Cannot load new blank activity - android tutorial - android

I am a new android developer and encountered a problem while following the tutorial on Android's site - http://developer.android.com/training/basics/firstapp/starting-activity.html
My program loads on the emulator fine, but when you type something into the EditText and then hit the send button, a window pops up saying "App has stopped working". It seems as though my new activity isn't being created and I'm not sure as to why. I've scoured the web (and my code) to see if I could get a solution but did so to no avail. Any help would be appreciated.
The code for my first activity:
package com.example.appli;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends Activity {
public final static String EXTRA_MESSAGE = "com.example.myapp.MESSAGE";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.testlayout);
//////Button myButton = (Button) findViewById(R.id.my_button); //Told in tutorial to put this in onCreate
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
/** Called when the user selects the Send button */
public void sendMessage(View view) {
// Do something in response to button
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.edit_message);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}
}
The code for my second activity (the one being called)
package com.example.appli;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class DisplayMessageActivity extends Activity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//get message from intent
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
// Create the text view
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
setContentView(textView);
}
}
The Manifest
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.appli"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity android:name="com.example.myapp.DisplayMessageActivity" />
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

In AndroidManifest File you have declared incorrect package
change
<activity android:name="com.example.myapp.DisplayMessageActivity" />
to
<activity android:name="com.example.appli.DisplayMessageActivity" />
or just
<activity android:name=".DisplayMessageActivity" />

you have declared only one Activity that's also wrong package name
already your manifest has the package name
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.appli"
so just declare like this
<activity android:name=".DisplayMessageActivity" />
and you need to add this in your manifest also
<activity android:name=".MainActivity />
remove the target SDK version that you mentioned
android:targetSdkVersion="15"

Try this
<activity android:name=".DisplayMessageActivity"/>
Instead of
<activity android:name="com.example.myapp.DisplayMessageActivity" />
in your Manifest.xml file.

You has defined the package package com.example.appli; in your activities.
Why have you defined you activity in manifest like <activity android:name="com.example.myapp.DisplayMessageActivity" />?
Replace this line with
<activity android:name=".DisplayMessageActivity" />.

Related

Application crashes upon new Activity

I know and I do understand that this question has been asked, but I can't seem to interpret it for my application. I am creating an application - using Android Studio - that opens a Activity (called 'About'). When a user clicks on the 'about button' on my MainActivity, it should launch the 'About' activity. However, when I test this out on my device, it says the app has stopped. And on my output panel, it says something about an error with my Manifest.xml file?
MainActivity:
package com.msp.supercarsounds;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void clickedAbout(View view) {
final int result = 1;
Intent AboutButtonClicked = new Intent (this, About.class);
AboutButtonClicked.putExtra("About", "MainActivity");
startActivityForResult(AboutButtonClicked, result);
}
}
AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest
xmlns:android="http://schemas.android.com/apk/res/android"
package="com.msp.supercarsounds">
<uses-sdk android:minSdkVersion="17"
android:targetSdkVersion="22"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Thank you for your help and time!
You have to declare About activity
<activity android:name=".About">
</activity>
Add this below the </activity> tag of MainActivity
your second activity "about" is not added to manifest.xml add this under the mainactivity
<activity android:name=".about">/activity>

Unable to find explicit activity class exception even if the class is declared in the projects manifest

I transformed my project into a library. This project just displays a blank activity. I imported this library into another project where I want to call it thru the projects main activity but I keep on getting the error below even if I already declared the activity inside the projects manifest.
Unable to find explicit activity class {com.package.name/com.package.name.BatibotActivity}; have you declared this activity in your AndroidManifest.xml?
This is my project manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="pak.paks.pocket" >
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme" >
<activity android:name=".MainActivity" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.package.name.BatibotActivity"
android:screenOrientation="portrait" >
</activity>
</application>
</manifest>
What am I doing wrong?
edit:
this is my BatibotActivity
package com.package.name;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class BatibotActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_batibot);
}
}
EDIT2
This is the class that is calling the BatibotActivity
package pak.paks.pocket;
import android.content.ComponentName;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void submitBtn(View view) {
Intent intent = new Intent(android.content.Intent.ACTION_VIEW);
intent.setComponent(new ComponentName("com.package.name",
"com.package.name.BatibotActivity"));
startActivity(intent);
}
}
By the log message, you are trying to open com.package.name/com.package.name.BatibotActivity, but the Activity registered on AndroidManifest.xml is pak.paks.pocket/com.package.name.BatibotActivity.
The first parameter for ComponentName is the package name. This is the correct code:
Intent intent = new Intent(android.content.Intent.ACTION_VIEW);
intent.setComponent(new ComponentName("pak.paks.pocket", "com.package.name.BatibotActivity"));
startActivity(intent);
Please check your manifest tag's package attr.
<manifest package="com.package.name">
<application>
...
</application>
</manifest>

Unfortunately [yourapp], has stopped

I'm using intent method to make a simple app that takes you from main screen [with an enter button] to another screen which has three options. Code sourced online and seems to be error free, though my app crashes saying "Unfortunately [yourapp], has stopped" immediately after i press the button which is meant to take to the the other screen.
This is my first activity code:
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.view.View;
import android.view.View.OnClickListener;
public class MainActivity extends Activity {
Button button;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addListenerOnButton();
}
public void addListenerOnButton() {
final Context context = this;
button = (Button) findViewById(R.id.enterBtn);
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
Intent intent = new Intent(context, HomeActivity.class);
startActivity(intent);
}
});
}
}`
And this is my landing screen's activity code:
import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
public class HomeActivity extends Activity {
Button button;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home);
}
}
I'm really stuck with this issue and any help would be much appreciated. Many thanks in advance.
Every activity needs to be added in your manifest file under application tag. This seems to be the problem in your case.
Try to post you LogCat so that we might get some more information and if you have not yet added your Activity in the manifest, this is the way of adding it (Activities go under application tag)
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.southmp3"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="21" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
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=".HomeActivity"
android:label="#string/app_name" >
</activity>
</application>
all the Activities should be going under the application tag
I had forgotten to register my new activity on the androidmanifest.xml file. That's what sorted my app crash issue.

