I have a button to which I attach an onClickListener via code. I have to to this through code because it's in a fragment.
The listener works fine when in landscape mode, but when it's in portrait it doesn't. There's no "click" sound even.
In my xml file, I set the initial visibility of the button to invisible and then make it visible later when the user clicks a radio button in the same Viewgroup as the button. The onclicklisteners of the radiobuttons are working just fine in both portrait and landscape mode.
Now if I remove the "android:visibility="invisible" code in xml, the onclickstener works fine in portrait mode! But of course I need it invisible till the user clicks a radiobutton otherwise the UI doesn't make sense. Very weird indeed.
Here's my code:
private void setOnClickForSaveButton(View v) {
Button changeFundsSave = (Button) v.findViewById(R.id.change_funds_save);
changeFundsSave.setOnClickListener(saveListener);
}
Button.OnClickListener saveListener = new Button.OnClickListener() {
#Override
public void onClick(View v) {
//Get the rootview
View rootView = v.getRootView();
EditText changeFundsEdit = (EditText) rootView.findViewById(R.id.change_funds_edit);
if(changeFundsEdit.getText().toString().equals("")) {
new AlertDialog.Builder(getActivity())
.setTitle( "" )
.setMessage( "Enter the number of units" )
.setPositiveButton( "Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
}
})
.show();
return;
}
}
};
private void setOnClicksForRadioButtons(View v) {
RadioButton rb1 = (RadioButton)v.findViewById(R.id.add_units);
RadioButton rb2 = (RadioButton)v.findViewById(R.id.remove_units);
RadioButton rb3 = (RadioButton)v.findViewById(R.id.set_units);
rb1.setOnClickListener(addRemoveSetButtonListener);
rb2.setOnClickListener(addRemoveSetButtonListener);
rb3.setOnClickListener(addRemoveSetButtonListener);
}
OnClickListener addRemoveSetButtonListener = new OnClickListener() {
#Override
public void onClick(View v) {
// Since we only have the radiobutton view, we need to get the parent
View rootView = v.getRootView();
//Make the controls visible
TextView changeFundsText = (TextView) rootView.findViewById(R.id.change_funds_text);
EditText changeFundsEdit = (EditText) rootView.findViewById(R.id.change_funds_edit);
Button changeFundsSave = (Button) rootView.findViewById(R.id.change_funds_save);
changeFundsText.setVisibility(View.VISIBLE);
changeFundsEdit.setVisibility(View.VISIBLE);
changeFundsSave.setVisibility(View.VISIBLE);
}
};
}
Solved the problem! In portrait mode, like everyone else I load one fragment in a separate activity. Out of habit I was calling setContentView(something) before loading the fragment! So ultimately the two layouts were overlapping each other and the visible and invisible buttons were overlapping each other and things must have gotten messed up. Damn, I'm not sure if I like the concept of fragments at all. My first time using them. But maybe I just need to learn how to wire them up properly before I get used to them :) Thank you so much for your help
my guess is that
1) do you findViewById again for the view you passed in setOnClickForSaveButton? since the old view will be destroyed and a view will be created when you change screen orientation
2) do you have multiple ids for R.id.change_funds_save
3) add a log at the first line of onclick(v) to see if it is called but goto another branch you didnt expect.
Unless you are loading two separate xml layout files from layout-land and layout-port, there shouldn't be much difference between landscape mode and portrait mode. That being said, I'm going to take a wild guess and say that your app is probably not working correctly due to configuration changes. Let me know if this is actually true... i.e. does your app work at first, but stops working when you rotate the screen?
If this is true, you should look into how the Activity lifecycle is affecting your views and onClickListeners.
Related
I've been searching for a solution for this for a while but cannot seem to get one working. There are one or two on here about this subject but I can't seem to get them going. I'm also a novice in Android and while I've been on and off playing with it for a few years, I still understand next to nothing about what I'm writing.
Basically I've got a TextView and a button. Ideally I'd like to put some text in the TextView, press a button it's gone, press the button again and it's back.
I've narrowed it down to needing to understand what findViewById(R.id.button2) does but honestly I'm a bit lost.
