Develop Reference

switch case using variables, repetitive code

I have 50 Buttons. I use the switch statement as shown below. Each case has the same On-Click code. But I make many changes to the code for each Button, and it's really tedious work and very repetitive to change the code the same way 50 times. My code currently looks like this:
public void ButtonOnClick(View v) {
switch (v.getId()) {
case button1:
if(button_list.get(1).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(1).getText().toString());
is_clicked= (String)button_list.get(1).getTag();
if ("0".equals(is_clicked)){
button_list.get(1).setBackgroundResource(R.drawable.button_pressed);
button_list.get(1).setTag("1");
}else{
button_list.get(1).setBackgroundResource(R.drawable.button_normal);
button_list.get(1).setTag("0");
}
break;
case button2:
if(button_list.get(2).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(2).getText().toString());
is_clicked= (String)button_list.get(2).getTag();
if ("0".equals(is_clicked)){
button_list.get(2).setBackgroundResource(R.drawable.button_pressed);
button_list.get(2).setTag("1");
}else{
button_list.get(2).setBackgroundResource(R.drawable.button_normal);
button_list.get(2).setTag("0");
}
break;
case button3:
if(button_list.get(3).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(3).getText().toString());
is_clicked= (String)button_list.get(3).getTag();
if ("0".equals(is_clicked)){
button_list.get(3).setBackgroundResource(R.drawable.button_pressed);
button_list.get(3).setTag("1");
}else{
button_list.get(3).setBackgroundResource(R.drawable.button_normal);
button_list.get(3).setTag("0");
}
break;
case button4:
if(button_list.get(4).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(4).getText().toString());
is_clicked= (String)button_list.get(4).getTag();
if ("0".equals(is_clicked)){
button_list.get(4).setBackgroundResource(R.drawable.button_pressed);
button_list.get(4).setTag("1");
}else{
button_list.get(4).setBackgroundResource(R.drawable.button_normal);
button_list.get(4).setTag("0");
}
break;
case button5:
if(button_list.get(5).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(5).getText().toString());
is_clicked= (String)button_list.get(5).getTag();
if ("0".equals(is_clicked)){
button_list.get(5).setBackgroundResource(R.drawable.button_pressed);
button_list.get(5).setTag("1");
}else{
button_list.get(5).setBackgroundResource(R.drawable.button_normal);
button_list.get(5).setTag("0");
}
break;
case button6:
if(button_list.get(6).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(6).getText().toString());
is_clicked= (String)button_list.get(6).getTag();
if ("0".equals(is_clicked)){
button_list.get(6).setBackgroundResource(R.drawable.button_pressed);
button_list.get(6).setTag("1");
}else{
button_list.get(6).setBackgroundResource(R.drawable.button_normal);
button_list.get(6).setTag("0");
}
break;
case button7:
if(button_list.get(7).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(7).getText().toString());
is_clicked= (String)button_list.get(7).getTag();
if ("0".equals(is_clicked)){
button_list.get(7).setBackgroundResource(R.drawable.button_pressed);
button_list.get(7).setTag("1");
}else{
button_list.get(7).setBackgroundResource(R.drawable.button_normal);
button_list.get(7).setTag("0");
}
break;
case button8:
if(button_list.get(8).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(8).getText().toString());
is_clicked= (String)button_list.get(8).getTag();
if ("0".equals(is_clicked)){
button_list.get(8).setBackgroundResource(R.drawable.button_pressed);
button_list.get(8).setTag("1");
}else{
button_list.get(8).setBackgroundResource(R.drawable.button_normal);
button_list.get(8).setTag("0");
}
break;
case button9:
if(button_list.get(9).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(9).getText().toString());
is_clicked= (String)button_list.get(9).getTag();
if ("0".equals(is_clicked)){
button_list.get(9).setBackgroundResource(R.drawable.button_pressed);
button_list.get(9).setTag("1");
}else{
button_list.get(9).setBackgroundResource(R.drawable.button_normal);
button_list.get(9).setTag("0");
}
break;
case button10:
if(button_list.get(10).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(10).getText().toString());
is_clicked= (String)button_list.get(10).getTag();
if ("0".equals(is_clicked)){
button_list.get(10).setBackgroundResource(R.drawable.button_pressed);
button_list.get(10).setTag("1");
}else{
button_list.get(10).setBackgroundResource(R.drawable.button_normal);
button_list.get(10).setTag("0");
}
break;
Is there a way I can use a general variable to access each case so if I make a change I won't need to make it 50 times for each button? I thought about doing something like this:
public void ButtonOnClick(View v) {
switch (v.getId()) {
case button[i]
if(button_list.get(i).getTag().equals("0"))
enter_txt.setText(enter_txt.getText()+button_list.get(i).getText().toString());
is_clicked= (String)button_list.get(i).getTag();
if ("0".equals(is_clicked)){
button_list.get(i).setBackgroundResource(R.drawable.button_pressed);
button_list.get(i).setTag("1");
}else{
button_list.get(i).setBackgroundResource(R.drawable.button_normal);
button_list.get(i).setTag("0");
}
break;
Would this work? Or is there something else I need to do so I don't need to make 50 changes to my code every time I decide I want to change the OnClick method?