SearchView not searching

I am trying to implement search functionality in my android app using SearchView within the layout of my app. I purposefully chose to have it in the layout rather than in the Action Bar.
The problem is that once I type the search text and hit the enter/search key on the keyboard nothing happens. The searchable intent is never called. I feel like I must be missing something that is causing the search not to trigger
I apologize if I haven't included the code in the correct format below. Please let me know if there is any additional information that would help. Thanks in advance!
Manifest
<uses-sdk
android:minSdkVersion="11"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.lotr.arda.MainActivity"
android:label="#string/app_name" >
</activity>
<activity
android:name=".WebActivity"
android:theme="#android:style/Theme.NoTitleBar" >
</activity>
<activity
android:name=".menuActivity"
android:theme="#android:style/Theme.NoTitleBar" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.google.ads.AdActivity" android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize">
</activity>
<activity android:name=".searchActivity" >
<intent-filter>
<action android:name="android.intent.action.SEARCH" />
</intent-filter>
<meta-data android:name="android.app.searchable"
android:resource="#xml/searchable"/>
</activity>
</application>
</manifest>
Res/XML/search
<?xml version="1.0" encoding="utf-8"?>
<searchable xmlns:android="http://schemas.android.com/apk/res/android"
android:label="#string/app_name"
android:hint="#string/searchhint" >
</searchable>
SearchActivity.java
package com.lotr.arda;
import android.app.ListActivity;
import android.app.SearchManager;
import android.content.Intent;
import android.os.Bundle;
public class searchActivity extends ListActivity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.search_page);
// Get the intent, verify the action and get the query
Intent intent = getIntent();
if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
String query = intent.getStringExtra(SearchManager.QUERY);
System.out.println(query);
//doMySearch(query);
}
}
}
menuActivity.java (layout where searchview is located)
package com.lotr.arda;
import com.google.ads.AdRequest;
import com.google.ads.AdView;
import android.app.Activity;
import android.app.SearchManager;
import android.app.SearchableInfo;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.SearchView;
public class menuActivity extends Activity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.menu_page);
try{
AdView myad = (AdView) findViewById(R.id.ad);
AdRequest adRequest = new AdRequest();
myad.loadAd(adRequest);
SearchManager searchManager = (SearchManager)getSystemService(SEARCH_SERVICE);
SearchableInfo searchableInfo = searchManager.getSearchableInfo(getComponentName());
SearchView sv = (SearchView)findViewById(R.id.searchView1);
sv.setSearchableInfo(searchableInfo);
Button alpha = (Button)this.findViewById(R.id.button1);
alpha.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(menuActivity.this, MainActivity.class);
startActivity(intent);
}});
}catch(Exception e) {System.out.println(e.toString());}
}
}
You are missing a SearchView#setOnQueryTextListener. You'll need to override the OnQueryTextSubmit() method to actually perform and handle your search.
EDIT: I am assuming you're querying a database and using a Cursor for the results.
mSearchView.setOnQueryTextListener(new OnQueryTextListener()
{
#Override
public void onQueryTextSubmit(String query) {
Cursor c = getContentResolver.query(URI, null, "col_1 = ? OR col_2 = ?", new String[] { query, query }, null);
//Do whatever you want with your Cursor here
}
}
);
For a quick look it seems you missed default_searchable setting in your AndroidManifest.
Under activity setting for MainActivity, you should add this
<meta-data
android:name="android.app.default_searchable"
android:value=".WebActivity" />
Make sure your searchables.xml file is in the correct location (i.e, in your res/xml/ folder) and that the same file does not contain any errors - otherwise you will find that (SearchManager)getSystemService(Context.SEARCH_SERVICE).getSearchableInfo(componentName) will return null, breaking your search functionality.
(Also, ensure you set componentName in the appropriate manner, because the example shown in the Android guide is for only when you are making searches and displaying searches in the same Activity.)

Android Application Crashing

I'm trying to make my application start another class.
What im trying to learn is how to get another class to run in the background - like if the user opens the application, the application stays running.
I thought if I could try to open another class by using an intent, it would work. When i run my application on the emulator, it just crashes...
Here is the opening:
package omg.justry;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
public class MainActivity extends Activity {
#Override
//super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_main);
public void onCreate(Bundle savedInstanceState) {
Intent openStartingPoint = new Intent("omg.justtry.PartF**king2");
startActivity(openStartingPoint);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
Here is the "PartF**king2" class:
package omg.justry;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.widget.Toast;
public class PartF**king2 extends Activity{
public void onCreate(Bundle savedInstanceState) {
Context context = getApplicationContext();
CharSequence text = "Hello toast!";
int duration = Toast.LENGTH_SHORT;
Toast toast = Toast.makeText(context, text, duration);
toast.show();
}
}
The thing is, Eclipse doesn't show any errors. I just exported the app and installed it to the emulator using adb.
I also added the class to the AndroidManifest as you see here:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="omg.justry"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="PartF**king2"></activity>
</application>
I think its the manifest now that I look at it but whatever i do, it gets an error or crashes with Eclipse not explaining anything.
In every class, you onCreate(Bundle savedInstanceState) method MUST contain
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
The super is absolutly mandatory, and the setContentView defines the layout for your activity.
And an Activity cannot "run in the background". Start by reading some Android tutorial, and you'll have some clues about what to do.

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