I want to have a class "Utils", that will have several methods used all over my code. For example, I have a top bar with a textview and two ImageButtons that must display different texts and icons on different activities.I created the class Util, but it doesn't extend Activity. The problem is that if it doesn't, findViewById isn't there, can't find stuff etc.
View 1 Replies
I want to pass a class reference to an activity, and then the activity will construct the view according to the content of the class.
How could I implement this function?
I go back and forth about how to name activity classes.Activity seems to imply a verb, like EditContact, for example.But that seems more like what one would call the Intent that triggers EditContact.Should the activity be named ContactEditor instead?
View 2 Replies View RelatedI have a custom view that needs a reference to the activity that created it.Dianne Hackborn said in another thread: >Give your view a reference to the activity (or a Java interface it implements) and call back through that. >Much much MUCH more efficient than sending a broadcast. >See all of the standard view and view subclass callbacks for examples.
View 9 Replies View RelatedI'm building a small Android application, but this is more of a Java question than an android question. Looking through the tutorials there are lines that look like: startService(new Intent(this, MyService.class));
What exactly does the "MyService.class" field represent? Is that just a reference to the class for a template?
I had a bunch of code in an activity that displays a running graph of some external data. As the activity code was getting kind of cluttered, I decided to extract this code and create a GraphView class:
public class GraphView extends LinearLayout {
public GraphView(Context context, AttributeSet attrs) {
super(context, attrs);
LayoutInflater inflater = (LayoutInflater)
context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
inflater.inflate(R.layout.graph_view, this, true);
}
public void start() {
// Perform initialization (bindings, timers, etc) here
}
public void stop() {
// Unbind, destroy timers, } }
Moving stuff into this new LinearLayout-derived class was simple. But there was some lifecycle management code associated with creating and destroying timers and event listeners used by this graph (I didn't want this thing polling in the background if the activity was paused, for example). Coming from a MS Windows background, I kind of expected to find overridable onCreate() and onDestroy() methods or something similar, but I haven't found anything of the sort in LinearLayout (or any of its inherited members). Having to leave all of this initialization code in the Activity, and then having to pass it into the view seemed like it defeated the original purpose of encapsulating all of this code into a reusable view. I ended up adding two additional public methods to my view: start() and stop(). I make these calls from the activity's onResume() and onPause() methods respectively. This seems to work, but it feels like I'm using duct tape here. Does anyone know how this is typically done?
I am using the following method in a new application I'm developing. There is a main activity, which instantiates different classes that extends RelativeLayout and I'm using setContentView to switch between the different modules of the application. I wonder if this is a good approach or necessarily I have to use different activities to the several screens the app haves.
View 1 Replies View RelatedI've created a class that extends drawable that I'd like to reference inside a resource xml.
I happen to need it in a selector, like so:
CODE:.................................
What is the difference when a class extend from Handler and Thread?
As described in developer.android.com
...
Each Handler instance is associated with a single thread and that thread's message queue.
...
Does the thread has no message queue ?
Any benefit for a class extend from Handler?
I have this code...
how can I reference Home class here to replace **this**, which as it is points to OnSeekBarChangeListener.
I'm just getting into Android development, and I have a question about communicating between a receiver class and an activity class. I'm very new to JAVA and Android so I hope I don't sound too stupid. I'm developing an application where I intercept an SMS message and then based on various elements of that SMS I might delete it once it's been saved to the inbox. I have a receiver class that intercepts the txt message, and I am also able to delete messages from my inbox with code in the activity class using a button at the moment. The problem I have is communicating between the receiver class and the activity class where the code to delete a message resides. I tried putting that code directly into the receiver class but as I'm sure most of you already know the BroadcastReceiver class doesn't seem to support what I need to delete messages. I've been searching for an answer to this for a while, but haven't been able to find anything. Honestly I'm not sure I know enough about JAVA and Android to even recognize a solution if I saw it.
View 2 Replies View RelatedI'm new to Java and android development. In my application I need data which is accessible for a few activities. I've read that a good solution is to use Application class for this. So I use it like this:
public class MyApplication extends Application {
private String str;
public String getStr(){
return str;
}
public void setStr(String s){
str = s;
}
}
and I can access this variable from activity like this:........................................
I have just started android. I just want to know that how can i call activity class from other java class. i just want to pass class object to activity class.
public class GsonParser extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
MagazineThread thread=new MagazineThread();
thread.start();
}
public GsonParser(JsonMagazineParser Obj)
{
}
}
and i am just doing like from other class. GsonParser obj=new GsonParser(this);passing obj to activity class.how can i achieve that.