I'm going to assume that ButtonOnClick is the click handler for the buttons. I'm going to further assume that for any i, the contents of button_list.get(i) is the button. If that's right, then the argument v is the same Button object stored in the list. You can then reduce your entire handler to:
public void ButtonOnClick(View v) {
Button btn = (Button) v;
if (btn.getTag().equals("0")) {
enter_txt.setText(enter_txt.getText()+btn.getText().toString());
}
is_clicked= (String) btn.getTag();
if ("0".equals(is_clicked)){
btn.setBackgroundResource(R.drawable.button_pressed);
btn.setTag("1");
}else{
btn.setBackgroundResource(R.drawable.button_normal);
btn.setTag("0");
}
}
As an aside, you might consider using Boolean objects instead of String objects as the button tags.

First you should never copy paste code, try to extract your code in another method.
If you are using a arraylist where you store all your buttons, you can probably use the ArrayList.indexOf(Object o)
So just replace your ButtonOnClick method with this one, you can handle other buttons behavior easily too in the future :
public void ButtonOnClick(View v) {
if(button_list.contains(v))
{
setButtonBackground(button_list.indexOf(v));
}
}
private setButtonBackground(int buttonNumber)
{
Button myButton = (Button) button_list.get(buttonNumber);
if(myButton.getTag().equals("0"))
{
enter_txt.setText(enter_txt.getText()+myButton.getText().toString());
}
is_clicked = (String) myButton.getTag();
if ("0".equals(is_clicked))
{
myButton.setBackgroundResource(R.drawable.button_pressed);
myButton.setTag("1");
}
else
{
myButton.setBackgroundResource(R.drawable.button_normal);
myButton.setTag("0");
}
}
When you are developping instead of copy and paste code, just use the shortcut extract to a method so you will get something like this and will save yourself time.
[...]
case button1:
setButtonBackground(1);
break;
case button2:
setButtonBackground(2);
break;
[...]
Let me know if it works for you

Adding touch pointers in an android app

I'd like to add more than two pointers.
Here is the current code that works:
if (id == 0)
textView1.setText(touchStatus);
else
textView2.setText(touchStatus);
How would I add a third, forth, fifth...?

switch(id) {
case 0:
textView1.setText(touchStatus);
break;
case 1:
textView2.setText(touchStatus);
break;
case 2:
textView3.setText(touchStatus);
break;
case 3:
textView4.setText(touchStatus);
break;
...
}

onClick event buttons

I have 5 buttons,each of them open another activity. How to make clickeble only one of them at current moment?When i click 2 different buttons simultaneusly onClick event calls 2 times and 2 different activities opens. How can i resolve my problem. Thanks.My code
public void onClick(View v)
{
switch (v.getId())
{
case R.id.play_button:
onPlayClick();
setButtonsEnable(false);
break;
case R.id.difficalty_button:
onDifficultyClick();
setButtonsEnable(false);
break;
case R.id.hight_scores_button:
onHighScoresClick();
setButtonsEnable(false);
break;
case R.id.share_button:
setButtonsEnable(false);
break;
case R.id.turn_off_button:
onLeaderboardClick();
setButtonsEnable(false);
break;
default:
break;
}
}
After return to main activity i make my buttons clickable
protected void onResume() {
super.onResume();
setButtonsEnable(true);
}
public void setButtonsEnable(boolean config)
{
playBtn.setClickable(config);
difficultyBtn.setClickable(config);
hScoreBtn.setClickable(config);
shareBtn.setClickable(config);
turnOffButton.setClickable(config);
}

setOnClickListener(null)
would do the trick or you can make
setClickable(false)

Maybe what you really need is RadioGroup? It allows out of the box to select click/select only one button at the time.
Doc reference
Tutorial

