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Common Header with click events of Header from all Activities in Xamarin android

I am developing a xamarin android application, where I used to call a Header activity in all Activities. My code is as Fallows
My Main.axml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/container"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!-- Header aligned to top -->
<include layout="#layout/Header"
android:id="#+id/includeheader"
android:layout_alignParentTop="true" />
<!-- Content below header and above footer -->
<include layout="#layout/Content"
android:id="#+id/includecontent" />
<!-- Footer aligned to bottom -->
<include layout="#layout/Footer"
android:id="#+id/includefooter"
android:layout_alignParentBottom="true"/>
</RelativeLayout>
My Header.axml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:id="#+id/header"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TableLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:minHeight="50dip">
<TableRow
android:background="#2c2c2c"
android:padding="10dip">
<TextView
android:id="#+id/scanHome"
android:layout_width="0dip"
android:layout_weight="2.5"
android:textSize="22sp"
android:textStyle="bold"
android:gravity="center"
android:text="" />
<Button
android:id="#+id/Settings"
android:layout_width="0dip"
android:layout_height="30dip"
android:layout_marginLeft="10dip"
android:layout_weight="0.17"
android:gravity="center"
android:width="35dip"
android:clickable="true"
android:onClick="SettingsClick"/>
<Button
android:id="#+id/logout"
android:layout_width="0dip"
android:layout_height="40dip"
android:layout_weight="0.27"
android:gravity="center"
android:width="40dip" />
</TableRow>
</TableLayout>
</LinearLayout>
MainActivity.class
namespace LayoutApp
{
[Activity(Label = "LayoutApp", MainLauncher = true, Icon = "#drawable/icon")]
public class MainActivity : Header
{
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.Main);
setHeading("Scan Home");
}
}
}
Header.class
[Activity(Label = "LayoutApp", MainLauncher = false)]
public abstract class Header : Activity , View.IOnClickListener
{
private TextView HeaderText;
private Button Settings;
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.Header);
Settings = FindViewById<Button>(Resource.Id.Settings);
Settings.Click += delegate
{
};
}
protected void setHeading(string text)
{
if (HeaderText == null)
HeaderText = FindViewById<TextView>(Resource.Id.scanHome);
if (HeaderText != null)
HeaderText.Text = text;
}
public void SettingsClick()
{
}
}
Hence I am using Header Activity in MainActivity like in native android using include Property. When I load Main Launcher, Header is also displaying but click events are not working from the MainActivity where as text is applying from setHeading method.
When debugging , error is populating as 'java.lang.illegalistateexception: could not find a method SettingsClick(View) in the activityclass for onclick handler on view class'.
So, my issue here is I would like to get click events of Header.

The layout files (AXML) are not linked to Activities with the same names as theirs.
In your Main.axml code, you are including (adding) the layout code from Header.axml; however, your MainActivity.cs code has no relations with the Main.axml, just like the HeaderActivity.cs code has no relations with the Header.axml code.
In the MainActivity.cs code, the SetContentView(Resource.Layout.Main) applies the Main.axml layout (which contains the Header.axml code) to your MainActivity, but does not apply the methods from HeaderActivity.cs.
If you want an app with Toolbar and Bottom Bar in your app, there is a good tutorial here: http://mateoj.com/2015/06/21/adding-toolbar-and-navigation-drawer-all-activities-android/
You should also take a look on Android Fragments.

#kumar Sudheer, I don't know the xamarin development, but I can understand what you want to do by looking at the code and exception you get.
Just pass the View object as parameter in the SettingClick method of your header activity
public void SettingsClick(View v)
{
}
In android when you define the click handler in layout file then the signature of that method would be public void <clickHandler>(View v) {}.
You've not passed the View parameter in the method that's why system is unable to find your method in Activity and that's why you are getting the java.lang.IllegaliStateException

Button - Textview click event issue - Android studio

I have a list of buttons in my activity_main, Once i clicked on Button_A it is taking me to the next list of buttons layout for eg. Button_A1.
And once i clicked Button_A1 it should show me the text which i have written in text_view. But here its getting failed. Once i Clicked in Button_A1, it showing like "your app is stopped". Can you guys help me on this, as i am new on this platform.
**Button_A1.xml:**
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="Small Text"
android:id="#+id/textView2"
android:layout_gravity="center_vertical"
android:onClick="Button_A1" />
</LinearLayout>
**button_A1.java:**
public class Ov1 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.ov1);
}
}
Do i have to give activity entry in manifest.xml. Please help me on this..
Button_A ----> Button_A1 ----> Textview