I made a Dialog Class with it's view classI want to pop up the dialog when I got some packets from network. so I made a Thread which parses packets and then I made if clause in Run() method There is no problem with parsing packet but when I enter "if clause" and call showDialog() I got Error message
Is there anyone who knows how to pop up a dialog from different thread?
I am trying to figure out what is the best way to go about creating dialogs. I can either create my own Dialog class (which, to me, is more clean and organized), or I can use AlertDialog.Builder (which would be done inline, and funky looking)... What are the positivies and negatives of either implementation?
View 1 Replies View RelatedI want to add tabs to the layout of my activity, but I don't want the activity to extend TabActivity. The example in http://developer.android.com/resources/tutorials/views/hello-tabwidget.html only gave example of subclass of TabActivity.
Is there any way I can make it without extending TabActivity?
instead of referring the custom widget by a fully qualified class name, is it possible to map with a shorter name. Like it happens in ant custom tasks (though properties file).
View 4 Replies View RelatedI want to build my own custom view which should look like the Crysis-GUI.At first I designed a XML-based Layout and made it visible via the setContentView(int resid)-Method. Worked pretty well.But now I wan't to go a step further and draw in my Layout. So I created a new Class, let it extend View and overrode the onDraw()-Method. So far so good.But how can I still use my XML-Layout? I can't do setContentView anymore, so how could the same effect be achieved?
View 1 Replies View RelatedWould it be there noticeable speed improvement if I would create local references to needed view elements (e.g. EditText or Button) in my activity (in onCreate()) and use them for accessing needed elements or it does not much matter if I always use findViewById() when I need to access some particular element?
View 2 Replies View RelatedSo say there's an app running (any app). I'd like to be able to get it's Activity from within a Service that will be triggered to run from a android.intent.action.SEARCH_LONG_PRESS.
Is this possible?
I have an AsyncTask that scans the file system and publishes progress through Notifications. To do this I need a reference to the current Activity in the AsyncTask.
I also don't want to kill the task when the activity is destroyed. How do I avoid leaking the activity and everything it references on each configuration change?
One possibility is to remove the reference in OnPause() to be sure it is gone when the Activity is destroyed, but that would mean notifications stops coming as soon as you leave the activity which is no good.
Isn't there a recommended way of dealing with AsyncTasks in this way?
An activity can be called from existing activity through *startActivity(intent); *
Is t possible to call an activity from non Activity class ? and how?
I am new in android
I have created 2 classes.first extends activity and 2nd extends View.
I want to add buttons,image Views etc. into the second class.
how can I do this.
CoreStartHere.java
public class CoreStartHere extends TabActivity {
t = getTabHost();
t.newTabSpec("tTask");
t.setIndicator(...);
t.setContent(new Intent().setClass(this, T1Task.class);
} t1Task.java
T1Task extends Activity {
onCreate(Bundle ...) {
:
myListview = (ListView) findViewById(R.id.hdListView);
myEditText = (EditText) findViewById(R.id.hdEditText);
hdItems = newArrayList <String>();
aa = new ArrayAdapter <String>(this, R.layout.hditemview, hdItems);
:
setOnKeyListener (new OnKeyListener() {
onKey(...) {
:
hdItems.add(0, myEditText.getText().toString());
aa.notifyDatasetChanged();
:
} } } }
hditemview.xml
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
class="com.a1.hd.hdRecordTaskListItemView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dp"
android:scrollbars="vertical"
android:textColor="@color/HD_Text"
android:fadingEdge="vertical"
/>hdRecordTaskListItemView.java
hdRecordTaskListItemView extends TextView {
// has 3 constructors
// onDraw
}
None of the constructor in hdRecordTaskListItemView get invoked and not surprisingly onDraw does not get called either. The text appears with the default style. The onDraw is supposed to draw on the "canvas".
How could i inflate my custom view using the main.xml file?
View 2 Replies View RelatedI am working on some framework. This framework code will communicate with ViewServer class, to get the various details about views. Till now we could able find few commands which viewServer class recieves and responds. But we dont have complete set of command. If any one knows, could you please provide all the supported commands by this class and what exactly it returns?
View 3 Replies View RelatedI have a class defined as
public class viewGroups extends ListActivity
Somewhere in the class I have
objItem = new clsContactGroups(context);
I am wondering what is advised to be used here? Which context?
I know four choices, but maybe there are others...
this
this.getApplicationContext()
this.getBaseContext()
this.getParent()
I use this Context to show a Toast. So I would like to show on the front-most view visible.
I have three classes one main-activity(named MainMap), one non-activity class(named MyItemizedOverlay), and one activity class(named AudioStream). I want to start AudioStream activity from non-activity class but i don't know how to.
View 1 Replies View RelatedI currently have a tab layout with 2 tabs, one tab with a list view and one with the option make strings so I can add them in the list view. Both tabs have their own activity because this made the code much more structured, and I dont have to repeat my self later.
