Reputation: 25
package kdev.circles;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText ca = (EditText)findViewById(R.id.ca);
final EditText cp = (EditText)findViewById(R.id.cp);
final EditText sv = (EditText)findViewById(R.id.sv);
final EditText r = (EditText)findViewById(R.id.radius);
final TextView log = (TextView)findViewById(R.id.log);
Button clear = (Button)findViewById(R.id.clear);
Button solve = (Button)findViewById(R.id.Solve);
clear.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
ca.setText("");
cp.setText("");
sv.setText("");
r.setText("");
}
});
solve.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if((r.toString()).equals("")) {
log.setText(log.getText() + "\n" + "error, no value entered");
}else{
sv.setText(String.valueOf(Double.valueOf(String.valueOf(r.getText())) * Double.valueOf(String.valueOf(r.getText())) * Double.valueOf(String.valueOf(r.getText())) * 4 / 3 * 3.14159265));
cp.setText(String.valueOf(Double.valueOf(String.valueOf(r.getText()))*3.14159265*2));
ca.setText(String.valueOf(Double.valueOf(String.valueOf(r.getText()))*Double.valueOf(String.valueOf(r.getText()))*3.14159265));
log.setText(log.getText()+"\n"+"ca"+ca.getText()+"\n"+"sv"+sv.getText()+"\n"+"cp"+cp.getText());
}
}
});
}
@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_main, 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);
}
}
xml file:
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Solve"
android:id="@+id/Solve"
android:width="100dp"
android:layout_alignParentBottom="true"
android:layout_alignEnd="@+id/sv" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="numberDecimal"
android:ems="10"
android:id="@+id/radius"
android:layout_alignParentTop="true"
android:layout_alignStart="@+id/editText" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="numberDecimal"
android:ems="10"
android:id="@+id/editText"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:layout_marginTop="49dp" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="numberDecimal"
android:ems="10"
android:id="@+id/editText2"
android:layout_below="@+id/editText"
android:layout_alignStart="@+id/editText" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="numberDecimal"
android:ems="10"
android:id="@+id/editText3"
android:layout_below="@+id/editText2"
android:layout_alignStart="@+id/editText2" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="circle's perimeter"
android:id="@+id/cp"
android:layout_above="@+id/editText2"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="circle's area"
android:id="@+id/ca"
android:layout_above="@+id/editText3"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="sphere's volume"
android:id="@+id/sv"
android:layout_alignBottom="@+id/editText3"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="radius"
android:id="@+id/textView3"
android:layout_alignBottom="@+id/radius"
android:layout_alignParentStart="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="clear"
android:id="@+id/clear"
android:layout_alignBottom="@+id/Solve"
android:layout_alignStart="@+id/editText3" />
<TextView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="@+id/log"
android:layout_below="@+id/editText3"
android:layout_centerHorizontal="true"
android:layout_marginTop="57dp" />
Everything is working fine till i try opening it, i couldn't find the error, because my android virtual device wasn't connected to android studio properly. I am not sure what i should do. I did have another problem before but i realised that it was due to me using the findviewbyid function before the whole layout was loaded. I have solved that problem and tried a few different techniques to solve this problem but nothing worked. When i try and run the app it just crashes, i am not sure why? Any help will be usefull, thank you. this is the logcat:
12-10 15:21:18.030 1907-1907/kdev.circles W/art﹕ Verification of java.lang.CharSequence android.support.v7.widget.ResourcesWrapper.getQuantityText(int, int) took 123.881364ms
12-10 15:21:18.520 1907-1907/kdev.circles D/AndroidRuntime﹕ Shutting down VM
12-10 15:21:18.520 1907-1907/kdev.circles E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: kdev.circles, PID: 1907
java.lang.RuntimeException: Unable to start activity ComponentInfo{kdev.circles/kdev.circles.MainActivity}: java.lang.ClassCastException: android.support.v7.widget.AppCompatTextView cannot be cast to android.widget.EditText
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
Caused by: java.lang.ClassCastException: android.support.v7.widget.AppCompatTextView cannot be cast to android.widget.EditText
at kdev.circles.MainActivity.onCreate(MainActivity.java:21)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
12-10 15:21:27.230 1907-1907/kdev.circles I/Process﹕ Sending signal. PID: 1907 SIG: 9
12-10 15:21:31.360 2153-2153/kdev.circles D/AndroidRuntime﹕ Shutting down VM
12-10 15:21:31.360 2153-2153/kdev.circles E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: kdev.circles, PID: 2153
java.lang.RuntimeException: Unable to start activity ComponentInfo{kdev.circles/kdev.circles.MainActivity}: java.lang.ClassCastException: android.support.v7.widget.AppCompatTextView cannot be cast to android.widget.EditText
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
Caused by: java.lang.ClassCastException: android.support.v7.widget.AppCompatTextView cannot be cast to android.widget.EditText
at kdev.circles.MainActivity.onCreate(MainActivity.java:21)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
Upvotes: 1
Views: 454
Reputation: 28541
Check your view types in Java code and their matching id's in xml. They have to be of same type.
You have EditText
in Java, but matching view id
in xml is TextView
For instance:
final EditText ca = (EditText)findViewById(R.id.ca);
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="circle's area"
android:id="@+id/ca"
android:layout_above="@+id/editText3"
android:layout_alignParentStart="true" />
Upvotes: 2