I have created two classes: Example1 and Example2, which extends activity.
Example1 contains a UI of buttons, while Example2 contains UI of TextEdit. I want to call Example2 when a button is clicked, so this code is in an onclick method
Intent i = new Intent();
i.setClassName("com.a.ui", "com.a.ui.Example2");
startActivity(i);
So I am able to get the UI of Example2 successfully. What's an alternate way of calling intent?
Is there any alternate way to start an activity?
you can call like this:
startActivity(new Intent(com.a.ui.this, com.a.ui.Example2.class));
You can try this way.
Intent i = new Intent(com.a.ui.this, com.a.ui.Example2.class);
startActivity(i);
And remember to include the Activity in your Manifest.xml
e.g.
<activity android:name=".SampleActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
Related
To specify my "Home" activity at compile-time, I can use the following code in my AndroidManifest.
<activity
android:name=".HomeActivity"
<intent-filter android:label="#string/home_activity">
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.HOME" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
I have a requirement though where I need to be able to specify the activity I would like to use as my "Home" screen at "run-time". Does anyone know if this is possible? Basically, I want to replace "HomeActivity" with something else.
I looked into using an "activity-alias" where I can specify the target activity using the "targetActivity" attribute but I didn't quite get how I can use this.
Thanks!
#Jon you can conditionally call separate activity from splash.Like you have a condition that on first app launch you need to open a tutorial screen and then onwards your home Activity then you can create different intents.
if (!sharedPreferences.contains(DiceConstants.FIRST_TIME_PREFS)) {
intent = new Intent(this, TutorialActivity.class);
sharedPreferences.edit().putBoolean(DiceConstants.FIRST_TIME_PREFS, true).commit();
} else {
intent = new Intent(this, HomeActivity.class);
}
Hello I am fairly new to Andriod. I have three activities A B C. A is the MainActivity B and C are independent activities. I have included a calendar in the mainActivity and have highlighted some dates.
Now through mainActivity I start a new activity B and return back to A using the following code
public void OnClick(View V){
Intent i= new Intent(getApplicationContext(),A.class);
i.setFlags(Imtent.FLAG_ACTVITIY_CLEAR_TOP);
startActivity(i);
}
This returns back to the mainActivity but the Highlighted dates are not there. I want to know whether the creates a fresh new Activity or I have done something wrong in highlighting the days.
You should use the following row in your manifest to MainActivity:
...
android:launchMode="singleTask"
...
For example:
<activity
android:name=".activities.MainActivity"
android:label="#string/app_name"
android:launchMode="singleTask"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<action android:name="android.nfc.action.NDEF_DISCOVERED" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
No need to start the previous activity again. You can just call this.finish() whenever you want to close the current activity and return to the previous one. If this is the last activity in the BackStack, the app will close.
I'm trying to call main activity using implicit intents. I give both action and category in intent but before starting the activity android system gives me a list of applications to select from for opening the activity.
Code snippet I am using to call the main activity follows:
protected void initiateActivity(int requestCode, String value, String oper) {
Intent i = new Intent("android.intent.action.MAIN");
i.addCategory("android.intent.category.LAUNCHER");
i.putExtra("VALUE", value);
i.putExtra("OPER", oper);
startActivityForResult(i, requestCode);
}
It seems to me that every app in system will be having same action, category combo, hence android is giving me that list of apps to select from. What changes can I make to my Main Activity so that this issue is not seen?
Looks like you might need to separate out with intent-filters. It looks there is a good explanation in this post:
How can I start MAIN activity with the help of <intent-filter>?
Which recommends adding the filters such as these below or you will be calling the launcher:
<activity android:name=".MyActivity"
android:configChanges="orientation|keyboardHidden"
android:windowSoftInputMode="stateHidden"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="com.package.name.MyAction"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
I'm using this code to refresh MainActivity.java when a Refresh button is pressed.
Intent intent = getIntent();
finish();
startActivity(intent);
MainActivity.java has the category default and there is another Launcher activity. So whenever I press the Refresh button the Launcher Activity also starts again. I only need to start the MainActivity class. Below is the manifest
<application
android:allowBackup="true"
android:icon="#drawable/play_icon"
android:label="#string/app_name"
android:theme="#style/CustomActionBarTheme" >
<activity
android:name="com.theanilpaudel.joshilo.FirstScreen"
android:configChanges="orientation|screenSize"
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.theanilpaudel.joshilo.MainActivity"
android:configChanges="orientation|screenSize"
android:label="#string/app_name"
android:theme="#style/Theme.AppCompat.Light.DarkActionBar" >
<intent-filter>
<action android:name="android.intent.action.MAINACTIVITY" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
What you are looking for in this case is an explicit Intent that launches MainActivity.
