Related
Hello at the moment I have a problem with calling a new activity.
I want to call a new Activity Inside my SettingsActivity.
I call the SettingsActivity by pressing an Button :
Button button = findViewById(R.id.button_navSecond);
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, SettingsActivityModern.class);
startActivity(intent);
}
});
But at the next Button click to get to another Acitivty inside this Activity I get back to the Mainactivity
premiumBuy.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(SettingsActivityModern.this, BuyPremiumActivity.class);
startActivity(intent);
}
});
It seems like it is not possible to Call startActivity(intent); inside an activty which was called with this command. So how to prevent that?
Try adding the Activity in the AndroidManifest.xml like this:
<activity
android:name="com.example.foodgent.YOUR_ACTIVITY" />
I'm new to android studio and i have a problem when I'm trying to jump to a new activity, so when the line is:
public class signup_activity extends AppCompatActivity {
ImageButton logupButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_signup_activity);
logupButton = findViewById(R.id.signuparrow);
logupButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, signup_activity.class);
startActivity(intent);
}
});
}}
I get the error:
'com.example.myapplication.MainActivity' is not an enclosing class
and i so a couple of of people advising to chane the intent to this instead of MainActivity.this
but when im changing to this i get the error:
Cannot resolve constructor 'intent'
Intent intent = new Intent(MainActivity.this, signup_activity.class);
Several things:
First, the first param of Intent() constructor is a context. Since you are on signup_activity you need to do signup_activity.this to use it as a context.
I'd assume you want to go to MainActivity, so your second param should be MainActivity.class. It seems you got the order altered there.
you are in signup_activity and when use Intent in fisrt part you should call the current contex to jump to other activity.
so you should replace
Intent intent = new Intent(signup_activity.this, MainActivity.class);
if you want to jump to signup_activity you can call intent from MainActivity.
In an Android application, how do you start a new activity (GUI) when a button in another activity is clicked, and how do you pass data between these two activities?
Easy.
Intent myIntent = new Intent(CurrentActivity.this, NextActivity.class);
myIntent.putExtra("key", value); //Optional parameters
CurrentActivity.this.startActivity(myIntent);
Extras are retrieved on the other side via:
#Override
protected void onCreate(Bundle savedInstanceState) {
Intent intent = getIntent();
String value = intent.getStringExtra("key"); //if it's a string you stored.
}
Don't forget to add your new activity in the AndroidManifest.xml:
<activity android:label="#string/app_name" android:name="NextActivity"/>
Current responses are great but a more comprehensive answer is needed for beginners. There are 3 different ways to start a new activity in Android, and they all use the Intent class; Intent | Android Developers.
Using the onClick attribute of the Button. (Beginner)
Assigning an OnClickListener() via an anonymous class. (Intermediate)
Activity wide interface method using the switch statement. (not-"Pro")
Here's the link to my example if you want to follow along:
Using the onClick attribute of the Button. (Beginner)
Buttons have an onClick attribute that is found within the .xml file:
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="goToAnActivity"
android:text="to an activity" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="goToAnotherActivity"
android:text="to another activity" />
In Java class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
}
public void goToAnActivity(View view) {
Intent intent = new Intent(this, AnActivity.class);
startActivity(intent);
}
public void goToAnotherActivity(View view) {
Intent intent = new Intent(this, AnotherActivity.class);
startActivity(intent);
}
Advantage: Easy to make on the fly, modular, and can easily set multiple onClicks to the same intent.
Disadvantage: Difficult readability when reviewing.
Assigning an OnClickListener() via an anonymous class. (Intermediate)
This is when you set a separate setOnClickListener() to each button and override each onClick() with its own intent.
In Java class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
Button button1 = (Button) findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(view.getContext(), AnActivity.class);
view.getContext().startActivity(intent);}
});
Button button2 = (Button) findViewById(R.id.button2);
button2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(view.getContext(), AnotherActivity.class);
view.getContext().startActivity(intent);}
});
Advantage: Easy to make on the fly.
Disadvantage: There will be a lot of anonymous classes which will make readability difficult when reviewing.
Activity wide interface method using the switch statement. (not-"Pro")
This is when you use a switch statement for your buttons within the onClick() method to manage all the Activity's buttons.