Clicked in Button_A1, it showing like "your app is stopped"
Because Button_A1 method is not available in Ov1 class. add method as:
public void Button_A1(View view) {
////
}
NOTE: To make TextView click-able need to add android:clickable="true" attribute in TextView xml

Android toggle button display wrong value after orientation change

Here is my problem.
I've got a simple activity which set a layout, and add rows in a table-layout(itself in a scroll view).
Those table-rows have a custom layout with a text-field and a toggle button.
Each toggle button has a value taken from a database, and when I first create the activity, the values are OK. But when I turn the device and then change the orientation, all the toggles-button take "false" value. I printed the values that I set in the Logcat, and the values are the good ones (those in the database).
I thought something like the layout I want is hidden behind another layout, but I made some tests and the text-fields change with new values, so I really don't understand why the toggle buttons don't work.
Here is the code :
TableRow layout :
<?xml version="1.0" encoding="utf-8"?>
<TableRow xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<RelativeLayout
android:id="#+id/relativelayout_row_parametres"
android:layout_width="fill_parent"
android:layout_height="50dp"
android:layout_weight="1.0">
<TextView
android:id="#+id/textview_row_parametres"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textColor="#android:color/black"
android:textStyle="bold"
android:textSize="20sp"
android:layout_marginLeft="2dp"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
/>
<ToggleButton
android:id="#+id/togglebutton_row_parametres"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:layout_marginRight="2dp"
android:textOn="#string/togglebutton_on"
android:textOff="#string/togglebutton_off" />
</RelativeLayout>
</TableRow>
Activity Layout :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<ImageView style="#style/header" />
<LinearLayout
android:layout_width="fill_parent" android:layout_height="0dp"
android:layout_weight="0.8"
android:background="#drawable/gradient_bg"
android:padding="10dip"
android:orientation="vertical">
<ScrollView
android:layout_width="fill_parent" android:layout_height="0dp"
android:layout_weight="0.85"
android:fillViewport="true"
android:padding="10dip"
android:layout_gravity="center">
<TableLayout
android:id="#+id/tablelayout_parametres"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#drawable/cornered_bg"
android:paddingTop="5dip"
android:paddingBottom="5dip">
</TableLayout>
</ScrollView>
<Button
android:id="#+id/button_parametres_accept"
android:gravity="center"
android:text="#string/accept_changes"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="0.15"
android:layout_gravity="center_horizontal" />
</LinearLayout>
</LinearLayout>
And the activity code:
public class Parameters extends Activity {
#Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
}
#Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
final Map<String, Boolean> changes = new HashMap<String, Boolean>();
final Context ctx = getApplicationContext();
LanguageManager.updateConfig(this);
setContentView(R.layout.parametres);
CountryDB[] countries = Database.instance(getApplicationContext()).getCountries();
TableLayout tabLayout = (TableLayout) findViewById(R.id.tablelayout_parametres);
for(int i =0; i<countries.length; i++){
TableRow newRow = (TableRow) getLayoutInflater().inflate(R.layout.row_parametres, null);
TextView textView = (TextView) newRow.findViewById(R.id.textview_row_parametres);
ToggleButton toggleButton = (ToggleButton) newRow.findViewById(R.id.togglebutton_row_parametres);
toggleButton.setChecked(countries[i].isToSynchronize());
toggleButton.setTag(countries[i]);
Log.e("setChecked",""+toggleButton.getId()+"/"+countries[i].isToSynchronize());
textView.setText(countries[i].getLabel());
toggleButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
CountryDB countryTemp = (CountryDB) v.getTag();
changes.put(countryTemp.getLabel(), ((ToggleButton)v).isChecked());
}
});
tabLayout.addView(newRow);
TableRow rowDivider = (TableRow) getLayoutInflater().inflate(R.layout.row_divider, null);
tabLayout.addView(rowDivider);
}
Button buttonValidation = (Button) findViewById(R.id.button_parameters_accept);
buttonValidation.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Iterator<String> iterator = changes.keySet().iterator();
while(iterator.hasNext()){
String stringTemp = iterator.next();
Database.instance(ctx).updateCountry(stringTemp, changes.get(stringTemp));
}
Intent intent = new Intent(ctx, Splash.class);
String result = "restart";
String from = "parameters";
Intent returnIntent = new Intent();
returnIntent.putExtra("result", result);
returnIntent.putExtra("from", from);
setResult(RESULT_OK, returnIntent);
startActivity(intent);
}
});
}
}
In the Log.e, I print the values, and they are good, the display on togglebuttons is wrong, they are just all "false".
Thanks for your help.

