Friday, 27 November 2009

Display a marker on MapView, using Overlays.

Expends from last exercise, AndroidMapper. A marker is shown on the current location using Overlays, if MapView started with location, Mode 1.



To use Overlays, a class of InterestingLocations have to be created, extends ItemizedOverlay.

It involve modification on AndroidMapView.java

package com.AndroidMapper;

import java.util.ArrayList;
import java.util.List;

import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.view.View;
import android.widget.CheckBox;
import android.widget.TextView;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.ItemizedOverlay;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.OverlayItem;

public class AndroidMapView extends MapActivity {

private TextView myLongitude, myLatitude;
private CheckBox mySatellite;

private MapView myMapView;
private MapController myMapController;

private void SetSatellite()
{
myMapView.setSatellite(mySatellite.isChecked());
};

@Override
protected void onCreate(Bundle icicle) {
// TODO Auto-generated method stub
super.onCreate(icicle);
setContentView(R.layout.mymapview);

Bundle bundle = this.getIntent().getExtras();
int Mode = bundle.getInt("Mode");

myMapView = (MapView)findViewById(R.id.mapview);
myMapController = myMapView.getController();
myMapView.setBuiltInZoomControls(true);

myLongitude = (TextView)findViewById(R.id.longitude);
myLatitude = (TextView)findViewById(R.id.latitude);
mySatellite = (CheckBox)findViewById(R.id.satellite);
mySatellite.setOnClickListener(mySatelliteOnClickListener);

SetSatellite();


if(Mode == 1)
{
int intLatitude = bundle.getInt("Latitude");
int intLongitude = bundle.getInt("Longitude");
GeoPoint initGeoPoint = new GeoPoint(intLatitude, intLongitude);
CenterLocation(initGeoPoint);

Drawable marker=getResources().getDrawable(
android.R.drawable.ic_menu_myplaces);
marker.setBounds(0, 0, marker.getIntrinsicWidth(),
marker.getIntrinsicHeight());
myMapView.getOverlays().add(new InterestingLocations(marker,
intLatitude, intLongitude));
}
}

@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}

private void CenterLocation(GeoPoint centerGeoPoint)
{
myMapController.animateTo(centerGeoPoint);

myLongitude.setText("Longitude: "+
String.valueOf((float)centerGeoPoint.getLongitudeE6()/1000000)
);
myLatitude.setText("Latitude: "+
String.valueOf((float)centerGeoPoint.getLatitudeE6()/1000000)
);
};

private CheckBox.OnClickListener mySatelliteOnClickListener =
new CheckBox.OnClickListener(){

public void onClick(View v) {
// TODO Auto-generated method stub
SetSatellite();
}
};

class InterestingLocations extends ItemizedOverlay<OverlayItem>{

private List<OverlayItem> locations =
new ArrayList<OverlayItem>();
private Drawable marker;

public InterestingLocations(Drawable defaultMarker,
int LatitudeE6, int LongitudeE6) {
super(defaultMarker);
// TODO Auto-generated constructor stub
this.marker=defaultMarker;
// create locations of interest
GeoPoint myPlace = new GeoPoint(LatitudeE6,LongitudeE6);
locations.add(new OverlayItem(myPlace ,
"My Place", "My Place"));
populate();
}

@Override
protected OverlayItem createItem(int i) {
// TODO Auto-generated method stub
return locations.get(i);
}

@Override
public int size() {
// TODO Auto-generated method stub
return locations.size();
}

@Override
public void draw(Canvas canvas, MapView mapView,
boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);

boundCenterBottom(marker);
}
}
}



Download the files.

Adding ls and ll to Windows



When I set up a new windows machine, one of the first things I do is setup a simple alias for Unix ls command and the ll alias I usually have setup for ls -l. You don't have to install any special software. Just create two very simple batch files.



Here are the two files I typically create in the Windows directory. If running Windows 7, you will need to run your editor or command prompt as administrator to create the files.



ls.bat

dir %1 %2 %3 %4 %5



ll.bat

dir /w %1 %2 %3 %4 %5



The extra variables allow you to add extra command line parameters or pass a directory path. Not fancy, but it gets the job done. And, I don't have to think when I need a directory listing.

