I have two classes a MainActivity.class and a IntentsUtils.class.
Here is my IntentsUtils.class:
public class IntentsUtils
{
public void invokeWebBrowser(Activity activity)
{
String url = "http://snipt.net/Martin/android-intent-usage/";
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(url));
activity.startActivity(intent);
}
}
If I wanted to run invokeWebBrowser() from my MainActivity.class, what would be the best method?
Thanks.
Button button = (Button) findViewById(R.id.launch_br_btn);
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick() {
IntentUtils.invokeWebBrowser(MainActivity.this);
}
})
put this to your onCreate() method of MainActivity.
Related
I've got little problem with implementing asynctask for my class project.
"PART_OF_URL?title="+tytul+"&author="+autor+"&date="+dataSt+"&username="+imieSt
so this is whole string that should be executed, it works "perfectly" fine like this:
Intent i = new Intent(Intent.ACTION_VIEW);
i.setData(Uri.parse("PART_OF_URL?title="+tytul+"&author="+autor+"&date="+dataSt+"&username="+imieSt));
startActivity(i);
Which sends data to PART_OF_URL website that display order list
but instead of that it should be done in asynctask.
Here is whole activity code that handle sending data:
public class Zamowienie extends AppCompatActivity {
TextView tytulzamowieniaTV;
EditText data;
EditText imie;
Button zamawiaj;
Button anuluj;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_zamowienie);
tytulzamowieniaTV=findViewById(R.id.tytulZamwowienia);
data=findViewById(R.id.data);
imie=findViewById(R.id.imie);
zamawiaj=findViewById(R.id.zamawiaj);
anuluj=findViewById(R.id.anuluj);
tytulzamowieniaTV.setText(getIntent().getStringExtra("Tytul"));
String tytul=getIntent().getStringExtra("Tytul");
String autor=getIntent().getStringExtra("Autor");
wyslijZamowienie(tytul,autor);
}
public void wyslijZamowienie(String tytul,String autor){
zamawiaj.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String dataSt=data.getText().toString();
String imieSt=imie.getText().toString();
Intent i = new Intent(Intent.ACTION_VIEW);
i.setData(Uri.parse("PART_OF_URL?title="+tytul+"&author="+autor+"&date="+dataSt+"&username="+imieSt));
startActivity(i);
}
});
}
}
Understanding asynctask is problematic for me so any help is appreciated.
I want to define callback for a Notebook program that way after note saved in EditActivity,in Main Activity Update list of notes,But This does not happen.
EditActivity:
public interface OnClickDoneListener{
void onClickDone();
}
public void setOnClickDoneListener(OnClickDoneListener onClickDoneListener){
this.onClickDoneListener=onClickDoneListener;
}
btnDone.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (extras != null) {
myDatabase.updateRow(id, txtTitle.getText().toString(), txtDesc.getText().toString());
NoteModel noteModel = new NoteModel();
noteModel.setTitle(txtTitle.getText().toString());
noteModel.setDesc(txtDesc.getText().toString());
Intent intent = new Intent(EditActivity.this, MainActivity.class);
startActivity(intent);
onClickDoneListener.onClickDone();
} else {
Done();
}
}
});
Main Activity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
setupViews();
getDataFromDB();
recyclerView.setAdapter(new NoteAdapter(MainActivity.this,dataList));
noteAdapter = new NoteAdapter(MainActivity.this,dataList);
recyclerView.setAdapter(noteAdapter);
fabAdd = (FloatingActionButton)findViewById(R.id.fab_main_add) ;
EditActivity editActivity = new EditActivity();
editActivity.setOnClickDoneListener(new EditActivity.OnClickDoneListener() {
#Override
public void onClickDone() {
noteAdapter.notifyDataSetChanged();
}
});
please help me.
My English is poor,sorry for it.
You want your data to be updated when the MainActivity is shown, right ?