Between onCreate() and onResume() , Android tries to restore the old state of the toggle Buttons. Since they don't have unique ID's , Android wont succeed and everything is false again. Try to move your setChecked() calls into onResume() ( maybe onStart() works too).
Here is a pretty good answer to the same Question:
ToggleButton change state on orientation changed

you have to save data before Orientation.
Android have method onSaveImstamceState(Bundle outState) and onRestoreInstanceState(BundleInstaceState)
override these method in Activity.

There's a simpler solution: you only need to add configChanges property to your activity declaration, like stated here. This way you can prevent Activity restart when orientation changes. So in your manifest you should have something like
<activity android:name=".Parameters"
android:configChanges="orientation|keyboardHidden">
or if your buildTarget>=13
<activity android:name=".Parameters"
android:configChanges="orientation|keyboardHidden|screenSize">
Edit: Like reported on comments below, this is not an optimal solution. The main drawback is reported in a note of the document linked above:
Note: Handling the configuration change yourself can make it much more difficult to use alternative resources, because the system does not automatically apply them for you. This technique should be considered a last resort when you must avoid restarts due to a configuration change and is not recommended for most applications.

Communication between custom SurfaceView and default android's views

My problem is communication between custom GameView (extends SurfaceView) and TextView: I want to set TextView's text from inside of the GameView.
In main activity i'm using this layout file, it should explain structure of my app:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#00ff00"
>
<TextView
android:id="#+id/scoreTV"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="score: 0"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="back"
android:layout_alignParentRight="true" />
</RelativeLayout>
<org.gk.grApp.GameView
android:id="#+id/gameplayScreen"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
</LinearLayout>
I can't change TextView's text in my GameView object, because it's impossible to touch UI thread from another.
Handler doesn't work too, because i can't give a handler's reference to GameView's constructor, that is performed after loading this xml file (a read about default constructor for xml files eg here How can I use GLSurfaceView in a LinearLayout together with other Views, such as TextView or Button?).
Do you have any idea what I should do now? Maybe my deduction is wrong, so please, tell me about this.
EDIT: I changed my xml file, instead of GameView I have now:
<LinearLayout
android:id="#+id/gameplayScreen"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
</LinearLayout>
Also I added an argument (third) into constructor's signature:
public GameView(Context context, AttributeSet as, Handler h) { ... }
and changed my onCreate in GameplayActivity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gameplay);
LinearLayout ll = (LinearLayout)findViewById(R.id.gameplayScreen);
GV = new GameView(this, null, scoreHandler);
ll.addView(GV);
}
It works, now I can set TextView's text but after clicking on the back button another exception is thrown:
"Performing pause of activity that is not resumed: {org.gk.grApp/org.gk.grApp.MainMenuActivity}". I just started searching information about this.

First make a reference to the TextView on the activity level:
TextView txv;
In onCreate assign this reference:
txv = (TextView) findViewById(R.id.MyTextView);
Then make a method in your Activity after onCreate like this:
public void setTextView(final String txt){
MyActivity.this.runOnUiThread(new Runnable() {
public void run() {
txv.setText(txt);
}
});
}
Then you make a call from your custom view:
((MyActivity) getContext()).setTextView(str);

Drawing into scrollView

my problem I know is simple, but for the life of me I cant get an answer...
I have a LinearLayout that got a scrollview inside it... in the scroll view (in code) it should call a custom ScrollView to show on the application... it only shows black, nothing in it... here is my code
first the xml... simple LL with a textview, scrollview and button
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView android:layout_height="wrap_content"
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:text="test field" android:layout_alignParentTop="true"/>
<ScrollView android:layout_width="600dp"
android:layout_height="300dp"
android:id="#+id/v1"
android:fillViewport="true"/>
<Button android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/gfx"
android:text="Gfx"
></Button>
</LinearLayout>
Now the onCreate of that activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
cw = getWindowManager().getDefaultDisplay().getWidth();
ch = getWindowManager().getDefaultDisplay().getHeight();
v = Draw2d findViewById(R.id.v1);
context = this;
setContentView(R.layout.gfx);
mDbHelper = new DbAdapter(this);
mDbHelper.open();
}
Draw2d is the class of the custom scrollView declared like so (it does have onDraw and everything. If I set the contentview to the Draw2d object directly it'll show no problem, but I need it withen a LL)
public static class Draw2d extends ScrollView{
public Draw2d(Context context) {
super(context);
}
Please any help is appreciated

Maybe because of you have nothing in the ScrollView? Try putting something in it. Check this link, you see there is another linear layout in the scrollview with "30px" layout height making the scrollview appear. If the layout_height was wrap_content, you would not see the scrollview if there is enough place on the screen for it.