I've added my button code but apologies that this is such a noob question
public void onClick(Button v){
TextView t1 = (TextView)findViewById(R.id.editText);
v.setVisibility(View.GONE);
Button button = (Button) findViewById(R.id.button2);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
TextView t1 = (TextView)findViewById(R.id.TextView);
v.setVisibility(View.GONE);
}
});
}
Your code has a couple of issues. I'm not going to give you the code because that won't really help you learn. Instead I'll explain things and let you try to figure it out or come back with more explicit questions.
You know that xml file you set using setContentView? Some of the tags in it had a property android:id="xxxx". That xxxx is the id of that view, its used so you can find that view in your code. The findViewById function walks through all the views on screen and finds a view with that id and returns it. That gives you a reference to the view so you can change it. For example, you can set its visibility, set its background color, or set an OnClickListener.
So to have a button toggle the visibility of another view, you need to be able to do the following things:
1)Find the view who's visibility you want to change
2)Figure out what its visibility currently is
3)Figure out what you want it to be (the opposite of what it currently is
4)Set that visibility
You need to write a function that does all that. Then you need to do this
1)Find the button you want to use to change the visibility
2)Tell it to call your function when its pressed.
Figure out how to do each of those steps individually, and you should be able to put it together. Good luck.
findViewById(R.id.button2) finds the view with the id button2.
You can check inside onClick whether t1 is visible or not (t1.setVisibility(View.GONE); not v.setVisibility(View.GONE);), and toggle between View.GONE and View.VISIBLE.
Remember that your findViewById() should have a real id. They are normally set on the activity_name.xml.
You are using a onClick inside a onClick. Personally I recommend setting the listener manually with setOnClickListener.
There's a lot of work for you, start with these tutorials. Keep trying and try to understand what you are doing.
Look like you need a toogle button feature, here is a piece of code.
Important: you must pay heed to #GabeSechan and #SkyDriver2500 answers.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.your_layout);
//your other code
Button button = (Button) findViewById(R.id.button2);
final TextView t1 = (TextView) findViewById(R.id.editText);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
t1.setVisibility(t1.getVisibility() == View.VISIBLE ? View.GONE : View.VISIBLE);
}
});
}
I'm not sure if the code will help you now. But just in case, here it is
final boolean[] isTvVisible = {false};
final TextView t1 = (TextView)findViewById(R.id.editText);
t1.setVisibility(View.GONE);
Button button = (Button) findViewById(R.id.button2);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
if (isTvVisible[0]) {
t1.setVisibility(View.GONE);
isTvVisible[0] = false;
} else {
t1.setVisibility(View.VISIBLE);
isTvVisible[0] = true;
}
}
});
First of all english is not my first language but i will try my best.
Also... i am pretty sure my title choice was not the best so sorry for that.
Basically what i wanted to do is a menu with three ImageButtons but there is a tricky part (tricky for me at least) since every time i press one button that same button changes image (to a colored version instead of a grayed out image) and the other two change as well from colored version of their respective images to grayed out ones, actually only one of the other two will change since the purpose of this is to be able to activate only one at a time so it would not be possible to have the other two active at the same time.
Notice that this is not a menu on the top right corner but just a set of three ImageButtons on a activity or Fragment.
I already tried a lot of stuff to make that happen but so far no luck but i think i know why though i can't find a workaround for this since i am actually new in android dev.
what i tried was inside the setOnClickListener of any of those buttons such as:
eventsButton.setOnClickListener(
new View.OnClickListener() {
public void onClick(View view) {
ImageButton eventsButton = (ImageButton) view.findViewById(R.id.eventsButton);
eventsButton.setBackgroundResource(R.drawable.events_icon_active);
eventsButton.setClickable(false);
}
}
);
i tried to add the functions to change the other imageButtons as well like:
eventsButton.setOnClickListener(
new View.OnClickListener() {
public void onClick(View view) {
ImageButton eventsButton = (ImageButton) view.findViewById(R.id.eventsButton);
eventsButton.setBackgroundResource(R.drawable.events_icon_inactive);
eventsButton.setClickable(false);
ImageButton contactsButton = (ImageButton) view.findViewById(R.id.contactsButton);
contactsButton.setBackgroundResource(R.drawable.contacts_icon_inactive);
contactsButton.setClickable(true);
ImageButton interestsButton = (ImageButton) view.findViewById(R.id.interestsButton);
interestsButton.setBackgroundResource(R.drawable.interests_icon_inactive);
interestsButton.setClickable(true);
}
}
);
and i repeated that three time, always setting the other buttons clickable and setting their images to the inactive one (the grayed out one), also setting the button i click as no longer clickable.