You just have to call your getDataFromDB part in onResume() instead of onCreate()
EditActivity editActivity = new EditActivity();
editActivity.setOnClickDoneListener(new EditActivity.OnClickDoneListener() {
#Override
public void onClickDone() {
noteAdapter.notifyDataSetChanged();
}
});
What you are doing here is setting the value of OnClickDoneListener in a new instance of EditActivity that you will never use. Because when you use new Intent(MainActivity.this, EditActivity.class) to start the EditActivity it will create a new instance of EditActivity and your interface would be null.
I suggest you use android's Broadcast Receiver instead of a callback in this case. All you have to do is:
In MainActivity: You will need to instantiate a broadcast receiver. You need to register it onCreate or onStart and unregister it onStop or onDestory.
In EditAcitivity: You send a broadcast whenever you want to notify your MainActivity to update the list.
Check out this example:
https://riptutorial.com/android/example/18305/communicate-two-activities-through-custom-broadcast-receiver
I have three Activities. MainActivity,ActivityB and ActivityC. In activity A and B there are two buttons source and destination in both activities. in Activity C there is a list of data. when button is clicked (either Source or destination) from activity A and B. both Activities are calling Activity C
code for Activity A is following
public class MainActivity extends Activity {
TextView source,destination;
Button sendSource,sendDestination,btnTob;
String src,des,activity,checksrc,checkdes;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
source=(TextView)findViewById(R.id.tv_rcvDataA);
destination=(TextView)findViewById(R.id.tv_rcvDataAa);
sendSource=(Button)findViewById(R.id.btn_sendA);
sendDestination=(Button)findViewById(R.id.btn_sendAa);
btnTob=(Button)findViewById(R.id.btn_toB);
sendSource.setText("source");
sendDestination.setText("destination");
src=sendSource.getText().toString();
des=sendDestination.getText().toString();
activity=getClass().getSimpleName();
sendSource.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent send= new Intent(MainActivity.this,ActivityC.class);
send.putExtra("source",src);
send.putExtra("Activity",activity);
startActivity(send);
}
});
sendDestination.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent senda= new Intent(MainActivity.this,ActivityC.class);
senda.putExtra("destination",des);
senda.putExtra("Activity",activity);
startActivity(senda);
}
});
btnTob.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent movetoB= new Intent(MainActivity.this,ActivityB.class);
startActivity(movetoB);
finish();
}
}); }}
and code for Activity B is
public class ActivityB extends Activity {
TextView sourceB,destinationB;
Button sendSourceB,sendDestinationB;
String src,des,activity,checksrc,checkdes;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_b);
sourceB=(TextView)findViewById(R.id.tv_rcvDataB);
destinationB=(TextView)findViewById(R.id.tv_rcvDataBa);
sendSourceB=(Button)findViewById(R.id.btn_sendB);
sendDestinationB=(Button)findViewById(R.id.btn_sendDataBa);
activity=getClass().getSimpleName();
sendDestinationB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent senda= new Intent(ActivityB.this,ActivityC.class);
senda.putExtra("destination",src);
senda.putExtra("Activity",activity);
startActivity(senda);
}
});
sendSourceB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent send= new Intent(ActivityB.this,ActivityC.class);
send.putExtra("source",src);
send.putExtra("Activity",activity);
startActivity(send);
}
});}}
now how to check in activityC which activity is calling this activity and which buttonclicklistener is calling the intent
You need to send the value for determine what value and what activity via Intent.putExtra(). Please be remember that you need to set the key as the first parameter for Intent.putExtra(), like
intent.putExtra(THIS_IS_THE_KEY, THIS_IS_YOUR_VALUE);
You need to create something like this:
// This is the key for your putExtra
// you need to create this as global variable.
public static final String FROM_KEY = "FROM";
public static final String ACTIVITY_KEY = "ACTIVITY";
public static final boolean IS_FROM_SOURCE = true;
// This is a sample to send data to Activity C
// where the activity caller is B and from source
Intent senda= new Intent(ActivityB.this,ActivityC.class);
senda.putExtra(FROM_KEY, IS_FROM_SOURCE);
senda.putExtra(ACTIVITY_KEY,"activity_a");
Then in your Activity C, you need to receive the Intent Extra.