Thursday, 26 November 2009

Apache, MySQL and PHP for Windows 7 Starter



Windows 7 starter edition is pretty bare bones. So when I decided I wanted to look into doing some limited web development on my netbook, I needed to install something very small.  After Googling around a bit I found this server: http://www.uniformserver.com/



The Uniform Server is a Windows, Apache, MySQL, PHP bundle for Windows designed to work off flash drives. The whole package zips into a file that is only 10 megs. In addition, all the software runs from the directory the software is unzipped into. No registry changes needed. Just run the start.exe program and everything runs. Very cool.

Chrome OS

Google Logo

After launching the Go programming language, Google followed up with the announcement of their Chrome operating system. I know I am a week or two late on this post, but I have been busy. :) Basically, Chrome OS is a Linux distro optimized to be Net connected. The early target hardware appears to be Netbooks. Here are some links to details.

An OS that is basically just a browser is an interesting idea. With the way things are moving to the Net, I suppose you will be able to find everything you need online. And of course, Google wants to promote their online office apps. But I think I would still want a full featured OS. The computer biz will be interesting the next 5 years.

Monday, 23 November 2009

Exercise AndroidMapper, Android Application using MapView

In the previous exercises, the MapView track the GPS and center on it repeatly. In this exercise, AndroidMapper, it will not track on GPS. Instead, there are three options to center in starting of the MapView.
- Default: Start ViewMap without any center location.
- GPS: It's the current GPS (which will be track before ViewMap start). If no valid GPS, this option will be disable.
- Location: User input location. If no location input, this option will be disable.



After ViewMap loaded, user can move the Map, Zoom-in/out using MapView's BuiltInZoomControls.



This application is not yet finished, more feature (or bug fixed) will be added in the furture.

Create a Android Application named, AndroidMapper.
Package Name: com.AndroidMapper
Target Google Platform 2.0 with Google APIs.

Modify main.xml to have the UI as seen in the picture.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<RadioGroup
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RadioButton
android:id="@+id/option_default"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Default Location" />
<RadioButton
android:id="@+id/option_gps"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="GPS:" />
<RadioButton
android:id="@+id/option_location"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Location:" />
</RadioGroup>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="latitude"
/>
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/latitude"
android:inputType="numberDecimal"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="longitude"
/>
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/longitude"
android:inputType="numberDecimal"
/>
<Button
android:id="@+id/loadmap"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Load Map"
/>
</LinearLayout>


Modify AndroidMapper.java
package com.AndroidMapper;

import com.google.android.maps.GeoPoint;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioButton;

public class AndroidMapper extends Activity {

private LocationManager myLocationManager;
private LocationListener myLocationListener;
private GeoPoint GeoPoint_GPS, GeoPoint_Location;

RadioButton myoption_default, myoption_gps, myoption_location;
EditText mylatitude, mylongitude;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

loadMenu();
validGPS();
validLocation();

myLocationManager = (LocationManager)getSystemService(
Context.LOCATION_SERVICE);

myLocationListener = new MyLocationListener();

myLocationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
0,
0,
myLocationListener);
}

private void loadMenu()
{
setContentView(R.layout.main);
myoption_default = (RadioButton)findViewById(R.id.option_default);
myoption_gps = (RadioButton)findViewById(R.id.option_gps);
myoption_location = (RadioButton)findViewById(R.id.option_location);
mylatitude = (EditText)findViewById(R.id.latitude);
mylongitude = (EditText)findViewById(R.id.longitude);

mylatitude.setOnKeyListener(locationOnKeyListener);
mylongitude.setOnKeyListener(locationOnKeyListener);

Button myLoadMapButton = (Button)findViewById(R.id.loadmap);
myLoadMapButton.setOnClickListener(myLoadMapButtonOnClickListener);
}

Button.OnClickListener myLoadMapButtonOnClickListener =
new Button.OnClickListener(){

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(myoption_default.isChecked()){
OpenIntentAndroidMapView(null);
}
else if(myoption_gps.isChecked()){
OpenIntentAndroidMapView(GeoPoint_GPS);
}
else if(myoption_location.isChecked()){
OpenIntentAndroidMapView(GeoPoint_Location);
}
else{
OpenMissingOptionDialog();
}