In Java class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
Button button1 = (Button) findViewById(R.id.button1);
Button button2 = (Button) findViewById(R.id.button2);
button1.setOnClickListener(this);
button2.setOnClickListener(this);
}
#Override
public void onClick(View view) {
switch (view.getId()){
case R.id.button1:
Intent intent1 = new Intent(this, AnActivity.class);
startActivity(intent1);
break;
case R.id.button2:
Intent intent2 = new Intent(this, AnotherActivity.class);
startActivity(intent2);
break;
default:
break;
}
Advantage: Easy button management because all button intents are registered in a single onClick() method
For the second part of the question, passing data, please see How do I pass data between Activities in Android application?
Edit: not-"Pro"
Create an intent to a ViewPerson activity and pass the PersonID (for a database lookup, for example).
Intent i = new Intent(getBaseContext(), ViewPerson.class);
i.putExtra("PersonID", personID);
startActivity(i);
Then in ViewPerson Activity, you can get the bundle of extra data, make sure it isn't null (in case if you sometimes don't pass data), then get the data.
Bundle extras = getIntent().getExtras();
if(extras !=null)
{
personID = extras.getString("PersonID");
}
Now if you need to share data between two Activities, you can also have a Global Singleton.
public class YourApplication extends Application
{
public SomeDataClass data = new SomeDataClass();
}
Then call it in any activity by:
YourApplication appState = ((YourApplication)this.getApplication());
appState.data.CallSomeFunctionHere(); // Do whatever you need to with data here. Could be setter/getter or some other type of logic
When user clicks on the button, directly inside the XML like that:
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextButton"
android:onClick="buttonClickFunction"/>
Using the attribute android:onClick we declare the method name that has to be present on the parent activity. So I have to create this method inside our activity like that:
public void buttonClickFunction(View v)
{
Intent intent = new Intent(getApplicationContext(), Your_Next_Activity.class);
startActivity(intent);
}
Intent iinent= new Intent(Homeactivity.this,secondactivity.class);
startActivity(iinent);
Intent in = new Intent(getApplicationContext(),SecondaryScreen.class);
startActivity(in);
This is an explicit intent to start secondscreen activity.
Emmanuel,
I think the extra info should be put before starting the activity otherwise the data won't be available yet if you're accessing it in the onCreate method of NextActivity.
Intent myIntent = new Intent(CurrentActivity.this, NextActivity.class);
myIntent.putExtra("key", value);
CurrentActivity.this.startActivity(myIntent);
Try this simple method.
startActivity(new Intent(MainActivity.this, SecondActivity.class));
From the sending Activity try the following code
//EXTRA_MESSAGE is our key and it's value is 'packagename.MESSAGE'
public static final String EXTRA_MESSAGE = "packageName.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
....
//Here we declare our send button
Button sendButton = (Button) findViewById(R.id.send_button);
sendButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//declare our intent object which takes two parameters, the context and the new activity name
// the name of the receiving activity is declared in the Intent Constructor
Intent intent = new Intent(getApplicationContext(), NameOfReceivingActivity.class);
String sendMessage = "hello world"
//put the text inside the intent and send it to another Activity
intent.putExtra(EXTRA_MESSAGE, sendMessage);
//start the activity
startActivity(intent);
}
From the receiving Activity try the following code:
protected void onCreate(Bundle savedInstanceState) {
//use the getIntent()method to receive the data from another activity
Intent intent = getIntent();
//extract the string, with the getStringExtra method
String message = intent.getStringExtra(NewActivityName.EXTRA_MESSAGE);
Then just add the following code to the AndroidManifest.xml file
android:name="packagename.NameOfTheReceivingActivity"
android:label="Title of the Activity"
android:parentActivityName="packagename.NameOfSendingActivity"
Intent i = new Intent(firstactivity.this, secondactivity.class);
startActivity(i);
Kotlin
First Activity
startActivity(Intent(this, SecondActivity::class.java)
.putExtra("key", "value"))
Second Activity
val value = getIntent().getStringExtra("key")
Suggestion
Always put keys in constant file for more managed way.
companion object {
val PUT_EXTRA_USER = "user"
}
startActivity(Intent(this, SecondActivity::class.java)
.putExtra(PUT_EXTRA_USER, "value"))
Starting an activity from another activity is very common scenario among android applications.
To start an activity you need an Intent object.
How to create Intent Objects?
An intent object takes two parameter in its constructor
Context
Name of the activity to be started. (or full package name)
Example:
So for example,if you have two activities, say HomeActivity and DetailActivity and you want to start DetailActivity from HomeActivity (HomeActivity-->DetailActivity).