You can get the value in Activity onCreate(), something like this:
Bundle extras = getIntent().getExtras();
boolean from = extras.getBoolean(FROM_KEY);
String act = extras.getString(ACTIVITY_KEY);
// do something here if from activity a
if(act.equals("activity_a")) {
if(IS_FROM_SOURCE) {
// do something if from source
} else {
// do something if from destination.
}
} else { // if from activity a
if(IS_FROM_SOURCE) {
// do something if from source
} else {
// do something if from destination.
}
}
In onCreate or anytime after that method is called in Activity-C, you should do the following:
Intent intent = getIntent();
if (intent != null) {
String activity = intent.getStringExtra("Activity");
String src = intent.getStringExtra("source");
// Do something with those values
}
I will make anonym function onClick for new widget. I load variable data from res/raw. But i need some ID for load it. I use getResources().getIdentifier()
It looks like this:
TextView ans = new TextView(this);
String exm = "demo";
ans.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(FullscreenActivity.this, Video.class);
intent.putExtra("ex", getResources().getIdentifier( exm,"raw", getPackageName()));
startActivity(intent);
}
}
);
I have error about variable non inner class variable. But i can't final it - it will be variable. How can i send my variable in new Object OnClickListener and function onClick ?
have it as a class variable
public class MyActivity extends Activity {
String exm = "demo";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ans.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(FullscreenActivity.this, Video.class);
intent.putExtra("ex", getResources().getIdentifier( exm,"raw", getPackageName()));
startActivity(intent);
}
}
);
}
}
The easiest way is to make it a member variable of your containing Activity.
I abstract my model like this:first there is a class UserInfo which holds user information:
public class UserInfo extends Application{
private int userid;
public void setUserId(int id)
{
userid=id;
}
public int getUserId()
{
return userid;
}
}
Then in MainActivity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
userinfo=(UserInfo)getApplication();
userinfo.setUserId(1354);
....
Intent intent=new Intent(MainActivity.this,VoteActivity.class);
startActivity(intent);
}
public
#Override void onResume()
{
super.onResume();
TextView text=(TextView)MainActivity.this.findViewById(R.id.usernameText);
text.setText(userinfo.getUserId()+" ");
}
And in VoteActivity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_vote);
userinfo=(UserInfo)getApplication();
Button back=(Button)findViewById(R.id.backButton);
back.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View arg0) {
userinfo.setUserId(-100);
Intent intent=new Intent(VoteActivity.this,MainActivity.class);
startActivity(intent);
}});
}
The result is: when MainActivity first run, userid in UserInfo is 1354 ; And when VoteActivity first run, userid in UserInfo is 1354 too.However when back to MainActivity from VoteAcitivy userid remains 1354 which should be -100.What is wrong with this use of Application context?
You're starting a new activity in your onClick method :
Intent intent=new Intent(VoteActivity.this,MainActivity.class);
startActivity(intent);
And you direct set your id in the MainActivity :
userinfo.setUserId(1354);
That's why you get (1354). You should call finish in your on click (instead of starting the MainActivity).
The activity's stack look like this : MainActivity - VoteActivity - MainActivity and I think you want it to look like this : MainActivity after pressed on your Button
#Override
public void onClick(View arg0) {
userinfo.setUserId(-100);
finish();
}});
How you do you get back for your MainActivity? Pressing the device's back button or clicking on your button? If you press the device's back button your onClickListener won't be called, so that's why id remains the same.
#Override
public void onClick(View arg0) {
userinfo.setUserId(-100);
Intent intent=new Intent(VoteActivity.this,MainActivity.class);
startActivity(intent);
}});
when you click on your back button you restart MainActivity. The MainActivity onCreate will be excuted again. Is MainActivity flagged as singleInstance?