I'm trying to send data from an overlay to other activity with this class
public class Capas extends ItemizedOverlay<OverlayItem>
{
MapView Map;
private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
#SuppressWarnings("unused")
private Context mContext;
public Capas(Drawable defaultMarker, Context context)
{
super(boundCenterBottom(defaultMarker));
mContext = context;
}
#Override
public boolean onTouchEvent(MotionEvent event, MapView mapView)
{
if (event.getAction() == 1) {
GeoPoint puntoTocado = mapView.getProjection().fromPixels((int) event.getX(),(int) event.getY());
Intent nuevoLugar=new Intent(Capas.this,editarLugar.class);
nuevoLugar.putExtra("latitud",puntoTocado.getLatitudeE6());
nuevoLugar.putExtra("longitud",puntoTocado.getLongitudeE6());
StartActivity()
}
return false;
}
}
But this return me the next error The constructor Intent(Capas, Class) is undefined.
I try with Intent nuevoLugar=new Intent(Capas.class,editarLugar.class); Intent nuevoLugar=new Intent(this,editarLugar.class); but anoone works
In this case this should work:
Intent nuevoLugar = new Intent(mContext, editarLugar.class);
Provided that editarLugar extends Activity and is declared in AndroidManifest.xml.
And to start the activity:
mContext.startActivity(nuevoLugar);
the first argument should be a Context. please try Intent nuevoLugar=new Intent(mContext,editarLugar.class);
To create a a new intent you need to get access to a Context instance. ItemizedOverlay doesn't extend from it.
You have you initialize the intent like this:
Intent nuevoLugar=new Intent(mContext, editarLugar.class);
You need to make sure that editarLugar is an Activity.
But also, you need access to the activity. Since I think we can assume that you are creating it from an Activity you can launch it like this:
if(mContext instanceof Activity) {
((Activity)mContext).startActivity(nuevoLugar);
}
My bad, you can just call:
mContext.startActivity(nuevoLugar);
Related
Before you flame me:
I know there are uncountable tutorials out there, and I know myself how to pass data to another ACtivity, just like that.
In my case that's diffrent tho. "Usually" data is passed to another activity through Intents, Bundles ecc and the other Activity is started.
Here's my case:
I have an Item with 4 parameters (Image, String,String, int)
In an AdapterClass I have a PopUpView which retakes those 4 parameters.
What I'd like to achieve is the following:
With the click of a button, the 4th parameter, the int should be sent to the Main activity and inserted in a textView inside the MainActivity, without (here's the main diffrence between this and the other questions)launching the Main Activity.
How can this be done?
TIA.
use BroadcastReceiver to send that 4th int to MainActivity
in PopupView do these:
Intent intent = new Intent("SOMEACTION");
intent.putExtra("4th_int", value);
activity.sendBroadcast(intent);'
//In MainActivity:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
IntentFilter filter = new IntentFilter("SOMEACTION");
this.registerReceiver(mReceiver , filter);
}
#Override
public void onDestroy() {
super.onDestroy();
this.unregisterReceiver(this.mReceiver );
}
private BroadcastReceiver mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction() == "SOMEACTION") {
// retrieve the 4th int value and update something in MainActivity
}
}
};
I'm stuck at this point:
private BroadcastReceiver mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
String number = bundle.getString("Time");
GameTime.setText("" +number + " hours");
}
};
In another Activity, when a Button is pressed, the MainActivity get's an int.
Whenever I open the Activity, I cannot see the GameTime TextView with the number variable in it.
I know that the OnReceive method works, beacause I had put a toast in it, and I could see the toast after sending the int from the other Activity.
How can I keep the changes made to the TextView while changing Activities?
Thank you.
One way:
Define an interface in your activity & Implement the interface inside your activity and pass its reference to the other class and call that reference whenever you need.
