I'm looking to randomly start activities in android studio without repetition. I'd like to be able to start an activity randomly by clicking a button and in an 'if' statement. Whoever can help out that would be fantastic! Thank you.
ArrayList<Class> activities = new ArrayList<>();
#Override
public void onCreate(Bundle savedInstanceState) {
//your codes...
activities.add(History.class);
activities.add(Bookmark.class);
activities.add(Themes.class);
//your codes
}
public void openActivity(Class class_) {
Intent intent = new Intent(this, class_);
startActivity(intent);
}
public void openRandomActivity(){
Class that = activities.get(new Random().nextInt(activities.size()));
activities.remove(that); // after using, remove from list
openActivity(that);
}
Call openRandomActivity when a user click to button.
Related
There is a link in one activity, after I click on it it opens another activity. I add an enum parameter for the second activity.
#Override
protected void onCreate(Bundle savedInstanceState) {
binding.myLink.setOnClickListener(new View.OnClickListener() {
// ...
#Override
public void onClick(View view) {
Intent intent = new Intent(getActivityContext(), SecondActivity.class);
intent.putExtra(KEY, MyEnum.ENUM_VALUE);
startActivity(intent);
}
});
// ...
}
In onCreate of second activity I read this parameter
#Override
protected void onCreate(Bundle savedInstanceState) {
// ...
// get value
FirstActivity.MyEnum value = (FirstActivity.MyEnum ) getIntent()
.getSerializableExtra(AboutActivity.KEY);
// ...
}
Everything works but in Crashlytics I see that for some users value is null. Second activity is called only from first one and from nowhere else.
Can someone suggest me the scenario with this behavior? When can it happen like this?
I opened my app, opened the second activity and put app to background. After several hours I opened my app from the list of apps and everything is ok. No more ideas when it can happen.
use this :
#Override
public void onClick(View view) {
Intent intent = new Intent(getActivityContext(), SecondActivity.class);
Bundle bundle=new Bundle();
bundle.putSerializable(serializableKEY,yourSerializableClass);
intent.putExtras(KEY, bundle);
startActivity(intent);
}
});
and in second activity :
Bundle bundle=getIntent().getExtras();
yourSerializableClass clazz=(yourSerializableClass)bundle.getSerializable(serializableKEY);
i am working on an app in which, button Onclick dynamically created a button from one activity and button is appeared in another activity.
So, for your button, see the code below. I'm just using SharedPreferences for testing if button has been clicked before or not.
// Inside your onCreate() method of your SecondActivity.java
((Button)findViewById(R.id.activity2_button)).setOnClickListener(new Button.OnClickListener() {
#Override
public void onClick(View v) {
getSharedPreferences("SharedPreferences", Context.MODE_PRIVATE).edit().putBoolean("ShowButton", true).commit(); // put Boolean inside SharedPreferences
Intent main = new Intent(this, FirstActivity.class);
main.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
startActivity(main);
finish();
}
}
And now, the FirstActivity.java code :
public class FirstActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity1_layout);
if (getSharedPreferences("SharedPreferences", Context.MODE_PRIVATE).getBoolean("ShowButton", false))
((Button)findViewById(R.id.activity1_button)).setVisibility(View.VISIBLE);
else
((Button)findViewById(R.id.activity1_button)).setVisibility(View.GONE);
}
}
Test it, and tell me if this works great. Hope it will work for you, Darkball60 :)
Good evening Stack !
I have started to learn Android development as a hobby and I am now trying to develop my first "real" application (I have made already only five simple applications from books).
In this application, I have two buttons that will "create" the same Activity but by using two different objects from the same base class, hence allowing me to customize the behavior of the application depending on the button that was clicked.
However, when I am trying to create the Intent instance, my application crashes.
