I have created a function
public void setTabHome(int index) { }
on main.java page. This function is to set the page by index.
By default, index is 0. I want to call main.java page from main1.java with the parameter index set to 1.
You can set the method to static and then call it again.
I would just insert that method again in main1.java though ¯_(ツ)_/¯
or even better access main1.java through an Intent.
public static void setTabHome(int index) { }
main.setTabHome(indexnumber)
Make an instance of your main.java class in main1.java class. Using this instance, you can call the function in main.java. Like this
Main main = new Main();
main.yourfunctionName();
But better you make another function in main1.java and use this function. Beacuse the parameters you used in one activity may cannot be used in another activity.
main.java define a public static instance in the class
public class Menu extends Activity{
public static Menu instance = null;
#Override
public void onCreate(Bundle savedInstanceState) {
instance = this;
}
public void setTabHome(int index) { }
}
main1.java call like this:
Menu.instance.setTabHome(number);
Related
I have an Activity in whose onCreate() method i call a Utility function.
This utility functions requires a callback class instance as a parameter, in which it returns the info that i need. this is:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Utility.functionA(new functionACallBack() {
/**
*
*/
private static final long serialVersionUID = -7896922737679366614L;
#Override
public void onResponse(String error) {
((MyActivity) AppClass.getAppContext()).finish();
}
});
}
Once I have obtained that info, I want to close the activity. so i called finish() from inside the anonymous class that i created for the callback.
But the activity is not getting finished. I thought maybe i need to call finish() from UI thread so i did runOnUiThread(), in inside it also i tried calling finish(). But it just doesn't work.
Could someone please help me with this issue?
UPDATE:
I am storing APP context and then trying to use that but to no avail.
public class AppClass extends Application {
private static Context mContext;
#Override
public void onCreate() {
super.onCreate();
AppClass.mContext = getApplicationContext();
}
public static Context getAppContext(){
return AppClass.mContext;
}
}
Simply call something like this:
#Override
public void onResponse(String error) {
((Activity) context).finish();
}
As this is a static function, you'll have to be able to access your Context in a static way. You can save that as a Class variable, but you'll have to be aware about its handling as it might lead to memory leaks.
To avoid them, you can declare a class that extends Application and save here your context, so this way you won't ever have a memory leak.
Try using this code:
((Activity) ActivityClass.this).finish();
Remember, use the Activity class, not the Application one.
I stuck at this issue many times and I passed the problem in different ways and I'm not sure that I made it in the right way.
I simplified the problem in a the following example. I know that I can pass only the data to the class but I do want to pass the editText cause I have this problem with more difficult UI controls.
mainactivity.java
public class mainactivity extends Activity {
public EditText clickEditText;
int count =0;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
newTxt();
}
public void newTxt() {
txt = new MyText(context);
txt.updateTextEdit("Main Activity");
}
}
myText.java
public class MyText
{
private Context _context;
// constructor
public MyText(Context context)
{
_context = context;
}
public void updateTextEdit(String str)
{
private EditText strEditText;
strEditText= (EditText)findViewById(_context.R.id.editTextClick); // ????
strEditText.setText(str + " and myTxt");
}
}
if you could explain me how to fix the updateTextEdit function. i passed the context of the main activity. How can I change the editText? Thank you very much!!!
If you really want to do this this way, you need to save a reference to Activity, not Context. Like this:
public class MyText
{
private Activity _activity;
// constructor
public MyText(Activity activity)
{
_activity= activity;
}
public void updateTextEdit(String str)
{
private EditText strEditText;
strEditText= (EditText)activity.findViewById(R.id.editTextClick);
strEditText.setText(str + " and myTxt");
}
}
and in newTxt() you will need to change:
txt = new MyText(context);
to:
txt = new MyText(this);
But wouldn't it be easier to just put this method inside your activity? Why do you want it in another class? If it really needs to be in another class, you could make that class an inner class of your activity and you would still have access to the activity's methods and member variables.
There's a similar question here
How to access Activity UI from my class?