You can do this like so:
Intent mainIntent = new Intent(this, MainActivity.class);
startActivity(mainIntent);
This will ensure that the Intent only launches MainActivity.
However, I highly recommend re-evaluating why you need to completely restart the Activity to refresh it. There are much cheaper (faster and less resource intensive) methods of updating data displayed in an Activity.
I guess I know the culprit. Try using the following code once.
Intent intent = getIntent();
startActivity(intent);
finish();
As far as I know startActivity() uses context to run. In case if you call finish() before startActivity() that may lead to destroy context of MainActivity and will get the application's context i.e. fires the activity with behavior LAUNCHER or MAIN.
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
Let me know if it helps or you still have difficulty reloading activity.
Cheers
I have activity A in package one, and I want to run an intent which will up an activity B which is in package two.
How can I do this? Any samples will be welcome.
this is what ive done, and the error i get:
first activity ("MainActivity") in a package: com.abelski.currencyclient
and second activity("SecondActivity" in a diffrent package: com.idan.second
now i wanna call from MainActivity to SecondActivity.
ive added this line at the manifest of the MainActivity:
<activity android:name="com.idan.second.SecondApplicationActivity"></activity>
now in main Activity i got this button which run this line:
Intent intent = new Intent(MainActivity.this,SecondApplicationActivity.class);
and this is the rror:
04-29 09:20:59.197: ERROR/AndroidRuntime(399): Uncaught handler: thread main exiting due to uncaught exception
04-29 09:20:59.276: ERROR/AndroidRuntime(399): java.lang.NoClassDefFoundError: com.idan.second.SecondApplicationActivity
04-29 09:20:59.276: ERROR/AndroidRuntime(399):
I am assuming that by "packages" you mean applications.
We have:
- ApplicationA with FirstActivity
- ApplicationB with SecondActivity
If, in the ApplicationB's AndroidManifest.xml file, in the declaration of SecondActivity you add an intent filter such as:
<activity android:name=".SecondActivity">
<intent-filter>
<action android:name="applicationB.intent.action.Launch" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
You can create an Intent to launch this SecondActivity from the FirstActivity with:
Intent intent = new Intent("applicationB.intent.action.Launch");
startActivity(intent);
What this all means is:
The SecondActivity has a filter for the intent action of "applicationB.intent.action.Launch"
When you create an intent with that action and call 'startActivity' the system will find the activity (if any) that responds to it
The documentation for this is at: https://developer.android.com/reference/android/content/Intent.html
I had the same problem and the solution was another level in the root of your package name.
If you have two packages "com.first...." and "com.second...", and the manifest is referencing "com.first". Then you can refactor both packages in order to reuse the first part. For instance, "com.package.first" and "com.package.second". Then your manifest has to be also updated
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.package">
...
<activity android:name=".first.FirstPackageActivity" android:label="FirstPackageActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name=".second.SecondPackageActivity" android:label="SecondPackageActivity">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
Your java code can create an intent and start the activity in the usual way:
Intent intent = new Intent(this,ActivityClassName.class);
startActivity(intent);
If the package you mentioned here is same to application,I think the answer in the question Android: Starting An Activity For A Different Third Party App is simpler。With the first answer to that question, you don't need to make any modification to your second application.
Use explicit intents:
Intent intent = new Intent(context,ClassName.class);
where ClassName is from another package.
Sometimes, you will not know the name of the class in such cases you will have to rely on the Intent that the target class advertises to handle.
First, you need to declare both packages and activities on Manifest :
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
and for the second activities, on android:name --> .Packages name.activity, assuming your second packages name com.iden.second :
<activity android:name=".second.SecondActivity">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".MainActivity" />
<intent-filter>
<action android:name="android.intent.action.SECOND" />
<category android:name="android.intent.category.SECOND" />
</intent-filter>
</activity>
then on the MAINACTIVITY JAVA CLASS, asuming you will start second activity using a button :
public class MainActivity extends AppCompatActivity {
private Button mButtonSecond;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButtonSecond = findViewById(R.id.btn_second);
mButtonSecond.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent newActivity = new Intent(MainActivity.this,com.iden.second.SECOND.class);
startActivity(newActivity);
}
});
}
}
hope that can help, since i am not clear with the question structure