}

};

private void OpenIntentAndroidMapView(GeoPoint startLocation)
{
Intent intent = new Intent();
intent.setClass(AndroidMapper.this, AndroidMapView.class);

Bundle bundle = new Bundle();

if (startLocation == null)
{
bundle.putInt("Mode", 0);
}
else
{
bundle.putInt("Mode", 1);
bundle.putInt("Longitude", startLocation.getLongitudeE6());
bundle.putInt("Latitude", startLocation.getLatitudeE6());
}

intent.putExtras(bundle);
startActivityForResult(intent, 0);
}

private void OpenMissingOptionDialog()
{
new AlertDialog.Builder(this)
.setTitle("missing selection")
.setMessage("Please select one of the option")
.setPositiveButton("OK",
new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialoginterface, int i)
{}
})
.show();
}

EditText.OnKeyListener locationOnKeyListener =
new EditText.OnKeyListener(){

@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
validLocation();
return false;
}

};

private void validGPS()
{
GeoPoint_GPS = loadGPS();
if (GeoPoint_GPS==null)
{
myoption_gps.setClickable(false);
}
else
{
myoption_gps.setText("GPS: (" +
String.valueOf((float)GeoPoint_GPS.getLatitudeE6()/1000000) +" : " +
String.valueOf((float)GeoPoint_GPS.getLongitudeE6()/1000000) +")");
myoption_gps.setClickable(true);
}
}

private void validLocation()
{
/*
Toast.makeText(AndroidMapper.this,
mylatitude.getText().toString(),
Toast.LENGTH_LONG).show();*/
if (mylatitude.getText().toString().equals("") || mylongitude.getText().toString().equals(""))
{

myoption_location.setText("Location: ");
myoption_location.setClickable(false);
myoption_location.setChecked(false);
}
else
{
float locationLatitude = Float.parseFloat(mylatitude.getText().toString());
float locationLongitude = Float.parseFloat(mylongitude.getText().toString());

myoption_location.setText("Location: (" +
String.valueOf(locationLatitude) +" : " +
String.valueOf(locationLongitude) +")");
myoption_location.setClickable(true);
myoption_location.setChecked(true);

GeoPoint_Location = new GeoPoint(
(int)(locationLatitude*1000000),
(int)(locationLongitude*1000000));
}
}

private GeoPoint loadGPS()
{
//Get the current location from GPS
myLocationManager = (LocationManager)getSystemService(
Context.LOCATION_SERVICE);
Location initLocation=myLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(initLocation != null)
{
return (
new GeoPoint(
(int)(initLocation.getLatitude()*1000000),
(int)(initLocation.getLongitude()*1000000)));
}
else
return null;
}

private class MyLocationListener implements LocationListener{

@Override
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
GeoPoint_GPS = new GeoPoint(
(int)(location.getLatitude()*1000000),
(int)(location.getLongitude()*1000000));
myoption_gps.setText("GPS: (" +
String.valueOf((float)GeoPoint_GPS.getLatitudeE6()/1000000) +" : " +
String.valueOf((float)GeoPoint_GPS.getLongitudeE6()/1000000) +")");
myoption_gps.setClickable(true);
}

@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub

}

@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub

}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub

}

}
}


Modify mymapview.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<LinearLayout
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
>
<CheckBox
android:id="@+id/satellite"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=" Satellite "
/>
</LinearLayout>
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<TextView
android:id="@+id/longitude"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Longitude:"
/>
<TextView
android:id="@+id/latitude"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Latitude:"
/>
</LinearLayout>
</LinearLayout>
<com.google.android.maps.MapView
android:id="@+id/mapview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clickable="true"
android:apiKey="-----Your Own API Key here-------------"
/>
</LinearLayout>
You have to Obtaining a Maps API Key, and insert into the field "apikey"

Modify AndroidMapView.java
package com.AndroidMapper;

import android.os.Bundle;
import android.view.View;
import android.widget.CheckBox;
import android.widget.TextView;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;

public class AndroidMapView extends MapActivity {

private TextView myLongitude, myLatitude;
private CheckBox mySatellite;

private MapView myMapView;
private MapController myMapController;

private void SetSatellite()
{
myMapView.setSatellite(mySatellite.isChecked());
};

