout_centerHorizontal="true"
android:ellipsize="end"
android:singleLine="true"
android:textColorHint="#888888"
android:hint="Enter Rent/Mortgage">
</EditText>
<EditText android:id="@+id/enterUtilities"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="160dp"
android:layout_centerHorizontal="true"
android:inputType="number"
android:textColorHint="#888888"
android:hint="Enter Utilities">
</EditText>
<EditText android:id="@+id/enterInsurance"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="220dp"
android:layout_centerHorizontal="true"
android:inputType="number"
android:textColorHint="#888888"
android:hint="Enter Insurance">
</EditText>
<EditText android:id="@+id/enterTV"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="280dp"
android:layout_centerHorizontal="true"
android:inputType="number"
android:textColorHint="#888888"
android:hint="Enter TV/Phone/Internet">
</EditText>
<EditText android:id="@+id/enterFood"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="340dp"
android:layout_centerHorizontal="true"
android:inputType="number"
android:textColorHint="#888888"
android:hint="Enter Food">
</EditText>
<EditText android:id="@+id/enterCarPayment"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="400dp"
android:layout_centerHorizontal="true"
android:inputType="number"
android:textColorHint="#888888"
android:hint="Enter Car Payment">
</EditText>
<EditText android:id="@+id/enterMisc"
android:layout_width="210dp"
android:layout_height="wrap_content"
android:padding="3dip"
android:layout_marginTop="460dp"
android:layout_centerHorizontal="true"
android:inputType="number"
android:textColorHint="#888888"
android:hint="Enter Miscellaneous">
</EditText>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Grade My Cost of Living"
android:id="@+id/enterExpenses"
android:layout_marginTop="520dp"
android:layout_centerHorizontal="true"
android:onClick="enterExpenses"/>
</RelativeLayout>
</ScrollView>
答案 0 :(得分：2)
First, your XML shows only 1 TextView and the rest are EditTexts, So in your activity code will need to reflect the right object type for the id's your finding on the view.
EditText rentView = (EditText) findViewById(R.id.enterRent);
EditText utilitiesView = (EditText) findViewById(R.id.enterUtilities);
EditText insuranceView = (EditText) findViewById(R.id.enterInsurance);
EditText phoneView = (EditText) findViewById(R.id.enterTV);
EditText foodView = (EditText) findViewById(R.id.enterFood);
EditText carView = (EditText) findViewById(R.id.enterCarPayment);
EditText miscView = (EditText) findViewById(R.id.enterMisc);
Second, you must use getText().toString() on the EditTexts in order to get the text value from them. See the documentation on EditText.
Double value = Double.parseDouble(carView.getText().toString());
Then if you wanting to send this your Double[] over an Intent to the Final activity, you would do it like this.
Intent intent = new Intent(EnterExpenses.this, FinalGrade.class);
Bundle bundle = new Bundle();
bundle.putDoubleArray("your_double_key", doubleExpensesArray);
intent.putExtras(bundle);
startActivity(intent);
and would receive the double in the "FinalGrade.class" like so:
Bundle bundle = this.getIntent().getExtras();
Double[] double = bundle.getDoubleArray("your_double_key");
* You could try this *
I'd also personally set up my Button click listeners in my activity code like such instead of in XML android:onClick=""/>. This might help your issue.
Button calculate = (Button) findViewById(R.id.button).
calculate.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick() {
enterExpenses();
}
});
答案 1 :(得分：1)
you are wrong in these lines
double[] doubleExpensesArray = new double[]{Double.parseDouble(rentView**.getText().**toString()),
Double.parseDouble(utilitiesView.**.getText().**toString()),
Double.parseDouble(insuranceView.**.getText().**toString()),
Double.parseDouble(phoneView.**.getText().**toString()),
Double.parseDouble(foodView.**.getText().**toString()),
Double.parseDouble(carView.**.getText().**toString()),
Double.parseDouble(miscView.**.getText().**toString())};
答案 2 :(得分：0)
You should first get the text of the TextView before parsing all the doubles
Double.parseDouble(utilitiesView.toString()), // that's wrong
Double.parseDouble(utilitiesView.getText().toString()), // that's right
and so on to all the TextViews.