But from what i gather i cant do any references to any other buttons inside the eventsButton.setOnClickListener like the buttons interestsButton or contactsButton, it will crash the app as soon as i touch any of those three buttons with the following error message:
Attempt to invoke virtual method 'void android.widget.ImageButton.setBackgroundResource(int)' on a null object reference
And it always point to the first line where i make a reference to another button other then the one used to start the setOnClickListener.
If you can just point me in the right direction i would be tremendously grateful.
All the best
You can declare your ImageViews as final outside the scope of the listener and when the onClickListener(View v) is called you can then just call setBackground because they are final and you can reference them from inside the listener.
Something like this:
final ImageView view1 = (ImageView) findViewById(R.id.view1id);
final ImageView view2 = (ImageView) findViewById(R.id.view2id);
view1.setOnClickListener(
new View.OnClickListener() {
public void onClick(View view) {
// do whatever you want to the ImageViews
// view1.setBackground...
}
}
);
eventsButton.setOnClickListener(
new View.OnClickListener() {
public void onClick(View view) {
ImageButton contactsButton = (ImageButton) view.findViewById(R.id.contactsButton);
contactsButton.setBackgroundResource(R.drawable.contacts_icon_inactive);
contactsButton.setClickable(true);
}
}
);
Your problem is in view.findViewById(R.id.contactsButton): view here is the button being clicked (the events one), and by calling view.findViewById(contactsButton) you are implicitly saying that the contact button is a child of view, which is not.
Just use findViewById() (from Activity), getActivity().findViewById() (from Fragments), or better container.findViewById() (if you have a reference to the layout containing the three buttons).
I'm not saying that yours is the most efficient way to deal with a menu, just pointing out your error.
You can first make things simple; I suggest:
you add 3 array (Arraylist might be better) fields in your activity class, one for the buttons, one for the active resources and one for the inactive resources
initialize those arrays in the onCreate method;
define a single onClickListener object and use it for all the buttons; Use a loop in the onClick method, see bellow.
In terms of code, it looks like this:
ImageButton[] buttons;
int[] activeResources;
int[] inactiveResources;
protected void onCreate2(Bundle savedInstanceState) {
View.OnClickListener onClickListener = new View.OnClickListener(){
public void onClick(View view) {
ImageButton clickedButton = (ImageButton) view;
for(int i = 0; i<buttons.length; i++){
ImageButton bt = buttons[i];
if(clickedButton==bt){
bt.setBackgroundResource(inactiveResources[i]);
bt.setClickable(false);
}else{
bt.setBackgroundResource(activeResources[i]);
bt.setClickable(true);
}
}
}
};
buttons = new ImageButton[3];
activeResources = new int[3];
inactiveResources = new int[3];
int idx = 0;
buttons[idx] = (ImageButton) findViewById(R.id.eventsButton);
inactiveResources[idx] = R.drawable.events_icon_inactive;
activeResources[idx] = R.drawable.events_icon_active;
idx = 1;
buttons[idx] = (ImageButton) findViewById(R.id.contactsButton);
inactiveResources[idx] = R.drawable.contacts_icon_inactive;
activeResources[idx] = R.drawable.contacts_icon_active;
idx = 3;
buttons[idx] = (ImageButton) findViewById(R.id.interestsButton);
inactiveResources[idx] = R.drawable.interests_icon_inactive;
activeResources[idx] = R.drawable.interests_icon_active;
for(int i =0; i<buttons.length; i++){
buttons[i].setBackgroundResource(activeResources[i]);
buttons[i].setOnClickListener(onClickListener);
}
}
Do not expect it to run right the way, I am giving only ideas, you have to look and see if it fit for you are looking for.
