Android app crash: Unable to instantiate activity ComponentInfo - android

07-18 04:48:22.465: E/AndroidRuntime(19105): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.liamwli.fa.yearbook/com.liamwli.fa.yearbook.Home}: java.lang.NullPointerException
That is the error I get.
I have defined the Home class in the manifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.liamwli.fa.yearbook"
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/app_name"
android:theme="#android:style/Theme.Holo" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Home"
android:label="#string/app_name"
android:theme="#android:style/Theme.Holo" >
<intent-filter>
<action android:name="com.liamwli.fa.yearbook.HOME" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>
And it only started doing this when I added the putExtras line in my main activity:
enter.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
myname = name.getText().toString();
Intent i = new Intent("com.liamwli.fa.yearbook.HOME");
i.putExtra("myname", myname);
startActivity(i);
}
});
So, can anyone please explain what is happening?

use this:
Intent i = new Intent(context,otherActivity.class);
context of that activity from where you want to start activity.otherActivity is the name of activity which you want to start

Try this once
Intent i = new Intent(MainActivity.this,Home.class);
i.putExtra("myname", myname);
startActivity(i);
And I don't think this is required in Manifest
<intent-filter>
<action android:name="com.liamwli.fa.yearbook.HOME" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>

change like this
Intent i = new Intent(MainActivity.this, Home.class);
i.putExtra("myname", myname);
startActivity(i);

Try this...
Intent i = new Intent( YourActivityName.this , otherActivity.class);

Ok, I looked and it looked like I was setting a variable contents outside of the onCreate method. So that is why it wasn't working.

Related

How to open an activity in a package subfolder from another activity?

I have problem with my manifest. When I try to open the second Activity, I get the error android.content.ActivityNotFoundException: No Activity found to handle Intent { act=com.xxxxx.monapplication.APPLICATION.OWNERREGISTRATION }
Find bellow my Manifest .xml contain
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.xxxxx.monapplication" android:versionCode="1" android:versionName="1.0" >
<uses-sdk android:minSdkVersion="15" android:targetSdkVersion="23" />
<application android:allowBackup="true" android:icon="#mipmap/ic_launcher" android:label="#string/app_name" android:supportsRtl="true" android:theme="#style/AppTheme" >
<activity android:name="com.xxxxx.monapplication.application.Accueil" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.xxxxx.monapplication.application.OwnerRegistration" >
<intent-filter>
<action android:name="android.intent.action.APPLICATION.OWNERREGISTRATION" />
<category android:name="android.intent.category.APPLICATION.DEFAULT" />
</intent-filter>
</activity>
An the part of my code to open second activity
btnMel.setOnClickListener( new View.OnClickListener()
{
#Override
public void onClick(View v)
{
Intent i = new Intent("com.xxxxx.monapplication.APPLICATION.OWNERREGISTRATION");
startActivity(i);
}
}
Please help me to find the error.
You can call activity by its class name, then put your custom intent to setAction.
private String YOUR_ACTION = "com.xxxxx.monapplication.APPLICATION.OWNERREGISTRATION"
//uou can use this instead.
//Intent i = new Intent(this /* caller context */, OwnerRegistration.class);
Intent i = new Intent();
i.setAction(YOUR_ACTION);
startActivity(i);
try this code..
Intent myIntent = new Intent(YourActivity.this, OWNERREGISTRATION.class); startActivity(myIntent);

Android Splash activity not redirecting

I have created a splash activity for my app. I am trying to redirect from my Splash activity to the Starting Point activity using AndroidManifest.xml but its not working. The Splash class loads up, and then it doesn't redirect to the Starting Point. And it doesn't give any errors either.
So can you please help me figure it out.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.myapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.myapp.Splash"
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="com.example.myapp.StartingPoint"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.example.myapp.STARTINGPOINT" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>
Now I have also tried
<activity
android:name=".Splash"
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=".StartingPoint"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.example.myapp.STARTINGPOINT" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
So what can I do here. I am not getting redirected from Splash to my Starting Point.
Splash Code
package com.example.myapp;
import android.app.Activity;
import android.os.Bundle;
public class Splash extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
}
}
Add this code to your Splash.java
Thread timer = new Thread(){
public void run(){
try {
sleep(2000);
} catch (Exception e) {
// TODO: handle exception
} finally{
Intent i = new Intent(Flash_Activity.this, StartingPoint.class);
startActivity(i);
}
}
};
timer.start();
}
You are never calling anything to change the activity from your splash to the starting point. This thread will do that.
Use this easy way to redirect to acitvity
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
Intent intent = new Intent(this,MainActivity.class);
startActivity(intent);
finish();
}
},2500);

unable to find activity

I have two Activity in my project.One is MainActivity and another is upload File.
On button click it gives me error like: unable to find activity.
This is code where i declared it in manifest:
<activity
android:name=".UploadFile"
android:label="#string/app_name"
>
</activity>
This is code by where i am calling uploadfile activity:
btnUpload.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent i=new Intent(MainActivity.this,UploadFIle.class);
startActivity(i);
}
});
Intent i=new Intent(MainActivity.this,UploadFIle.class); Is this a typo? Notice FIle.
you have UploadFIle in Code but UploadFile in manifest UploadFIle vs UploadFile
Make sure all of your activitiess are declared in the manifest.
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<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=".UploadFile"
android:label="#string/app_name" >
<intent-filter>
<category android:name="android.intent.action.MAIN" />
</intent-filter>
</activity>