Here is the code snippet which shows how to start DetailActivity from
HomeActivity.
Intent i = new Intent(HomeActivity.this,DetailActivity.class);
startActivity(i);
And you are done.
Coming back to button click part.
Button button = (Button) findViewById(R.id.someid);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent i = new Intent(HomeActivity.this,DetailActivity.class);
startActivity(i);
}
});
The way to start new activities is to broadcast an intent, and there is a specific kind of intent that you can use to pass data from one activity to another. My recommendation is that you check out the Android developer docs related to intents; it's a wealth of info on the subject, and has examples too.
You can try this code:
Intent myIntent = new Intent();
FirstActivity.this.SecondActivity(myIntent);
Start another activity from this activity and u can pass parameters via Bundle Object also.
Intent intent = new Intent(getBaseContext(), YourActivity.class);
intent.putExtra("USER_NAME", "xyz#gmail.com");
startActivity(intent);
Retrive data in another activity (YourActivity)
String s = getIntent().getStringExtra("USER_NAME");
// In Kotlin , you can do as
/* In First Activity, let in activity layout there is button which has id as button.
Suppose I have to pass data as String type from one activity to another */
val btn = findViewById<Button>(R.id.button)
btn.setOnClickListener {
val intent = Intent(baseContext, SecondActivity::class.java).apply {
putExtra("KEY", data)
}
startActivity(intent)
}
// In Second Activity, you can get data from another activity as
val name = intent.getStringExtra("KEY")
/* Suppose you have to pass a Custom Object then it should be Parcelable.
let there is class Collage type which I have to pass from one activity to another
*/
import android.os.Parcelable
import kotlinx.android.parcel.Parcelize
#Parcelize
class Collage(val name: String, val mobile: String, val email: String) : Parcelable
/* Activity First , let here data is Collage type. which I have to pass to another activity. */
val btn = findViewById<Button>(R.id.button)
btn.setOnClickListener {
val intent = Intent(baseContext, SecondActivity::class.java).apply {
putExtra("KEY", data)
}
startActivity(intent)
}
// then from second Activity we will get as
val item = intent.extras?.getParcelable<Collage>("KEY")
Button button = findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(SplashActivity.this,HomeActivity.class);
startActivity(intent);
}
});
Implement the View.OnClickListener interface and override the onClick method.
ImageView btnSearch;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_search1);
ImageView btnSearch = (ImageView) findViewById(R.id.btnSearch);
btnSearch.setOnClickListener(this);
}
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnSearch: {
Intent intent = new Intent(Search.this,SearchFeedActivity.class);
startActivity(intent);
break;
}
Although proper answers have been already provided but I am here for searching the answer in language Kotlin. This Question is not about language specific so I am adding the code to accomplish this task in Kotlin language.
Here is how you do this in Kotlin for andorid
testActivityBtn1.setOnClickListener{
val intent = Intent(applicationContext,MainActivity::class.java)
startActivity(intent)
}
The Most simple way to open activity on button click is:
Create two activities under the res folder, add a button to the first activity and give a name to onclick function.
There should be two java files for each activity.
Below is the code:
MainActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.content.Intent;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void goToAnotherActivity(View view) {
Intent intent = new Intent(this, SecondActivity.class);
startActivity(intent);
}
}
SecondActivity.java
package com.example.myapplication;
import android.app.Activity;
import android.os.Bundle;
public class SecondActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity1);
}
}
AndroidManifest.xml(Just add this block of code to the existing)
</activity>
<activity android:name=".SecondActivity">
</activity>
Take Button in xml first.
<Button
android:id="#+id/pre"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#mipmap/ic_launcher"
android:text="Your Text"
/>
Make listner of button.
pre.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, SecondActivity.class);
startActivity(intent);
}
});
When button is clicked:
loginBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent= new Intent(getApplicationContext(), NextActivity.class);
intent.putExtra("data", value); //pass data
startActivity(intent);
}
});
To received the extra data from NextActivity.class :
Bundle extra = getIntent().getExtras();
if (extra != null){
String str = (String) extra.get("data"); // get a object
}
Write the code in your first activity .