You didn't say how you obtained the context, you should use this and get the mainactivity in the other class. not context.
then you can call runOnUIThread to perform UI updates.
I have a public void in one class and I want to call it in another class when it creates but nothing seems to be working. here is the code of my first activity
public class activityone extends Activity {
public void actionC() {
//actions
}
Does anyone know how to call it in my second class?
In general, you need to have an instance of your activityone class in order to call an instance method.
To create an instance, you generally use a constructor like:
activityone a = new activityone();
a.actionC();
I'm not sure this is what you want though, because Activitys are generally created by the Android system itself and you should handle the onCreate method instead.
Here is what you can do:
public class activityone extends Activity {
/*public void actionC() {*/ //Instead on normal method, write your actions in onCreate()
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//actions
}
and in your second activity, do this:
Intent intent = new Intent(getApplicationContext(),activityone.class);
startActivity(intent);
Hope it helps !!!
I have a title bar in my application. And the title bar has one button. On click of that button I display info activity. Now, as far as I know, android:onClick needs a reference of a public method inside the activity which has the xml set in setContentView(). Now, as the logic for that buttons click will be the same throughout the application, so what I want is, I will the method just once say showInfoScreen(View view) and put it in that buttons onClick attribute. And I need not write the same method everywhere. Is it possible?
Of course it's possible. Write an Activity class, then have all of your Activitys extend it. For example:
public abstract class BaseActivity extends Activity {
#Override
public void setContentView( int layoutResID ) {
super.setContentView( layoutResID );
findViewById(R.id.button).setOnClickListener(new OnTitleBarButtonClickListener());
}
private void showInfoScreen() {
// Show the info screen
}
private class OnTitleBarButtonClickListener implements OnClickListener {
#Override
public void onClick(View v) {
showInfoScreen();
}
}
}
Then all of your derived Activitys would extend BaseActivity instead of Activity.
The beauty of doing it this way is that any Activity that extends this class automatically gets this feature. No coding is required in the derived classes, just in BaseActivity. The only contract all of your Activitys will have will be to have R.id.button or whatever id you name it within its content.
I think you have to write onclick in every Activity where you want to display infoscreen.
But OnClick you just call A method showInfoScreen(View view) in every Activity....
And you should create class Like...ShowInfo and there are one static method...
public class ShowInfo{
public static void showInfoScreen(View view,Context c){
//now dispay info here
}
}
Write ShowInfo.showInfoScreen(v,YourClassName.this) in your onClick() Method....
An example of what Vinayak.B suggested is like this:
public class yourAppUtils {
public static void yourMethod() {
// Do stuff
}
}
i have a tabActivity that hold 3 tabs.
from one tab i want to open another tab and run a method that refresh the data.
i use this method to switch tabs
public void switchTabInActivity(int indexTabToSwitchTo) {
MyTabsActivity ParentActivity;
ParentActivity = (MyTabsActivity) this.getParent();
ParentActivity.switchTab(indexTabToSwitchTo);
}
to open the tab but i cant' call the method.
any ideas?
According to me, I believe what you are doing here is correct, but still you are not doing the entire flow. Let me explain,
Calling the above method will redirect you to that particular tab. But what you actually have to do is to execute some method in that class. But were are you calling that method.
Consider a Activity with onCreate(),
you could have called that method in your onCreate(). But now when you execute your
public void switchTabInActivity(int indexTabToSwitchTo) {
MyTabsActivity ParentActivity;
ParentActivity = (MyTabsActivity) this.getParent();
ParentActivity.switchTab(indexTabToSwitchTo);
}
method, this will call the onResume() of that activity. So my suggestion would be to override the onResume method of your particular activity which has that method..
you can simply create a static method which can be easily call by using ClassName.methodName();
see example,
public class myAnotherClass
{
public static void accessFromAnotherClass()
{
System.out.println ( "I am accessed publically" );
}
}
// Now Accessing above class method from another class file
public class myFirstClass
{
private void myClassMethod()
{
myAnotherClass.accessFromAnotherClass(); // called from another class. in your case , another tab.
}
}