Is the onUpgrade method of SQLiteOpenHelper ever called? If so, when is it called and by what? Or if it is not called by developers, then why is it there? What should be done in the method I have seen examples where it drops all the tables, but then a comment says that dropping all the tables is NOT what you should do.
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How can i call the onUpgrade Method of the database? Background of my question: I do a backup on the sdcard of the full database. And the user can restore this database. But if in the meantime (between backup and restore) an app update has made changes to the database i get a problem on restoring. The new columns are not there after restoring. So i want to call the onUpgrade method to add all new/changed columns. Or is there a better way for this?
View 1 Replies View RelatedI am running into an issue with the way my asynctasks are executed. Here's the problem code:
firstTask = new background().new FirstTask(context);
if(firstTask.execute().get().toString().equals("1"))
secondTask = new background().new SecondTask(context);
What I'm doing here is creating a new asynctask object, assigning it to firstTask and then executing it. I then want to fire off a separate asynctask when the first one is done and making sure it returns a success value (1 in this case). This works perfectly on Android 2.0 and up. However, I am testing with Android 1.5 and problems start popping up. The code above will run the first asynctask but doInBackground() is never called despite onPreExecute() being called. If I am to execute the first task without the get() method, doInBackground() is called and everything works as expected. Except now I do not have a way to determine if the first task completed successfully so that I can tell the second task to execute. Is it safe to assume that this is a bug with asynctask on Android 1.5? Especially since the API says that the get method has been implemented since API 3. Is there any way to fix this? Or another way to determine that the first task has finished?
I'm getting this error ( in the end of this post) which I guess I understand it's because I'm calling something after releasing it.. but I can't find a wy to work it around.I've tried all combinations.. I've tried: mCamera.setPreviewCallback(null); This class, where the surfaceview is implemented can be accessed by 2 different classes one that doesnt implement surfaceview and other that does the error just shows me when I go from the activity that uses the camera to the activity that also uses camera.I don't know what else to do.
View 4 Replies View RelatedI am new to Android development and have been following the tutorials available on the Android website. I am currently on the section of tutorials for Views, specifically the one for Grid Views: Hello, Grid View Tutorial.I am having trouble understanding how views are made through an adapter. I understand that you must override the getView() method in your adapter class and in this method is where you define how your Views are set up. What I don't understand is where does getView() actually get called? Perhaps I've got the wrong kind of mentality here, but in the code below (the Grid View tutorial) I don't see any calls to getView() (or any other things used in the adapter class such as getCount()).
View 1 Replies View RelatedI'm writing a Tetris application on Android for my bachelor thesis at the University of Hasselt. Currently I have a working Tetris base game, but it just keeps on ticking when the activity gets in the background. I'm trying to fix this by overwriting the onStop()and onRestart()methods.when I press my home button on my device I will go to my home screen and onStop() is called. Because the gamemode is now "PAUSE", the game wil not tick anymore. But now, when I longpress my home button and select my tetris activity again, the activity pops up, but it isn't ticking! This is because the onRestart() is never called when I return to play my application.What is the reason that this method is never called? Am I understanding the activity lifecycle wrong?
View 3 Replies View Relateda service started by a broadcast receiver starts an activity. I want to make it possible for this activity to communicate back to the service. I have chosen to use AIDL to make it possible. Everything seems works good except for bindService() method called in onCreate() of the activity. bindService(), in fact, throws a null pointer exception because onServiceConnected() is never called while onBind() method of the service is. Anyway bindService() returns true.The service is obviously active because it starts the activity.I know that calling an activity from a service could sound strange, but unfortunately this is the only way to have speech recognition in a service.
View 4 Replies View RelatedI'm trying to prevent my application to call the same method twice in the event of a double-click, or if the user presses different buttons quickly, almost at the same time.I have clickable Views, acting as buttons, that call the same method but passing different parameters.Inside this method I'm creating a new Thread, because it queries a web server for the result.The problem is that upon two quick clicks, the method is fired twice, two threads are created, and consequently two new activities are created. That makes my app crash.But this only seems to work on slower phones like the G1, I tried on Nexus and before it set blocked = true, the second request has was granted. So is there any way I can block the method being called if it's already running, or if the thread has started so it wont create a new one.
View 3 Replies View RelatedI was wondering how should I proceed to debug while working with frameworks. Like specifically how can i tell which method is being called when a particular event happens.
View 2 Replies View RelatedI added a BroadCastReceiver to my application.I want to call my inputMethod's method but I can't find a way to access it's instance.but I couldn't find a way to get the the InputMethod instance from the InputMethodManager.Is doing a singleton the only way to access it?
View 1 Replies View RelatedI'm trying to modify the SurfaceView I use for doing a camera preview in order to display an overlaying square. However, the onDraw method of the extended SurfaceView is never called.
View 3 Replies View Relatedi have an app that haves a lot of activitys, all created with ONACTIVITYRESULT.which method is called when i press back key? i need to know it because i have to override/implement code on it
View 2 Replies View RelatedI have some code in the onCreate method an Activity and noticed that it is being called three times. Is it normal behaviour?
View 1 Replies View RelatedIn my android app I call the voice recognition in my onCreate method of my startup activity. I have made it a preference to start up with the voice control or not. However, the app takes about 5-7 seconds to load when voice recognition is on. When it is off, the app starts almost instantly. Below is sample code, I have added Free_Form, max_results 1, and a custom prompt to mine.Why would calling the normal android speech recognition take sooo long to load in my OnCreate method?