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(MainActivity.this, SecondAcitvity.class);
//You can use String ,arraylist ,integer ,float and all data type.
intent.putExtra("Key","value");
startActivity(intent);
finish();
}
});
In secondActivity.class
String name = getIntent().getStringExtra("Key");
Place button widget in xml like below
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
/>
After that initialise and handle on click listener in Activity like below ..
In Activity On Create method :
Button button =(Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new
Intent(CurrentActivity.this,DesiredActivity.class);
startActivity(intent);
}
});
An old question but if the goal is to switch displayed pages, I just have one activity and call setContentView() when I want to switch pages (usually in response to user clicking on a button). This allows me to simply call from one page's contents to another. No Intent insanity of extras parcels bundles and whatever trying to pass data back and forth.
I make a bunch of pages in res/layout as usual but don't make an activity for each. Just use setContentView() to switch them as needed.
So my one-and-only onCreate() has:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LayoutInflater layoutInflater = getLayoutInflater();
final View mainPage = layoutInflater.inflate(R.layout.activity_main, null);
setContentView (mainPage);
Button openMenuButton = findViewById(R.id.openMenuButton);
final View menuPage = layoutInflatter.inflate(R.layout.menu_page, null);
Button someMenuButton = menuPage.findViewById(R.id.someMenuButton);
openMenuButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
setContentView(menuPage);
}
});
someMenuButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
do-something-interesting;
setContentView(mainPage);
}
}
}
If you want the Back button to go back through your internal pages before exiting the app, just wrap setContentView() to save pages in a little Stack of pages, and pop those pages in onBackPressed() handler.
your button xml:
<Button
android:id="#+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="jump to activity b"
/>
Mainactivity.java:
Button btn=findViewVyId(R.id.btn);
btn.setOnClickListener(btnclick);
btnclick.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent();
intent.setClass(Mainactivity.this,b.class);
startActivity(intent);
}
});
imageView.setOnClickListener(v -> {
// your code here
});
Kotlin 2022
The simplest way:
val a = Intent(this.context, BarcodeActivity::class.java)
a.putExtra("barcode", barcode)
startActivity(a)
and in the other side (BarcodeActivity in my case):
val intent: Intent = intent
var data = intent.getStringExtra("barcode")
Read more here
I have an application where you can select an item from a AlertDialog spinner like, but I don't know how to make my app, to memorize the selected choice, and then behave my button to this. This is what I have now:
#Override
public void onClick(View v) {
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
public void run() {
mp = MediaPlayer.create(getApplicationContext(), R.raw.ais);
mp.start();
Intent myIntent = new Intent(MainActivity.this, Main2Activity.class);
MainActivity.this.startActivity(myIntent);
}
}, 9000);
Intent i = new Intent();
i.setAction(Intent.ACTION_MAIN);
i.addCategory(Intent.CATEGORY_HOME);
startActivity(i);
}
});
}
And somehow to this code, I want to add my last selected item button, for example:
If ( last selected item from AlertDialog was = dance)
do the code, that I wrote above.
One way to do it is with an interface. Define an interface in your Alert Dialog fragment and instantiate it like this:
public interface MyDialogListener {
//put whatever data you want to pass as a paramenter, below I have two examples
public void onDataSelectedEvent( String action);
}
MyDialogListener myListener;
The listener will have to be instantiated in the dialog by typecasting your activity to a MyDialogListener.
You could do it like this:
myListener = (MyDialogListener) MainActivity.this;
Or even better would be to use the activity parameter in the dialog's onAttach(...) method.
We are able to do this because later, we will make your activity implement the MyDialogListener interface, which will effectively make the activity a MyDialogListener.
Put this line in the method or listener, maybe an onClick() in your alert dialog. This is for a spinner:
myListener.onDataSelectedEvent(mySpinner.getSelectedItem().toString())
Implement the interface in your Activity that receives the data like this:
public class MyActivity extends Activity
implements MyAlertDialog.MyDialogListener{
Then, in the activity receiving the data, have the interface method look like this:
#Override
public void onDataSelectedEvent(String action) {
//probably better to use a switch statement
if(action == "dance") {
// dance()
} else if(action == "stand") {
.......etc
}
}
There is a good example here: http://developer.android.com/guide/topics/ui/dialogs.html#PassingEvents
In an Android application, how do you start a new activity (GUI) when a button in another activity is clicked, and how do you pass data between these two activities?
Easy.