Lets say im in the tab that offer me to create an string, and i press the update list button, how do I update the list view without startActivity()? If i use startActivity(), it starts List.java, and instead of displaying the list in the list view tab, it takes full screen, which defies the purpose of the tab view. In other words, the startActivity() steals the focus from the tab view of the list, and sends it fulscreen.
I want to update the activity in my list view tab, without starting a new activity that goes to fullscreen, and doesnt update the one in the tab.
I am using a custom class based off RelativeLayout but it obviously doesn't render in the Eclipse layout editor. I have found this article regarding LayoutInflater.Factory and it sounds like what I need to be doing but I can find no guides to using LayoutInflater.Factory.
http://www.macadamian.com/blog/post/android_-_custom_classes_from_xml_layout/
Could anyone help with exactly what and where I do this? I understand what is said in the article, but need specifics on where to declare, hook, whatever the Factory. In case it is helpful, here is the complete console output from when I try to view main.xml in Layout view..
java.lang.ClassCastException: android.view.View cannot be cast to android.view.ViewGroup
at android.view.LayoutInflater.rInflate(LayoutInflater.java:619)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:621)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:621)
at android.view.LayoutInflater.inflate(LayoutInflater.java:407)
at android.view.LayoutInflater.inflate(LayoutInflater.java:296)
at com.android.layoutlib.bridge.Bridge.computeLayout(Bridge.java:396)
at com.android.ide.eclipse.adt.internal.editors.layout.gle1.GraphicalLayoutEditor.computeLayout(Unknown Source)
at com.android.ide.eclipse.adt.internal.editors.layout.gle1.GraphicalLayoutEditor.recomputeLayout(Unknown Source)
at com.android.ide.eclipse.adt.internal.editors.layout.gle1.GraphicalLayoutEditor.activated(Unknown Source)
at com.android.ide.eclipse.adt.internal.editors.layout.LayoutEditor.pageChange(Unknown Source)
at org.eclipse.ui.part.MultiPageEditorPart.setActivePage(MultiPageEditorPart.java:1076)
at org.eclipse.ui.forms.editor.FormEditor.setActivePage(FormEditor.java:601)
at com.android.ide.eclipse.adt.internal.editors.AndroidEditor.selectDefaultPage(Unknown Source)
at com.android.ide.eclipse.adt.internal.editors.AndroidEditor.addPages(Unknown Source)
at org.eclipse.ui.forms.editor.FormEditor.createPages(FormEditor.java:138)
at org.eclipse.ui.part.MultiPageEditorPart.createPartControl(MultiPageEditorPart.java:357)
at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:662)
at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:462)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595)
at org.eclipse.ui.internal.PartPane.setVisible(PartPane.java:313)
at org.eclipse.ui.internal.presentations.PresentablePart.setVisible(PresentablePart.java:180)
at org.eclipse.ui.internal.presentations.util.PresentablePartFolder.select(PresentablePartFolder.java:270)
at org.eclipse.ui.internal.presentations.util.LeftToRightTabOrder.select(LeftToRightTabOrder.java:65)
at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation.selectPart(TabbedStackPresentation.java:473)
at org.eclipse.ui.internal.PartStack.refreshPresentationSelection(PartStack.java:1256)
at org.eclipse.ui.internal.PartStack.setSelection(PartStack.java:1209)
at org.eclipse.ui.internal.PartStack.presentationSelectionChanged(PartStack.java:843)
at org.eclipse.ui.internal.PartStack.access$1(PartStack.java:829)
at org.eclipse.ui.internal.PartStack$1.selectPart(PartStack.java:139)
at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation$1.handleEvent(TabbedStackPresentation.java:133)
at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.fireEvent(AbstractTabFolder.java:270)
at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.fireEvent(AbstractTabFolder.java:279)
at org.eclipse.ui.internal.presentations.defaultpresentation.DefaultTabFolder.access$1(DefaultTabFolder.java:1)
at org.eclipse.ui.internal.presentations.defaultpresentation.DefaultTabFolder$2.handleEvent(DefaultTabFolder.java:87)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1176)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1200)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1185)
at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:1025)
at org.eclipse.swt.custom.CTabFolder.setSelection(CTabFolder.java:3256)
at org.eclipse.swt.custom.CTabFolder.onMouse(CTabFolder.java:2045)
at org.eclipse.swt.custom.CTabFolder$1.handleEvent(CTabFolder.java:323)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1176)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3493)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3112)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2405)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2369)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2221)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:500)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:493)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:194)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:368)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:559)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:514)
at org.eclipse.equinox.launcher.Main.run(Main.java:1311)