View 1 Replies View RelatedI get a SQLiteException if I try to issue an alter statement in the onUpgrade method of SQLiteOpenHelper subclass:
Can't upgrade read-only database from version X to Y: /path/to/db
That makes no sense at all! Where did I go wrong?
I am doing my first app with a database and I am having a little trouble understanding the onUpgrade function. My database has a table with an items and a favorite column so that the user can favorite an item. Most implementations I see simply drop the table and reconstruct it but I don't want to do this. I want to be able to add more items to the table.
When the app is upgraded through the android marketplace does the database know its version number? So could I increment the version number in the code and then export it to the marketplace and when the user boots up the upgraded version for the first time then onUpgrade will be called?
If this is the case my onUpgrade would simply pull from a file and add the database items in. Is this a standard way of doing things or is there a better way of handling this in Android. I am trying to stay as standard as possible.
Every time i increase my database version and push the upgraded app to the users, something weird happens.. For some it works perfectly fine, and some report crashes (including through the Market's reporting system) caused by the lack of table columns i just added in onUpgrade.
If you want to see the method:
http://code.google.com/p/tag-todo-list/source/browse/trunk/Donut/src/com/android/todo/data/ToDoDB.java#136
I can't spot any exceptions that appear in onUpgrade. What i'm currently doing to bypass these problems is intercepting the exceptions where the new fields are invoked for the first time and then calling onUpgrade 'manually', which is kind of dirty.
Also, the app sometimes generates a 'no such table' SQLiteException when accessing the main table (again, only for some users) which is incredibly strange... Does someone know why these things happen? Or can you spot something wrong in my code?
How can I emulate an onUpgrade call for my SQLiteOpenHelper class? I have tried changing the version number in my SQLiteOpenHelper class and versionCode in manifest but onUpgrade is not called. Any idea? I need to check my onUpgrade code before upload it to the market, I don't want my app's users get a buggy upgrade.
View 10 Replies View RelatedI'm trying to override the onBackPressed() method of the ActivityGroup class:
public class MyClass extends ActivityGroup {
@Override
public void onBackPressed() {
// do something
return;
}
but I'm getting the error The method onBackPressed() of type MyClass must override a superclass method. I'm relatively new to Java, I've seen here that people do it and it works for them Why I'm getting this error? I'm writing an app for android 1.5, could the problem be here?
In Eclipse, when I mouse hover over a built-in method, it displays a method definition including stuff like what the method does, input objects, return objects etc. If I have a yellow line (warning) under the method I'm trying to use, I can't get the mouse-over to show the definition. If I try hitting F3, I get a "The Jar of this class file belongs to container "Android 1.6" How do I show the definition of the method I am using when there is a warning?
View 1 Replies View RelatedI am trying to use annotation - method.getAnnotation( ) or method.isAnnotationPresent( ) and it is not working. I am using eclipse emulator for 2.1 OS version with JDK 1.6. Following is information about what I did..................
View 4 Replies View RelatedI created a method called insertTable in a class called Table but i can't use it in my onClick method in the main class :
CODE:.......
I want to do a income.insertTable in the onClick method but eclipse say that i need to create a local variable.
Basically I'm calling the onDraw method like so...
code:...................
You see I'm drawing it on top of a Camera view and the information being drawn is subject to change. I have a listener setup which will update the variables being drawn at the appropriate time but I now want to "refresh" this draw in that listener.
I have two android projects, ProjA requires ProjB (in Eclipse Properties > Java Build Path > Projects > Add > ProjB). Every thing compiles ok in Eclipse, but when I run ProjA I get an error: Could not find method XXX, referenced from method YYY. Where XXX - is the method from ProjB. How can I fix the settings?
View 3 Replies View Relatedthe title say it all. I wanna know a corresponding method in Android/Java that is like the GetTickCount method in C#/C++?
View 1 Replies View RelatedWhy should a static method in java accept only final or non final variables within its method, but not static?
For example I have the following method:
CODE:.................
I was reading through app suggestions and someone mentioned an app called mp3 Download that basically functions like limewire, letting you search and download mp3's to your phone. Does anyone know anything about this app and whether it is good or not? Or have suggestions for a similiar app? It had mixed reviews at appbrain and when I searched here it came up with a bunch of other threads.
View 4 Replies View RelatedI was told by a few friends that the iphone has an app that allows you to hold your phone up to a song that you dont know and it tells you the name.Does android have anything like that?
View 6 Replies View RelatedI've created a simple android game, based on the Lunar Lander sample, and I'm having a problem with handling key events.When the activity starts, the only keys that onKeyDown or onKeyUp get called for are the dpad up/down/left/right keys.Neither the menu, back, or dpad_center keys trigger onKey methods. However, once I've pushed one of the dpad up/down/left/right buttons, pressing the menu, back, or dpad_center keys do trigger these methods. I'm not getting any errors, or any indication of what's going wrong.It's possible that the focus is set wrong - the activity is started from a button on screen, so it could be in touchscreen mode. If that's the case, shouldn't touching the back button get me in to the right focus mode so that I can catch the event?I'm using the emulator from SDK-1.5r3.I have not been able to try this on a real phone yet.
View 4 Replies View RelatedI saw it on the market but forgot to install it. It displays the number of remaining minutes, texts and data left for the month if your on a monthly mobile phone plan.
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