Intent myIntent = new Intent(CurrentActivity.this, NextActivity.class);
myIntent.putExtra("key", value); //Optional parameters
CurrentActivity.this.startActivity(myIntent);
Extras are retrieved on the other side via:
#Override
protected void onCreate(Bundle savedInstanceState) {
Intent intent = getIntent();
String value = intent.getStringExtra("key"); //if it's a string you stored.
}
Don't forget to add your new activity in the AndroidManifest.xml:
<activity android:label="#string/app_name" android:name="NextActivity"/>
Current responses are great but a more comprehensive answer is needed for beginners. There are 3 different ways to start a new activity in Android, and they all use the Intent class; Intent | Android Developers.
Using the onClick attribute of the Button. (Beginner)
Assigning an OnClickListener() via an anonymous class. (Intermediate)
Activity wide interface method using the switch statement. (not-"Pro")
Here's the link to my example if you want to follow along:
Using the onClick attribute of the Button. (Beginner)
Buttons have an onClick attribute that is found within the .xml file:
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="goToAnActivity"
android:text="to an activity" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="goToAnotherActivity"
android:text="to another activity" />
In Java class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
}
public void goToAnActivity(View view) {
Intent intent = new Intent(this, AnActivity.class);
startActivity(intent);
}
public void goToAnotherActivity(View view) {
Intent intent = new Intent(this, AnotherActivity.class);
startActivity(intent);
}
Advantage: Easy to make on the fly, modular, and can easily set multiple onClicks to the same intent.
Disadvantage: Difficult readability when reviewing.
Assigning an OnClickListener() via an anonymous class. (Intermediate)
This is when you set a separate setOnClickListener() to each button and override each onClick() with its own intent.
In Java class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
Button button1 = (Button) findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(view.getContext(), AnActivity.class);
view.getContext().startActivity(intent);}
});
Button button2 = (Button) findViewById(R.id.button2);
button2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(view.getContext(), AnotherActivity.class);
view.getContext().startActivity(intent);}
});
Advantage: Easy to make on the fly.
Disadvantage: There will be a lot of anonymous classes which will make readability difficult when reviewing.
Activity wide interface method using the switch statement. (not-"Pro")
This is when you use a switch statement for your buttons within the onClick() method to manage all the Activity's buttons.
In Java class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
Button button1 = (Button) findViewById(R.id.button1);
Button button2 = (Button) findViewById(R.id.button2);
button1.setOnClickListener(this);
button2.setOnClickListener(this);
}
#Override
public void onClick(View view) {
switch (view.getId()){
case R.id.button1:
Intent intent1 = new Intent(this, AnActivity.class);
startActivity(intent1);
break;
case R.id.button2:
Intent intent2 = new Intent(this, AnotherActivity.class);
startActivity(intent2);
break;
default:
break;
}
Advantage: Easy button management because all button intents are registered in a single onClick() method
For the second part of the question, passing data, please see How do I pass data between Activities in Android application?
Edit: not-"Pro"
Create an intent to a ViewPerson activity and pass the PersonID (for a database lookup, for example).
Intent i = new Intent(getBaseContext(), ViewPerson.class);
i.putExtra("PersonID", personID);
startActivity(i);
Then in ViewPerson Activity, you can get the bundle of extra data, make sure it isn't null (in case if you sometimes don't pass data), then get the data.
Bundle extras = getIntent().getExtras();
if(extras !=null)
{
personID = extras.getString("PersonID");
}
Now if you need to share data between two Activities, you can also have a Global Singleton.
public class YourApplication extends Application
{
public SomeDataClass data = new SomeDataClass();
}
Then call it in any activity by:
YourApplication appState = ((YourApplication)this.getApplication());
appState.data.CallSomeFunctionHere(); // Do whatever you need to with data here. Could be setter/getter or some other type of logic
When user clicks on the button, directly inside the XML like that:
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextButton"
android:onClick="buttonClickFunction"/>
Using the attribute android:onClick we declare the method name that has to be present on the parent activity. So I have to create this method inside our activity like that:
public void buttonClickFunction(View v)
{
Intent intent = new Intent(getApplicationContext(), Your_Next_Activity.class);
startActivity(intent);
}
Intent iinent= new Intent(Homeactivity.this,secondactivity.class);
startActivity(iinent);
Intent in = new Intent(getApplicationContext(),SecondaryScreen.class);
startActivity(in);
This is an explicit intent to start secondscreen activity.
Emmanuel,
I think the extra info should be put before starting the activity otherwise the data won't be available yet if you're accessing it in the onCreate method of NextActivity.
