Android Studio skapa en enkel miniräknare
Jag har en uppgift där jag ska skapa en enkel miniräknare som bara ska bestå av två textinput-fält ett resultat-fält och fem st knappar (+,-,*,/, clear) Jag har fått till layouten som det var beskrivet men själva funktionen får jag inte till. Jag har försökt att börja med additionen men det tar stopp direkt, vad gör jag för fel?
MainActivity.java
import android.content.Intent;
import android.renderscript.Double2;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button_about = (Button) findViewById(R.id.button_about);
button_about.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Toast toast = Toast.makeText(MainActivity.this, "This is my calculator", Toast.LENGTH_LONG);
toast.show();
}
});
Button button_start_calculator = (Button) findViewById(R.id.button_start_calculator);
button_start_calculator.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(MainActivity.this, CalculatorActivity.class);
startActivity(intent);
}
});
Button button1 = (Button) findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
double result = 0;
EditText editText1 = (EditText) findViewById(R.id.input_textfield1);
EditText editText2 = (EditText) findViewById(R.id.input_textfield2);
TextView result_output = (TextView) findViewById(R.id.result);
double input1 = Double.parseDouble(editText1.getText().toString());
double input2 = Double.parseDouble(editText2.getText().toString());
result = input1 + input2;
result_output.setText(input1+input2);
}
});
xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".CalculatorActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:gravity="center">
<EditText
android:gravity="center"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:id="@+id/input_textfield1"
android:text="Input 1"
/>
<EditText
android:gravity="center"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:id="@+id/input_textfield2"
android:text="Input 2"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center">
<TextView
android:layout_width="300dp"
android:layout_height="50dp"
android:id="@+id/result"
android:text="@string/result"
android:gravity="center"
/>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
<Button
android:layout_width="75dp"
android:layout_height="wrap_content"
android:text="@string/button_addition"
android:id="@+id/button1" />
<Button
android:layout_width="75dp"
android:layout_height="wrap_content"
android:text="@string/button_subtraction"
android:id="@+id/button2" />
<Button
android:layout_width="75dp"
android:layout_height="wrap_content"
android:text="@string/button_multiplication"
android:id="@+id/button3" />
<Button
android:layout_width="75dp"
android:layout_height="wrap_content"
android:text="@string/button_divide"
android:id="@+id/button4" />
<Button
android:layout_width="75dp"
android:layout_height="wrap_content"
android:text="@string/button_clear"
android:id="@+id/button5" />
</LinearLayout>
</LinearLayout>