Example:
a) Create an interface
public interface MyBroadcastListener{
public void doSomething(String result);
}
b) Initialize BroadCastReceiver
public class TestNotifAlarm extends BroadcastReceiver {
private MyBroadcastListener listener;
#Override
public void onReceive(Context context, Intent intent) {
listener = (MyBroadcastListener)context;
listener.doSomething("Some Result");
}
}
c) Implement the interface in Activity
public YourActivity extends AppCompatActivity implements MyBroadcastListener{
// Your Activity code
public void updateTheTextView(String t) {
TextView textView = (TextView) findViewById(R.id.textView);
textView.setText(t);
}
#Override
public void doSomething(String result){
updateTheTextView(result); // Calling method from Interface
}
}
Another Way :
a) Put a Receiver inside your Activity class
BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
textView.setText(intent.getStringExtra("extra"));
}
};
b) Register BroadCastReceiver
registerReceiver(broadcastReceiver , new IntentFilter("trigger_broadcust"));
c) Call sendBroadcast
Intent intent = new Intent("trigger_broadcust");
intent.putStringExtra("extra", "data");
sendBroadcast(intent);
In my project I have some buttons, with their own View.OnClickListener.
What I want is to "externalize" all this onClickListener into a java calss that implements the interface, and handle all the click events, here.
But I found a problem, that I don't know how to fix it.
One of the buttons launch a setResult(RESULT_OK, startChatIntent) and finish(), but thismethods inside the class, are marked as: Cannot be resolved as method.
This is the class : (I take out the other buttons functionalities, that works OK, to make it more clear)
public class startCircuitListener implements View.OnClickListener {
private int mChatType;
private String mGroupName;
private String mNickName;
private String mMessage;
private ArrayList<String> mGroupEmails;
private Context context;
public startCircuitListener(int mChatType, String mGroupName, String mNickName, String mMessage, ArrayList<String> mGroupEmails, Context context) {
this.mChatType = mChatType;
this.mGroupName = mGroupName;
this.mNickName = mNickName;
this.mMessage = mMessage;
this.mGroupEmails = mGroupEmails;
this.context = context;
}
#Override
public void onClick(View v) {
Intent startChatIntent = new Intent();
startChatIntent.putExtra("chatRoom", mGroupName);
startChatIntent.putExtra("chatServer", HelperVariables.CONFERENCE_SERVER_NAME);
startChatIntent.putExtra("nickname", mNickName);
startChatIntent.putExtra("Individual_Group", 0);
startChatIntent.putExtra("MessageToSend", mMessage);
startChatIntent.putExtra("Invitations", mGroupEmails);
setResult(RESULT_OK, startChatIntent);
finish();
}
}
How can I make work setResult and finish()?
You have to create your listener instance with the current Activity instance, and store it as a member of startCircuitListener.
Then call this.myActivity.setResult(RESULT_OK, startChatIntent);. Same thing for finish();
I have a menu and 5 activities. To avoid repeating the menu code, I have created a public class and call it in every activity:
Testclass testclass = new Testclass(Main.this);
...but unfortunately I can't use startActivity() in the class. This is my class code:
public class Testclass extends Activity {
public Testclass(Activity cc) {
Intent intent = new Intent(cc,Next.class);
startActivity(intent);
}
}
Try this and tell me if it helped you.
public class Testclass extends Activity {
public Testclass(Activity cc) {
final Context context = Testclass.this.getContext();
Intent intent = new Intent(context , Next.class);
context.startActivity(intent);
}
}
You misunderstood the concept of an Activity and its life cycle. You DON'T instantiate the Activity, the Activity has callback mechanisms (onCreate, onResume, etc.) that tell you exactly what to do. You never ever have to call new Activity().
The fact that you're doing
Testclass testclass = new Testclass(Main.this); shows that you have a misunderstanding of this concept: http://developer.android.com/training/basics/activity-lifecycle/index.html
To fix your error, read the docs and then it will be clear what is wrong with your approach.
Hint: Your Testclass already IS an Activity, because you inherit from Activity.
And next time please provide the whole error log to your problem, so it can give the whole picture of what can be wrong with your code.
Why not use this code?
startActivity(new Intent(Main.this, Next.class));
// "Main" is your current Activity
// "Next" is your next Activity to be opened.
I think, it's very simple to use without create a new public class. Please compare your codes with my code above, only one line.
I think you don't use the correct Context to start the Intent.
Instead try
{
public Testclass() {
Intent intent = new Intent(this,Next.class);
startActivity(intent);
}
}
if the this doesn't work either, try getApplicationContext() instead.
