ImageButton first click / second click? - android

I have an ImageButton with the image resource R.drawable.img1 and I want to change the image from R.drawable.img1 to R.drawable.img2 or from R.drawable.img2 to R.drawable.img1 everytime I click on the ImageButton.
I was trying this way but it doesn't work:
Integer img1 = (Integer) gridlayout.getChildAt(index).getTag(R.drawable.img1);
Integer img2 = (Integer) gridlayout.getChildAt(index).getTag(R.drawable.img2);
if(img1 == R.drawable.img1){
//code...
}else if(img2 == R.drawable.img2){
//code...
}
I set ImageButton's dynamically with this code:
ImageButton imgBtn1 = new ImageButton(this);
imgBtn1.setId(id);
imgBtn1.setImageResource(R.drawable.img1);
imgBtn1.setTag(R.drawable.ing1);
imgBtn1.setScaleType(ImageView.ScaleType.CENTER_CROP);
imgBtn1.setPadding(5,5,5,5);
GridLayout.LayoutParams params = new GridLayout.LayoutParams();
params.setMargins(-7,-7,-7,-7);
params.width = fieldSize;
params.height = fieldSize;
gridlayout.addView(imgBtn1, index, params);
Thanks!

I am just giving one of the several solutions available ,what i would is in the onCreate i would load the imagebutton with one of images available ,then i would create a class variable i and would set it to 1, when ever i click the imagebutton ,on the onClick of it ,i would increment i and do this
if(i%2==0)
{
setImage1;}
else
{set image2;}

So, if you want to display a different button each time, I would create two buttons in the layout, hide one and show one. When the visible one is clicked, hide it and show the second button. I think that will be easier. You can alternatively use a local class variable to keep count of clicks and switch buttons accordingly.

public boolean showingFirst = true;
if (showingFirst) {
//code here for set needed image on first click
showingFirst = false;
} else {
//code here for set needed image on Second click
showingFirst = true;
}

Related

Android Development - Create a menu with 3 imageButtons

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.

Android: Dynamically create image button with click event

I'm new to android and I require to have a list of image buttons in an activity which are created based on the data in a database. I haven't created anything like this in android before and so far I've been using HTML tables to show my data in a grid view. I'm not asking for any special code, I'm just clueless on how to implement this. I wanna know what the best approach is.
One problem I've faced is with the click events(in the way I've been doing them so far) which do not take in any EventArg, so I can't get the name of the button out of them.
If you're sure that the OnClickListener instance is applied to a Button, then you could just cast the received view to a Button and get the text:
public void onClick(View v) {
// 1) Possibly check for instance of first
Button b = (Button)v;
String buttonText = b.getText().toString();
}
// create the layout params that will be used to define how your button will be displayed
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
// Create Button
final Button btn = new Button(this);
// Give button an ID
btn.setId(someinteger);
btn.setText("Add Text");
// set the layoutParams on the button
btn.setLayoutParams(params);

Some alternative to hundreds of buttons

Im going to write some android app, which will basically consists of two activities. So first should have a lot of buttons (100+) and on click on any of them I will just get some special id and move to second activity. But is there any alternative to declare that hundreds of buttons and copy/paste one piece of code to every of them setting almost same onClickLister? Is there any special construction? Thanks
Edit: every of buttons are actually indexed from 1 to n. And on the click second activity will be launched and get that index to show it. I cant basically use any spinner or smth else, because there will be 3 rows of clickable things and each of them carring different images
Edit 2: so, to give you an idea, im going to do some table of buttons like in Angry Birds menu when you actually choosing the level you want to play. So, on click you will get id of button and start second activity
Call the method to add buttons
private void addButton(){
LinearLayout view = (LinearLayout) findViewById(R.id.linear_layout_id_here);
Button btn = null;
int w = 50;
int h = 25;
for(int i=1; i<100; i++) {
btn = new Button(this);
btn.setLayoutParams(new LayoutParams(w,h));
btn.setText("button " +i);
btn.setTag(""+i);
btn.setOnClickListener(onClickBtn);
view.addView(btn);
btn = null;
}
}
Call this method for handling onclick on button
private View.OnClickListener onClickBtn = new View.OnClickListener() {
public void onClick(View view) {
final int tag = Integer.parseInt(view.getTag().toString());
switch (tag) {
case 1:
// Do stuff
break;
case 2:
// Do stuff
break;
default:
break;
}
}
};
You should use a ListView.
ListViews are great for handling a lot of items at the same time. They are also natural for the user. Additionally, you use only one click listener - OnItemClickListener.
There's a useful example on how to work with ListViews in the Android Referenence.
You may add buttons in code, something like this:
#Override
public void onCreate(Bundle savedInstanceState) {
/*your code here*/
GroupView gw =findViewById(R.id.pnlButtonscontainer); //find the panel to add the buttons
for(int i=0; i<100; i++) {
Button b = new Button(this);
b.setLayoutParameters(new LayoutParameters(w,h));
b.settext = i+"";
b.setOnClickListener(new OnClickListener(){
});
}
}
I coded directly into browser, so some syntax error may appear in my code, but this is the point, a way, not the only one, to add 100 buttons.

