Question

There are three problems I am facing:

1. When I click(+)button, the edit boxes are going underneath the button, whereas i want them to be displayed above.
   currently displaying:

Want like this:

 <edit text1> <edit text2>
  <edit text3> <edit text4>
  <edit text5> <edit text6>
  <edit text7> <edit text8>

  <button>      <button2>

1. As you can see, I tried parsing the edit text value which i got from the xml, into the docalc() function, and displaying the value in textbox. but its not working out. showing me nothing.
   1. can I parse values in dostuff, if yes how will i inter-relate those in docalc?

Thanks in advance…

Java Code:

import android.app.Activity;

import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.TextView;

    public class PlusbuttonActivity extends Activity 
    implements OnClickListener  {

        TextView tt;
        TextView j;
        EditText amount1;
        EditText amount2;
        double x=0;
        double y=0;
        double a=0;
        double z=0;
        double b=0;
        Button btnButton;
        /** Called when the activity is first created. */
        private LinearLayout root;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            // modified
            amount1=(EditText)findViewById(R.id.edittext1);
            amount2=(EditText)findViewById(R.id.edittext2);
            // modified 

            View btnButton =(Button) findViewById(R.id.button_next);
            Button mButton = (Button) findViewById(R.id.button);
            mButton.setGravity(Gravity.CENTER);

             tt=(TextView)findViewById(R.id.tt);
             j=(TextView)findViewById(R.id.j);

             root = (LinearLayout) findViewById(R.id.linearLayout);
             mButton.setOnClickListener(this);
        }

            @Override
            public void onClick(View v) {
              switch (v.getId()) {
                 case R.id.button:
                 View view = doStuff();
                  addViewToRoot(view);
                break;
                 case R.id.button_next:
                     View view1 = doCalc();
                     addViewToRoot(view1);
                     break;

              }
            }

          private View doCalc() {
                // TODO Auto-generated method stub
              x=Double.parseDouble(amount1.getText().toString());
              y=Double.parseDouble(amount2.getText().toString());
              z=(x*703);
              tt.setText(Double.toString(z));
              return tt;
            }

        private View doStuff() {  
                EditText t = new EditText(PlusbuttonActivity.this);
                t.setGravity(Gravity.LEFT);
                t.setWidth(250);
                EditText a = new EditText(PlusbuttonActivity.this);
                a.setGravity(Gravity.RIGHT);
                a.setWidth(250);
                LinearLayout l = new LinearLayout(PlusbuttonActivity.this);

                t.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
                // t.setBackgroundColor(0xffCECECE);


                a.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

                l.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));

                l.addView(t);
                l.addView(a); 

                return l; 


        }          

        private void addViewToRoot(View v){
          root.addView(v);
        }

    }

xml file:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
                 android:orientation="vertical"
                 android:layout_width="fill_parent"
                 android:layout_height="fill_parent"
                 android:id="@+id/linearLayout">


    <LinearLayout 
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                 >

            <TextView  
                android:layout_width="wrap_content" 
                android:layout_height="wrap_content" 
                android:gravity="left"
                android:layout_weight="1"
                android:text="Units"
                android:id="@+id/Units"
                />
            <TextView android:layout_height="wrap_content" 
            android:gravity="right" 
            android:layout_width="wrap_content" 
            android:layout_weight="1" 
            android:text="Grades"
            android:id="@+id/j"></TextView>
        </LinearLayout>
    <LinearLayout android:id="@+id/LinearLayout01" 
                      android:layout_width="wrap_content" 
                      android:layout_height="wrap_content"
                      android:orientation="horizontal">

              <EditText 
                android:layout_width="250px"     
                android:layout_height="wrap_content"    
                android:id="@+id/edittext1">
              </EditText>

              <EditText     
                android:layout_height="wrap_content"    
                android:id="@+id/edittext2" android:layout_width="150dp">
               </EditText>
        </LinearLayout>

    <LinearLayout android:id="@+id/LinearLayout01" 
                      android:layout_width="wrap_content" 
                      android:layout_height="wrap_content"
                      android:orientation="horizontal">

              <EditText 
                android:layout_width="250px"     
                android:layout_height="wrap_content"    
                android:id="@+id/edittext3">
              </EditText>

              <EditText     
                android:layout_height="wrap_content"    
                android:id="@+id/edittext4" android:layout_width="150dp">
               </EditText>
        </LinearLayout>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" >

        <Button android:layout_height="wrap_content" 
        android:gravity="center" android:id="@+id/button" android:text="+" android:layout_width="wrap_content"></Button>

    <Button
    android:id="@+id/button_next"
    android:layout_height="wrap_content"
    android:layout_width="wrap_content"
    android:layout_alignParentRight="true"
    android:text="CALCULATE"
    >
    </Button>
    </RelativeLayout>
<TextView android:text="TextView" 
android:id="@+id/tt" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content"></TextView>



    </LinearLayout>

Answer 1

First, set your LinearLayout’s id to something other than main. Like root. Main is the name of the xml file containing your layout, not the id of the LinearLayout item.

Second, Instead of using this in the constructor for the EditText, use PlusbuttonActivity.this. So change the line you use to create the EditText to this:

EditText t = new EditText(PlusbuttonActivity.this);

You have to do this because when you’re in the onClick method your technically in the OnClickListener class, and this refers to the OnClickListener object. By using PlusbuttonActivity.this you’re clarifying that you mean the PlusbuttonActivity object that you’re currently in, not the OnClickListener.

Third, to address the other issue, you can’t reference root from you anonymous OnClickListener class. Instead of calling root.addView(t), you can extract that out to a method. Putting it all together we get this:

import android.app.Activity;

import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;

public class PlusbuttonActivity extends Activity {
    /** Called when the activity is first created. */
    LinearLayout root;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

    Button mButton = (Button) findViewById(R.id.button1);
    root = (LinearLayout) findViewById(R.id.root);
    mButton.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            EditText t = new EditText(PlusbuttonActivity.this);
            t.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
            addViewToRoot(t);
        } 
    });

    }

    private void addViewToRoot(View v){
      root.addView(v);
    }
}