Here is the code of the base Activity class
public class BaseDictionnaryActivity extends Activity
{
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.basedictionnary);
}
public void onDestroy()
{
super.onDestroy();
}
}
and here is the code that crashes. The line is the one creating the Intent object.
public class DictionnaryActivity extends Activity
{
private BaseDictionnaryActivity jlpt1;
private BaseDictionnaryActivity jlpt2;
private Button btjlpt1 = null;
private Button btjlpt2 = null;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.dictionnary);
jlpt2 = new BaseDictionnaryActivity();
jlpt1 = new BaseDictionnaryActivity();
btJLPT1 = (Button)findViewById(R.id.jlpt1);
btJLPT1.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent myIntent = new Intent(DictionnaryActivity.this,
jlpt1.getClass());
jlpt1.this.startActivity(myIntent);
}
});
btJLPT2 = (Button)findViewById(R.id.jlpt2);
btJLPT2.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent myIntent = new Intent(DictionnaryActivity.this,
jlpt2.getClass());
jlpt2.this.startActivity(myIntent);
}
});
}
public void onDestroy()
{
super.onDestroy();
}
}
Thank you for your help !
Just to make correction,
Intent myIntent = new Intent(DictionnaryActivity.this,
jlpt1.getClass());
In this the second argument must be, your target activity BaseDictionnaryActivity.class
So, it looks something like,
Intent myIntent = new Intent(DictionnaryActivity.this,
BaseDictionnaryActivity.class);
startActivity(myIntent);
Also please make sure there will be entry of BaseDictionnaryActivity in your Application's manifest file,
Which is look like,
<activity android:name=".BaseDictionnaryActivity"
....>
</activity>
Maybe:
Intent myIntent = new Intent(DictionnaryActivity.this,
BaseDictionnaryActivity.class);
startActivity(myIntent);
change this
Intent myIntent = new Intent(DictionnaryActivity.this,
NextActivity.class);
Intent myIntent = new Intent(DictionnaryActivity.this,
jlpt2.class);
^^^^^^^^^^^^
You need to provide next activity .class in second argument of Intent.
Replace jlpt1.getClass() with NameOfClassToBeLaunched.class
Also this is bad practice to create Activity instances in other activities.
Hi I am a total android newbie so my question might seem dumb.
I want to make a program that has two activities, one of them is TinyCalActivity1 and the other is TinyCalActivity2.
My intention was that I can make a button to switch between this activity,
package my.app.tinyCal;
public class TinyCalActivity1 extends Activity {
/** Called when the activity is first created. */
Button myButton;
EditText myEdit;
//Intent i = new Intent(TinyCalActivity1.this, TinyCalActivity2.class);
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myButton = (Button)findViewById(R.id.Next);
myEdit = (EditText)findViewById(R.id.entry);
CharSequence thisNum = "1234565";
myEdit.setText(thisNum);
OnClickListener myListener = new OnClickListener(){
public void onClick(View v){
}
};
myButton.setOnClickListener(myListener);
}
}
and TinyCalActivity2.
However, when I write this line and run in my android AVD, it tells me that there's an error.
Intent i = new Intent(this, TinyCalActivity2.class);
There is no error hint in eclipse and I do not know why.
I create TinyCalActivity2.java as a separate file in the same folder as my TinyCalActivity1.java file. And I have registered TinyCalActivity2 in my AndroidManifest.xml.
I would really appreciate any help!
If you put your code
Intent i = new Intent(this, TinyCalActivity2.class);
in button click event, then this refers to button and not ACTIVITY. Thus, you need to mention it as
Intent i = new Intent(TinyCalActivity1.this, TinyCalActivity2.class);
This may resolve the issue
You can try this way.
myButton.setOnClickListener(new OnClickListener(){
public void onClick(View v){
Intent i = new Intent(this, TinyCalActivity2.class);
finish();
}
};
I'm trying to make an app where you start at a menu, click a button and are brought to a list of items (which I later hope to make clickable). But I can't seem to make it call my next activity. Can anyone help?
Your main class / activity:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Menu Button
Button startNewActivity = (Button)findViewById(R.id.startnew);
startNewActivity.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent newActivityIntent = new Intent(YOUR-CLASS-NAME.this,NewActivity.class);
startActivity(newActivityIntent);
}
});
Your NewActivity Class:
public class NewActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.new);
}
}
Is the question "How do I call the next activity" ?
If so, it's pretty easy - Assuming the Activity you want to call is "SomeActivity", call this:
Intent someActivity = new Intent(getBaseContext(), SomeActivity.class);
startActivity(someActivity);
There's also a "startActivityForResult" method, if you want data back from the Activity you're calling. For reference, the Activity page of the API Documentation can be found here. Good luck!