Android : get the id of dynamically generated ImageButton when clicked

I have dynamically generated ImageButtons with different ImageResource for each ImageButton. Now I want to know which ImageButton was clicked, how can I determine this ?
Need your help.
Thanks.
you can set an id for each created ImageButton and getId() for check witch button clicked
ImageButton im=new ImageButton(Yourcontext);
im.setId(giveAnID);
//where you check
int theID=im.getId();
In order to do this you could do two things:
Firstly, when dynamically generated the ImageButton you could call setId() in order to set a specific id to this View and store it in List, etc.
Then when you have a click event (or anything else), you can call the getId() method of the View to get the id.
Then you can compare and do anything you want.
Hope this helps!
Any resource is uniquely identified by its id which is generated in R.java file.
So you can use something like :
if(image.getId() == R.id.image) {
// do awesome stuff
}
If your code generates the imageButtons then, in this code you can write something like,
imageButton.setId(1);
and when your imageButton is clicked then you can get it with,
int id = imageButton.getId();
i had to do same thing and this is what i have done
for(int i = 0 ;i<mediaList.size();i++){
view_media_gallery_item = LayoutInflater.from(view.getContext()).inflate(R.layout.e_media_gallery_item, null);
TextView title = (TextView) view_media_gallery_item.findViewById(R.id.media_gallery_item_title);
TextView subtitle = (TextView) view_media_gallery_item.findViewById(R.id.media_gallery_item_subtitle);
ImageView flux_Title_Image =(ImageView) view_media_gallery_item.findViewById(R.id.media_gallery_item_img);
title.setId(i+100);
subtitle.setId(i+1000);
flux_Title_Image.setId(2000+i);
title.setText("" +mediaList.get(i).getTitle());
subtitle.setText(""+mediaList.get(i).getArtist());
System.out.println("view added::::");
view_media_gallery_item.setTag(mediaList.get(i));
view_media_gallery_item.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
System.out.println("view media clicked");
Media m = (Media )v.getTag();
medialistner.setOnItemclick(m);
}
});

Android: Knowing which button is pressed for buttons that are created programatically

I am trying to do this:
Programatically create 4 buttons on a layout. Then, create an onclick listener for each of the button. Then, based on which button is pressed, will do some logic.
I have created a LinearLayout in my XML file and called it "layout".
So, my codes go something like this:
layout = (LinearLayout)findViewById(R.id.layout);
//Create the array of buttons
Button [] subjectButtons_BT = new Button[4];
for(int i=0; i<4; i++){
subjectButtons_BT[i] = new Button(this);
// Add the button to the layout
layout.addView(subjectButtons_BT[i]);
subjectButtons_BT[i].setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
// if it is the first button, do LOGIC1
// if it is the second button, do LOGIC2 etc
}
});
}
So far, I have managed to create the 4 buttons and I can click on the buttons.
However, I do not know how to the logic in the setOnClickListener part.
I wanted to know which button is pressed. So, I tried using v.getId() but it always returns a -1.
Can someone advise if this is the right way to go? And if so, how to do the logic?
Thanks.
You have two options for identify which dynamic button is clicked.
1) Set ID to the button and compare ID
2) Set Tag to the button if you have come more information about button
and want to access it
1) You can set id to the button and in onClick() method you can get id by button.getId() method and you can compare ids and perform action according to click.
2) If you set tag then you have to get tag by calling button.getTag() method and by this way you can pass object with the button
You can set the id of the buttons after you create them, and then check for that id within the OnClickListener
layout = (LinearLayout)findViewById(R.id.layout);
//Create the array of buttons
Button [] subjectButtons_BT = new Button[4];
for(int i=0; i<4; i++){
subjectButtons_BT[i] = new Button(this);
subjectButtons_BT[i].setId(i);
// Add the button to the layout
layout.addView(subjectButtons_BT[i]);
subjectButtons_BT[i].setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
int id = v.getId();
if (id == 0) {
} else if (id == 1) {
}
//etc.
}
});
}

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