Intent myIntent = new Intent(CurrentActivity.this, NextActivity.class);
myIntent.putExtra("key", value);
CurrentActivity.this.startActivity(myIntent);
Try this simple method.
startActivity(new Intent(MainActivity.this, SecondActivity.class));
From the sending Activity try the following code
//EXTRA_MESSAGE is our key and it's value is 'packagename.MESSAGE'
public static final String EXTRA_MESSAGE = "packageName.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
....
//Here we declare our send button
Button sendButton = (Button) findViewById(R.id.send_button);
sendButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//declare our intent object which takes two parameters, the context and the new activity name
// the name of the receiving activity is declared in the Intent Constructor
Intent intent = new Intent(getApplicationContext(), NameOfReceivingActivity.class);
String sendMessage = "hello world"
//put the text inside the intent and send it to another Activity
intent.putExtra(EXTRA_MESSAGE, sendMessage);
//start the activity
startActivity(intent);
}
From the receiving Activity try the following code:
protected void onCreate(Bundle savedInstanceState) {
//use the getIntent()method to receive the data from another activity
Intent intent = getIntent();
//extract the string, with the getStringExtra method
String message = intent.getStringExtra(NewActivityName.EXTRA_MESSAGE);
Then just add the following code to the AndroidManifest.xml file
android:name="packagename.NameOfTheReceivingActivity"
android:label="Title of the Activity"
android:parentActivityName="packagename.NameOfSendingActivity"
Intent i = new Intent(firstactivity.this, secondactivity.class);
startActivity(i);
Kotlin
First Activity
startActivity(Intent(this, SecondActivity::class.java)
.putExtra("key", "value"))
Second Activity
val value = getIntent().getStringExtra("key")
Suggestion
Always put keys in constant file for more managed way.
companion object {
val PUT_EXTRA_USER = "user"
}
startActivity(Intent(this, SecondActivity::class.java)
.putExtra(PUT_EXTRA_USER, "value"))
Starting an activity from another activity is very common scenario among android applications.
To start an activity you need an Intent object.
How to create Intent Objects?
An intent object takes two parameter in its constructor
Context
Name of the activity to be started. (or full package name)
Example:
So for example,if you have two activities, say HomeActivity and DetailActivity and you want to start DetailActivity from HomeActivity (HomeActivity-->DetailActivity).
Here is the code snippet which shows how to start DetailActivity from
HomeActivity.
Intent i = new Intent(HomeActivity.this,DetailActivity.class);
startActivity(i);
And you are done.
Coming back to button click part.
Button button = (Button) findViewById(R.id.someid);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent i = new Intent(HomeActivity.this,DetailActivity.class);
startActivity(i);
}
});
The way to start new activities is to broadcast an intent, and there is a specific kind of intent that you can use to pass data from one activity to another. My recommendation is that you check out the Android developer docs related to intents; it's a wealth of info on the subject, and has examples too.
You can try this code:
Intent myIntent = new Intent();
FirstActivity.this.SecondActivity(myIntent);
Start another activity from this activity and u can pass parameters via Bundle Object also.
Intent intent = new Intent(getBaseContext(), YourActivity.class);
intent.putExtra("USER_NAME", "xyz#gmail.com");
startActivity(intent);
Retrive data in another activity (YourActivity)
String s = getIntent().getStringExtra("USER_NAME");
// In Kotlin , you can do as
/* In First Activity, let in activity layout there is button which has id as button.
Suppose I have to pass data as String type from one activity to another */
val btn = findViewById<Button>(R.id.button)
btn.setOnClickListener {
val intent = Intent(baseContext, SecondActivity::class.java).apply {
putExtra("KEY", data)
}
startActivity(intent)
}
// In Second Activity, you can get data from another activity as
val name = intent.getStringExtra("KEY")
/* Suppose you have to pass a Custom Object then it should be Parcelable.
let there is class Collage type which I have to pass from one activity to another
*/
import android.os.Parcelable
import kotlinx.android.parcel.Parcelize
#Parcelize
class Collage(val name: String, val mobile: String, val email: String) : Parcelable
/* Activity First , let here data is Collage type. which I have to pass to another activity. */
val btn = findViewById<Button>(R.id.button)
btn.setOnClickListener {
val intent = Intent(baseContext, SecondActivity::class.java).apply {
putExtra("KEY", data)
}
startActivity(intent)
}
// then from second Activity we will get as
val item = intent.extras?.getParcelable<Collage>("KEY")
Button button = findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(SplashActivity.this,HomeActivity.class);
startActivity(intent);
}
});
Implement the View.OnClickListener interface and override the onClick method.
