Develop Reference

Double ActionBar appears?

this is my first app for android, I've been an iPhone dev for 3 years, it's been a change of mindset, and I still find some things odd. First I don't know if this iPhone background might be causing some troubles, but here's what I'm trying to do:
I want to implement an ActionBar with two options working like a TabBar from iOS:
What I want is that when the user selects an action, some Activity will be presented to the user.
Here's what I'm doing so far (which isn't that much):
I'm Using ActionBarSherlock, I have 3 activities: myApp, First and Second
myapp.java only creates the ActionBar elements and loads the activity_first:
package com.example.myApp;
import com.actionbarsherlock.ActionBarSherlock;
import com.actionbarsherlock.view.MenuItem;
import android.os.Bundle;
import com.actionbarsherlock.ActionBarSherlock.OnCreateOptionsMenuListener;
import com.actionbarsherlock.app.SherlockActivity;
import com.actionbarsherlock.view.Menu;
public class myApp extends SherlockActivity implements OnCreateOptionsMenuListener {
ActionBarSherlock mSherlock = ActionBarSherlock.wrap(this);
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setTitle("myApp");
mSherlock.setContentView(R.layout.activity_first);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
menu.add("First")
.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM | MenuItem.SHOW_AS_ACTION_WITH_TEXT);
menu.add("Second")
.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM | MenuItem.SHOW_AS_ACTION_WITH_TEXT);
return true;
}
}
The activities have nothing so far, apart from the generated stub:
import android.app.Activity;
import android.os.Bundle;
public class First extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first);
}
}
So I have 1 Question and 1 problem:
Question: Is this the correct use of an ActivityBar? I mean, should it be used to switch activities?
Problem: As you can see in the OnCreate method of myApp class, I'm loading the activity_first, It does load the activity, however it loads the ActionBar Twice, like so:
I don't get why is it being loaded twice. If I remove the line: mSherlock.setContentView(R.layout.activity_first); it loads the Bar once, obviously I need to load the activity...
Also I've assigned the NoActionBar theme to the activity_first in the graphical editor of the XML (activity_first.xml), but it doesn't work. What Can I do to load it just once.
Thank you for your valuable time.

Is this the correct use of an ActivityBar? I mean, should it be used to switch activities?
You can think of "First" and "Second" as being the equivalent of toolbar buttons in a desktop app. You are welcome to have those action bar items start up activities if you wish.
As you can see in the OnCreate method of myApp class, I'm loading the activity_first, It does load the activity, however it loads the ActionBar Twice, like so:
Delete this line:
ActionBarSherlock mSherlock = ActionBarSherlock.wrap(this);
and change mSherlock.setContentView(R.layout.activity_first); to just setContentView(R.layout.activity_first);. I believe that will clear up your problems.

Hide MainActivity window in phonegap application

I am developing an android app using phonegap (cordova-2.1.0).
My MainActivity.java code is as following -
package com.app.myapp;
import android.os.Bundle;
import org.apache.cordova.*;
public class MainActivity extends DroidGap {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
super.loadUrl("file:///android_asset/www/index.html");
}
}
Problem : Whenever I start the application, it shows MainActivity window first and then show the actual HTML code. Is there any way to get rid of MainActivity and show the HTML directly?
Thanks in Advance...

Add this to your AndroidManifest application tag:
android:theme="#android:style/Theme.NoTitleBar"
Should do the trick.

Android Manifest Editor not working properly

Ubuntu 11.10 ADT 16.01 Java 6 Eclipse Java EE Indigo SR1 - All latest release following android dev requirements.
I am just starting to learn coding for android and got to a tutorial on switching Activities. Using the New project android template, I made another test activity class identical to the first except for name.
package com.test.SwitchActivity;
import android.app.Activity;
import android.os.Bundle;
public class SwitchActivityActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}
The problem is that when I use the Menifest editor edit the AndroidManifest.xml file - add button for the Application Node, the listbox is empty. All the tutorials I have found are populated with xml tag choices. Now, I can add the xml data manually - it is no problem. What is driving me nuts is not being able to figure out why it does not work for me as it is supposed to work. I don't find other people having the issue and I have re-installed everything at least once before coming here to post another question.
I just want to finish the tutorial and switch between two activities.
Here is a screenshot of what I describe. Anyone have any ideas as to why it does not work?
http://i.stack.imgur.com/Fwfbz.png

To create another activity
Create a new class "myactivity.java" that extends the Activity
Create android xml file with your UI items in it lets call it exampleactivity.xml (it should be in small letters with .xml extension and should be saved in res/layout folder).
In myactivity.java add the following method (same as above except exampleactivity replaced main)
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.exampleactivity);
}
}
create a button changeactivity in SwitchActivityActivity and initialize it in onCreate method of SwitchActivityActivity via
changeactivity = (Button) findViewById(R.id.newActivityButton);
create the following in onCreate method of SwitchActivityActivity
changeactivity.setOnClickListener(new OnClickListener() {
Intent i;
public void onClick(View v) {
i = new Intent(Intent.ACTION_DEFAULT);
i.setClass(SwitchActivityActivity.this, myactivity.class);
startActivity(i);
}
});
In the main.xml create a button and give the button id by
android:id="#+id/newActivityButton"
Finally add the following in AndroidManifest file after the SwitchActivityActivity activity tag
compile and run it.

please explain this block of code

I found this on android developers when i was trying to program a button:android developers blog: UI framework changes in Android 1.6
With Android 1.6, none of this is necessary. All you have to do is declare a public method in your Activity to handle the click (the method must have one View argument):
class MyActivity extends Activity { public void myClickHandler(View target){
// Do stuff
}
}
And then reference this method from your XML layout:
<Button android:onClick="myClickHandler" />
can smeone please explain this code to me? I am a beginner in programming, and I don't know what to put in the //do stuff space? I need to reference another activity so i can open another screen. And do i still need to have an activity and put a block of program in the class? this is the code i am using in the class at the moment. Please tell me if i need to update it to use this method:
package com.duncan.hello.world;
import com.duncan.hello.world.R;
import android.app.Activity;
import android.os.Bundle;
public class OtherActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.other);
}
}

You put what you want to happen when the button is clicked in the // do stuff part.
You only need to update your code if you're using a button click handler in this fashion.
You might want to start with something a bit simpler, and perhaps not target Android 1.6.

I cant import MapView for android project

public class ActivityGoogleMaps extends MapActivity {// map view shows as an error
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}
I try to import this:
import com.google.android.maps.MapActivity;
but when i type com. - google doesnt appear..

1- Go to Project Properties
2- From android tab, select Google API for your target platform
(for 2.2, select Google APIs-Platform 2.2 and things like that)
I think this can solve the problem

you will have to add map.jar to libs. though it is automatically added when we extends MapActivity.