#you can used Weak Reference Objects to store Context of Activity class#
##in activity class##
public class Activity extends AppCompatActivity implements View.OnClickListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view);
findViewById(R.id.toNext).setOnClickListener(this);
}
#Override
public void onClick(View v) {
Testclass thread = new Testclass(Activity.this,v);
new Thread(thread).start();
}
}
}
// in sub class
public class Testclass extends Activity implements Runnable {
View landingPage;
private Activity activity;
public Testclass (Activity activity, View landingPage){
WeakReference<Activity> ActivityWeakReference = new WeakReference<>(Activity);
this.landingPage = landingPage;
this.activity = activityWeakReference.get();
}
#Override
public void run() {
Intent activityIntent = new Intent(activity, Next.class);
activityIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
runOnUiThread(new Runnable() {
#Override
public void run() {
switch (landingPage.getId())
{
case R.id.Next.class:
activity.finish();
activity.startActivity(activityIntent);
break;
}
}
});
}
}
I have an easy question.
I have declared text view in main activity, and created it from XML (findViewById). I would like to pass this value to a subclass of broadcast receiver. Following is my Broadcast constructor:
public Broadcast(TextView text_dBm) {
this.text_dBm = text_dBm;
}
In my main activity I create a new broadcast object and pass my textview value inside, like this:
new Broadcast(text_dBm);
But I'm still getting null pointer exception on my text_dBm. Is there anyway (besides static methods) to pass values between activites and broadcast receiver?
Oh and yes. My broadcast receiver is registered programmatically (in service), and its running perfectly.
Thank you for your time!
P.S: I already checked some threads here in SO, but i didn't find an answer:
How to pass value from an activity in an broadcast receiver?
Main activity class:
public class MainActivity extends Activity {
TextView text_dBm, text_time, text_rssi;
Intent startServiceFromActivity;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
text_dBm = (TextView) findViewById(R.id.textView_dBm);
new Broadcast(text_dBm);
startServiceFromActivity = new Intent(this, WifiService.class);
startService(startServiceFromActivity);
}
}
Broadcast receiver class:
public class Broadcast extends BroadcastReceiver {
WifiInfo wifiInfo;
WifiManager wifiManager_service;
TextView text_dBm;
public Broadcast(WifiManager wifiManager_service) {
this.wifiManager_service = wifiManager_service;
}
public Broadcast(TextView text_dBm) {
this.text_dBm = text_dBm;
}
#Override
public void onReceive(Context context, Intent intent) {
Log.d("RECEIVER", "Receiver running"); // LOG
text_dBm.setText("textview"); // nullpointerexception
}
}
You can't pass around views using Intents. To do what you want to do, you will need your broadcast receiver to be an inner class of your activity. The receiver should be registered when activity is started and unregistered when activity is stopped. Else you will leak memory. That means that you will only be able to receive your messages when actually on the activity screen itself.
If you need to be able to receive broadcasts outside the activity, you will need to:
register your receiver in the manifest for a given action (or in a service, but don't forget to unregister it)
start the activity and pass the message to show in the textview using an intent extra
when the activity starts, check if the intent contains anything to show in the textview and do the necessary
From your comment:
Create the receiver as an inner class of the activity (not a static one so it can access the activity's TextView instance)
register the receiver in onStart
unregister the receiver in onStop
In the onReceive method of your receiver do: textView.setText(intent.getStringExtra("dbm"));
Service sends the broadcast by passing an intent extra called "dbm" and containing the text you want to display
-
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
dbmView = (TextView) findViewById(R.id.textView_dBm);
}
#Override
protected void onStart() {
super.onStart();
IntentFilter intentFilter = new IntentFilter("com.example.broadcasts.DBM_UPDATE");
registerReceiver(receiver, intentFilter);
}
#Override
protected void onStop() {
unregisterReceiver(receiver);
super.onStop();
}
private TextView dbmView;
private BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
dbmView.setText(intent.getStringExtra("dbm"));
}
}
}
In the service:
Intent i = new Intent("com.example.broadcasts.DBM_UPDATE");
i.putExtra("dbm", "it works!");
sendBroadcast(i);
Pass data Through intent
Activity -
Intent i = new Intent(Activity.this, Broadcast.class);
Bundle b = new Bundle();
b.putString("key", "value");
i.putExtras(b);
startActivity(i);
In your broadcast receiver class onReceive method
#Override
public void onReceive(Context context, Intent intent)
{
String result = intent.getString("key");
// your method
}