Android app force closing after splash screen

I have a splash screen with a timer that runs for 3 seconds. After the 3 seconds it is supposed to auto load another activity called Dashboard. I made a new class that I want to have load after the splash screen called WelcomeSplash. I changed the classes in the splash screen from Dashboard to WelcomeSplash and the app force closes and the logcat says it has a null point exception. Here is the snip of code from the splash class and logcat snip.
02-13 23:18:46.826: E/AndroidRuntime(2475): FATAL EXCEPTION: main
02-13 23:18:46.826: E/AndroidRuntime(2475): java.lang.RuntimeException: Unable to start
activity ComponentInfo{com.magicbuddy.gamble/com.magicbuddy.gamble.welcomeSplash}:
java.lang.NullPointerException
02-13 23:18:46.826: E/AndroidRuntime(2475): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
Here is the snip of the Splash code
startActivity(new Intent(Splash.this, welcomeSplash.class));
When I change the welcomeSPlash.class to Dashboard.class the app does not force close. Here is the welcomeSplash Activity,
public class welcomeSplash extends Activity implements OnClickListener {
Button btnskip;
Button btnplay;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.welcome);
btnskip =(Button) findViewById(R.id.btnSkip);
btnskip.setOnClickListener(this);
btnplay =(Button) findViewById(R.id.btnOk);
btnplay.setOnClickListener(this);
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnSkip:
Intent a = new Intent(welcomeSplash.this, Dashboard.class);
startActivity(a);
break;
case R.id.btnOk:
Intent i = new Intent(welcomeSplash.this, Profile.class);
startActivity(i);
break;
}
}
}
THe manifest is copied below too.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.magicbuddy.gamble"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.magicbuddy.gamble.Splash"
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="com.magicbuddy.gamble.welcomeSplash"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.magicbuddy.gamble.Dashboard" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity
android:name="com.magicbuddy.gamble.Dashboard"
android:label="#string/app_name" >
</activity>
<activity
android:name="com.magicbuddy.gamble.MainActivity"
android:label="#string/app_name" >
</activity>
<activity
android:name="com.magicbuddy.gamble.Player"
android:label="#string/app_name" >
</activity>
<activity
android:name="com.magicbuddy.gamble.Menu"
android:label="#string/app_name" >
</activity>
<activity
android:name="com.magicbuddy.gamble.Popup"
android:label="#string/title_activity_popup" >
</activity>
</application>
</manifest>
Remove this code from your menifest
<intent-filter>
<action android:name="com.magicbuddy.gamble.Dashboard" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>

android intent filter?

I'm feeling stupid.This is very clear but I can not solve my problem.So excuse me for my question.
My problem is in about intenfilter.This is application tag of my manifest file:
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<activity
android:label="#string/app_name"
android:name=".AlakyTestActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:label="reza"
android:name=".A2" >
<intent-filter >
<action android:name="MAIN" />
<category android:name="LAUNCHER" />
</intent-filter>
</activity>
</application>
And this is my button click listener:
b1 = (Button)findViewById(R.id.button1);
b1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent2 = new Intent();
intent2.setAction("MAIN");
intent2.addCategory("LAUNCHER");
startActivity(intent2);
}
});
I think that all things is good but when I run my code and click on b1,I get this erroe:
android.content.ActivityNotFoundException: No Activity found to handle Intent { act=MAIN cat=[LAUNCHER] }
Edit:
This is A2:
public class A2 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
this.setContentView(R.layout.main2);
}
}
Please help me.
You should set the android:name of the second activity to the (package name).(the class)
for example, lets say the second activity class is 'com.my.app.reza' you should add you the manifest:
<activity
android:label="#string/app_name"
android:name=".reza" >
<intent-filter >
<action android:name="com.my.app.REZA" />
<category android:name="android.intent.category.DEFUALT" />
</intent-filter>
</activity>
and you should start the activity like that:
Intent intent = new Intent("com.my.app.REZA");
startActivity(intent);
NOTE that it isn't the best way to do it, you shouldn't mess to much with package name I'd recommend you to do it the following way:
<activity
android:label="#string/app_name"
android:name=".reza" />
and start it like that:
startActivity(new Intent( this.getContext() , reza.class );
Please use like that:
Intent intent2 = new Intent(context,A2.class);
startActivity(intent2);
android:name=".A2" ,you must have "A2" activity class implement!
Modify to android:name=".A2", not android:name="A2"!
You don't need to specify category if you just need to call A2 inside your app. And you should set an unique action name, for example it can be a hash string:
...
Intent intent2 = new Intent("a202bfa923069ee8e119205e3468ee131ceafda37");
startActivity(intent2);
Note that action name uses same rule as package name.
<intent-filter>
<action android:name="com.blacky.basictutorial.TutorialTwo" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
Try to use this in your second activity and call by the following code:
startActivity(new Intent("com.blacky.basictutorial.TutorialTwo"));
Hope this will work for you.

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