ImageView btnSearch;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_search1);
ImageView btnSearch = (ImageView) findViewById(R.id.btnSearch);
btnSearch.setOnClickListener(this);
}
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnSearch: {
Intent intent = new Intent(Search.this,SearchFeedActivity.class);
startActivity(intent);
break;
}
Although proper answers have been already provided but I am here for searching the answer in language Kotlin. This Question is not about language specific so I am adding the code to accomplish this task in Kotlin language.
Here is how you do this in Kotlin for andorid
testActivityBtn1.setOnClickListener{
val intent = Intent(applicationContext,MainActivity::class.java)
startActivity(intent)
}
The Most simple way to open activity on button click is:
Create two activities under the res folder, add a button to the first activity and give a name to onclick function.
There should be two java files for each activity.
Below is the code:
MainActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.content.Intent;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void goToAnotherActivity(View view) {
Intent intent = new Intent(this, SecondActivity.class);
startActivity(intent);
}
}
SecondActivity.java
package com.example.myapplication;
import android.app.Activity;
import android.os.Bundle;
public class SecondActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity1);
}
}
AndroidManifest.xml(Just add this block of code to the existing)
</activity>
<activity android:name=".SecondActivity">
</activity>
Take Button in xml first.
<Button
android:id="#+id/pre"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#mipmap/ic_launcher"
android:text="Your Text"
/>
Make listner of button.
pre.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, SecondActivity.class);
startActivity(intent);
}
});
When button is clicked:
loginBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent= new Intent(getApplicationContext(), NextActivity.class);
intent.putExtra("data", value); //pass data
startActivity(intent);
}
});
To received the extra data from NextActivity.class :
Bundle extra = getIntent().getExtras();
if (extra != null){
String str = (String) extra.get("data"); // get a object
}
Write the code in your first activity .
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(MainActivity.this, SecondAcitvity.class);
//You can use String ,arraylist ,integer ,float and all data type.
intent.putExtra("Key","value");
startActivity(intent);
finish();
}
});
In secondActivity.class
String name = getIntent().getStringExtra("Key");
Place button widget in xml like below
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
/>
After that initialise and handle on click listener in Activity like below ..
In Activity On Create method :
Button button =(Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new
Intent(CurrentActivity.this,DesiredActivity.class);
startActivity(intent);
}
});
An old question but if the goal is to switch displayed pages, I just have one activity and call setContentView() when I want to switch pages (usually in response to user clicking on a button). This allows me to simply call from one page's contents to another. No Intent insanity of extras parcels bundles and whatever trying to pass data back and forth.
I make a bunch of pages in res/layout as usual but don't make an activity for each. Just use setContentView() to switch them as needed.
So my one-and-only onCreate() has:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LayoutInflater layoutInflater = getLayoutInflater();
final View mainPage = layoutInflater.inflate(R.layout.activity_main, null);
setContentView (mainPage);
Button openMenuButton = findViewById(R.id.openMenuButton);
final View menuPage = layoutInflatter.inflate(R.layout.menu_page, null);
Button someMenuButton = menuPage.findViewById(R.id.someMenuButton);
openMenuButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
setContentView(menuPage);
}
});
someMenuButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
do-something-interesting;
setContentView(mainPage);
}
}
}
If you want the Back button to go back through your internal pages before exiting the app, just wrap setContentView() to save pages in a little Stack of pages, and pop those pages in onBackPressed() handler.
your button xml:
<Button
android:id="#+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="jump to activity b"
/>
Mainactivity.java:
Button btn=findViewVyId(R.id.btn);
btn.setOnClickListener(btnclick);
btnclick.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent();
intent.setClass(Mainactivity.this,b.class);
startActivity(intent);
}
});
imageView.setOnClickListener(v -> {
// your code here
});
Kotlin 2022
The simplest way:
val a = Intent(this.context, BarcodeActivity::class.java)
a.putExtra("barcode", barcode)
startActivity(a)
and in the other side (BarcodeActivity in my case):
val intent: Intent = intent
var data = intent.getStringExtra("barcode")
Read more here