@Override
protected void onCreate(Bundle icicle) {
// TODO Auto-generated method stub
super.onCreate(icicle);
setContentView(R.layout.mymapview);

Bundle bundle = this.getIntent().getExtras();
int Mode = bundle.getInt("Mode");

myMapView = (MapView)findViewById(R.id.mapview);
myMapController = myMapView.getController();
myMapView.setBuiltInZoomControls(true);

myLongitude = (TextView)findViewById(R.id.longitude);
myLatitude = (TextView)findViewById(R.id.latitude);
mySatellite = (CheckBox)findViewById(R.id.satellite);
mySatellite.setOnClickListener(mySatelliteOnClickListener);

SetSatellite();


if(Mode == 1)
{
int intLatitude = bundle.getInt("Latitude");
int intLongitude = bundle.getInt("Longitude");
GeoPoint initGeoPoint = new GeoPoint(intLatitude, intLongitude);
CenterLocation(initGeoPoint);
}


}



@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}

private void CenterLocation(GeoPoint centerGeoPoint)
{
myMapController.animateTo(centerGeoPoint);


myLongitude.setText("Longitude: "+
String.valueOf((float)centerGeoPoint.getLongitudeE6()/1000000)
);
myLatitude.setText("Latitude: "+
String.valueOf((float)centerGeoPoint.getLatitudeE6()/1000000)
);
};

private CheckBox.OnClickListener mySatelliteOnClickListener =
new CheckBox.OnClickListener(){

public void onClick(View v) {
// TODO Auto-generated method stub
SetSatellite();
}
};

}


Also modify AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.AndroidMapper"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".AndroidMapper"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".AndroidMapView">
</activity>
<uses-library android:name="com.google.android.maps" />
</application>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-sdk android:minSdkVersion="5" />

</manifest>


Download the files.

Sunday, 22 November 2009

Check empty of EditText



To check if the content of a EditText is empty or not, the method equals() can be used.

if (EditText.getText().toString().equals(""))
{
//Do if the EditText is empty
}
else
{
//Do if the EditText is not empty
}


Where EditText is the View of the EditText.

RadioGroup and RadioButton

In this exercise, RadioGroup and RadioButton will be described.



A radio button is a two-states button that can be either checked or unchecked. When the radio button is unchecked, the user can press or click it to check it. A radio button cannot be unchecked by the user once checked.

Radio buttons are normally used together in a RadioGroup. When several radio buttons live inside a radio group, checking one radio button unchecks all the others.

RadioGroup is used to create a multiple-exclusion scope for a set of radio buttons. Checking one radio button that belongs to a radio group unchecks any previously checked radio button within the same group.

Intially, all of the radio buttons are unchecked. While it is not possible to uncheck a particular radio button, the radio group can be cleared to remove the checked state.

main.xml with three RadioButton inside a RadioGroup.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<RadioGroup
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RadioButton
android:id="@+id/option1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Option 1" />
<RadioButton
android:id="@+id/option2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Option 2" />
<RadioButton
android:id="@+id/option3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Option 3" />
</RadioGroup>
</LinearLayout>


AndroidRadioGroup.java
package com.exercise.AndroidRadioGroup;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.RadioButton;
import android.widget.Toast;

public class AndroidRadioGroup extends Activity {

RadioButton myOption1, myOption2, myOption3;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myOption1 = (RadioButton)findViewById(R.id.option1);
myOption2 = (RadioButton)findViewById(R.id.option2);
myOption3 = (RadioButton)findViewById(R.id.option3);
myOption1.setOnClickListener(myOptionOnClickListener);
myOption2.setOnClickListener(myOptionOnClickListener);
myOption3.setOnClickListener(myOptionOnClickListener);
myOption1.setChecked(true);
}

RadioButton.OnClickListener myOptionOnClickListener =
new RadioButton.OnClickListener()
{

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(AndroidRadioGroup.this,
"Option 1 : " + myOption1.isChecked() + "\n"+
"Option 2 : " + myOption2.isChecked() + "\n" +
"Option 3 : " + myOption3.isChecked(),
Toast.LENGTH_LONG).show();

}


};
}


Download the files.