Create a variable clicked in Activity:
boolean clicked=false;
Set this value in onClick code:
public void onClick(View v)
{
if(!clicked){
clicked=true;
switch (v.getId())
{
case R.id.play_button:
onPlayClick();
setButtonsEnable(false);
break;
case R.id.difficalty_button:
onDifficultyClick();
setButtonsEnable(false);
break;
case R.id.hight_scores_button:
onHighScoresClick();
setButtonsEnable(false);
break;
case R.id.share_button:
setButtonsEnable(false);
break;
case R.id.turn_off_button:
onLeaderboardClick();
setButtonsEnable(false);
break;
default:
break;
}}
}

If you want to open an activity on each click, use a onclicklistener for each button or add a method call in the xml layout via android:onClick="someMethod", when you click a button and call another activity the UI should block itself...have you tried it this way?

Switch Statement with Button pressed

So I push either button1, button2, button3, or button4. Pushing any of these Buttons calls method buttonPressed(View v). I want to use a different case depending on the button pressed. For example:
public void buttonPressed(View v){
switch(v){
case button1:
//do something
case button2:
//do something
case button3:
//do something
case button4:
//do something
}}
Obviously, this does not work. I cannot use a switch statement with a View. What is the easiest and most efficient solution to this problem? Thanks!!
Note: I am using android:onClick="buttonPressed" in my .xml

You need to switch on the View's ID, not the View itself
public void buttonPressed(View v){
switch(v.getId()) {
case R.id.ButtonOneID:
//do something
break;
case R.id.ButtonTwoID:
//do something
break;
case R.id.ButtonThreeID:
//do something
break;
case R.id.ButtonFourID:
//do something
break;
}
}

public void buttonPressed(View v){
int id = v.getId();
switch(id){
case button1.getId();
//do something
break;
case button2.getId();
//do something
break;
case button3.getId();
//do something
break;
case button4.getId();
//do something
break;
}
}

How to move to next case in switch condition

I am in need of a code, using which in my Android App, I want to go through all the cases of switch condition , (Not randomly!!!).I am able to move it randomly as follows.
public void switchingLogic(){
Random rand = new random();
int i = rand.nextInt(4)+1;
switch (i) {
case 1:
setImages(R.drawable.ic_launcher, R.drawable.ic_launcher);
selectedCorrectImage(img1, R.raw.correct_img, R.raw.thats_correct);
selectedWrongImage(img2, R.raw.wrong_img, R.raw.no_its_wrong);
break;
case 2:
setImages(R.drawable.ic_launcher, R.drawable.ic_launcher);
selectedCorrectImage(img1, R.raw.correct_img, R.raw.thats_correct);
selectedWrongImage(img2, R.raw.wrong_img, R.raw.no_its_wrong);
break;
case 3:
setImages(R.drawable.ic_launcher, R.drawable.ic_launcher);
selectedCorrectImage(img1, R.raw.correct_img, R.raw.thats_correct);
selectedWrongImage(img2, R.raw.wrong_img, R.raw.no_its_wrong);
break;
case 4:
setImages(R.drawable.ic_launcher, R.drawable.ic_launcher);
selectedCorrectImage(img1, R.raw.correct_img, R.raw.thats_correct);
selectedWrongImage(img2, R.raw.wrong_img, R.raw.no_its_wrong);
break;
}
But now I want to just go in order from 1 through 4...
If the condition(Selected image) is correct in first case, I am showing Image in fullscreen and calling back the method again.
I just came across CURSOR .
Can I use it(if yes , How?) or is there any way I can solve this.
Important: I Want to use this "Switching Logic method" in onCreate()

If you dont set the break command in a switch-case, switch wont terminate after executing one case and move to the next one. so this code:
int i = 2;
switch(i) {
case 1:
// do something
case 2:
// do something
case 3:
// do something
}
will execute case 2 and case 3. Maybe you can implement an ifclause to define if the cases should break or not.

You can try creating 2 methods to do this:
a method to loop through all cases by using a for loop
a method that contains your cases
Then just call
LoopThroughAllCases();
The code would look something like this.
void LoopThroughAllCases()
{
int minCaseValue = 0; // modify to suit your case
int maxCaseValue = 4; // modify to suit your case
for (int i = minCaseValue ; i <= maxCaseValue ; i++)
{
Cases(i);
}
}
void Cases(int i)
{
switch (i)
{
case 0:
// do something
break;
case 1:
// do something
break;
case 2:
// do something
break;
case 3:
// do something
break;
case 4:
// do something
break;
default:
//handle unknown value
break;
}
}