I'm Making simple app for project
That App contains lot of text so i want,
"when a button is pressed, text should Change in same layout"
like PowerPoint slide.
I want change text only not scroll.
Now i made my app, have lots of Windows or Layouts.
It is not looking good, too much layout in simple app so please help me .
Thanks in advance
Doing this is very easy, I will quickly walk you through the Algorithm:
Set a class level variable called as FLAG initialize it to 1.
Let us assume that FLAG = 1 will represent the first slide. FLAG = 2 the second slide and so on.
Now in your button click you can use a switch case or an if else condition, based on the value of the flag display the relevant text in textview.
Once done, increment the flag, for the next set of sentence(s).
Class level:
int FLAG = 1;
onCreate:
Initialize your textView:
TextView mtv = (TextView)findViewById(R.id.yourid);
Set a button click listener:
private View.OnClickListener slides = new View.OnClickListener() {
#Override
public void onClick(View v) {
if(FLAG ==1)
mtv.setText("First slide");
else if(FLAG ==2)
mtv.setText("Second Slide");
//and so on...
FLAG = FLAG+1;//increment flag
}
};
Hi i have two textViews that i initially set its visibility to gone then animate in and become visible. now i want to make the invisible again but for some reason they're still showing on screen does anyone no why?
in my onCreate() i make the view gone
register = (TextView)findViewById(R.id.register);
register.setVisibility(View.GONE);
forgotpassword = (TextView)findViewById(R.id.forgotpw);
forgotpassword.setVisibility(View.GONE);
then later on i make it visible
public void run()
{
animations();
loginForm.setVisibility(View.VISIBLE);
register.setVisibility(View.VISIBLE);
forgotpassword.setVisibility(View.VISIBLE);
}
and then when a user presses a button i want the text views to become invisible so that they retain their layout but they stay visible on screen
signInBtn = (Button) findViewById(R.id.signin);
signInBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
signInProcess();
}
});
public void signInProcess() {
register.setVisibility(View.INVISIBLE);
forgotpassword.setVisibility(View.INVISIBLE);
setuploader.setVisibility(View.VISIBLE);
}
In Android when you animate something, It's just drawn somewhere else. The actual element is not moved. So when you animate signInBtn it's drawn somewhere else, but the actual button is not moved from the original position. So when you click the button the click handler is not called.
To avoid this set fillAfter = True in your animation so the button will actually get moved at the end of your animation.
Also, after animating a view in Android make sure you call View.clearAnimation() before trying to change its visibility.
I have a button and when I press it, i want to remove it (not make it invisible). I read that I can do that using layout.removeView(mybutton) but what is the layout ? and how can I get it in my activity
Button showQuestion;
private void initialize() {
showQuestion = (Button) findViewById(R.id.bAnswerQuestionShowQuestion);
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.bAnswerQuestionShowQuestion:
showQuestion.setVisibility(View.INVISIBLE);
//Here i want to delete the button
question.setVisibility(View.VISIBLE);
theAnswer.setVisibility(View.VISIBLE);
answerQuestion.setVisibility(View.VISIBLE);
showChoices.setVisibility(View.VISIBLE);
showHint.setVisibility(View.VISIBLE);
break;
}
}
see link
ViewGroup layout = (ViewGroup) button.getParent();
if(null!=layout) //for safety only as you are doing onClick
layout.removeView(button);
i have a button and when i press it , i want to remove it (not make it
invisible)
=> You did as below:
showQuestion.setVisibility(View.INVISIBLE);
Try with:
showQuestion.setVisibility(View.GONE);
FYI, INVISIBLE just hide the view but physically present there and GONE hide as well remove the presence physically as well.
You can use
button.setVisibility(View.GONE);
Layout is the parent Layout of your Button, usually a RelativeLayout or LinearLayout.
You can get it as follows:
ViewParent layout = button.getParent();