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Android - In a button On click event, button goes missing

I am trying to change the text color of button on click event. But while the button click event is fired, button goes missing. Code mentioned below.
Button design in Layout XML file
<Button
android:id="#+id/btnCategory1"
android:background="#000000"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:textColor="#FFFFFF"
android:layout_margin="10dp"
>
</Button>
Activity.java file
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_expense);
btnType1 = (Button)findViewById(R.id.btnCategory1);
btnType1.setOnClickListener(this);
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(v == (View)btnType1)
{
btnType1.setTextColor(R.color.darkorange);
}
}
Tried the below Option also. Still Button Goes missing. Log statement is fired successfully.
btnType1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.v("AAAAAAAAAAA","BBBBBBBBBBB");
// TODO Auto-generated method stub
btnType1.setTextColor(R.color.orange);
}
});
If someone can find the reason, kindly share it.

You cannot use just the R.color integer when calling setTextColor. You need to call getResources().getColor(R.color.YOURCOLOR) to set a color properly.
Make your button as below
Button bOne = (Button) findViewById(R.id.btnCategory1);
bOne.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
bOne.setTextColor(getResources().getColor(R.color.YOURCOLOR));
}
});

Hmmmmm. I'm not seeing a good reason as to why that would happen.
I do think that there is maybe a better/cleaner way to do something so simple, and so I'll tell you it - go ahead and try it. This was should work.
Get rid of the btnType1.setOnClickListener(this); line from your java.
Then, go into your xml and add this to your button:
android:onClick="methodName"
Now, if you go into your java and create a method called methodName that takes a view as an argument:
public void methodName(View v) {
btnType1.setTextColor(R.color.darkorgange);
}
The color should be updated!
EDIT: Just looked again and the reason the previous code wasn't working was because you were trying to update btnType2, not btnType1. Still, try the method I just gave you. It is good practie, and a cleaner and easier way to do things for the future.
EDIT2:
All right, the mystery is solved. Here is your issue. When you do set color, you need to pass in the actual color, not just the id. Here is what you need to change that line to:
btnType1.setTextColor(getResources().getColor(R.color.darkorange));

Change View Text Color by code

Well, I developed a menu with eight Buttons for an App. So, every time the user clicks on in one of the buttons, such button changes its background. And I would would like to change its color as well. But I got now idea how, since setTextColor does not work with Views.
I'm using View because its part of onClick method that I override in order to achieve what I want. So, here go the code:
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
v.setBackgroundResource(R.drawable.degrade_menu);
}
So, how could I change the text color?
Cheers,

Cast your v to TextView and then set the text color. Do not forget to read color from resourse
((TextView)v).setTextColor(getResources().getColor(R.color.errorColor));

quick solution:
final Button button = (Button) findViewById(<id>);
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
button.setTextColor(<color>);
}
};
better solution: use states

Cast the view to a button. Then you can use settextcolor

EditText's selectAll() does not select the text, instead cursor is moved to position 0

My situation is: I have a EditText, and under it I have a button, called "select all". It's purpose is to let the user select all the text by pressing it.
When the button is clicked, I invoke selectAll() on the EditText, but instead of selecting all text, in some cases (generally, when the cursor is already positioned within the text somewhere), the cursor is moved to position 0 (start of text) and text remains unselected. Second click on the button will then select all. But of course it should happen on first click.
From this issue: Android EditText selectAll() doesn't works if one taps on the same field in android 4.x only it seems that this is a bug in android 4.0 and above. (Found no mention in Google issue tracker).
Does anyone know about a way to overcome this problem? It seems that the probelm is also in other selection methods and not only selectAll().
(p.s. This question is sort of duplicate of the issue I mentioned above. But I opened another question, because the author of that issue was satisfied and selected a partial answer (of setting android:selectAllOnFocus="true"), while in my case and scenario it does not help me and does not solve the problem.
Thanks.

Problem caused by IME. If showed cursor drag pointer then selection must be zero width.
You need cancel drag pointer. It can be doned by change text. For example replace:
Editable text = edit.getText();
if (text.length() > 0) {
text.replace(0, 1, text.subSequence(0, 1), 0, 1);
edit.selectAll();
}
We replace first symbol of text with same symbol. It cause cancel drag pointer and allow make selection without bug.

I was having a similar issue. I solved it (using Xamarin in C#, but the equivalent Java will work) with the following code:
private void InitFocus()
{
Java.Lang.Runnable rable = new Java.Lang.Runnable(()=>
{
EditText maleCount = FindViewById<EditText>(Resource.Id.txtMaleCount);
maleCount.RequestFocus();
maleCount.SelectAll();
});
new Handler().Post(rable);
}
I have 2 controls: One is a dropdown that lets you select a chicken house and then a set of buttons for each day of the week. Whenever you change the day of week or the chicken house, I want to set focus in the txtMaleCount EditText and then I want the value in that box selected (since it's a number and they're presumably going to replace it).
Clearly, the non-intuitive part was the need to Post it. Doing it directly (on the UI thread) didn't seem to have any effect.

Try this:
yourEditText.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//((EditText)v).selectAll();
((EditText)v).setSelection(startValue, stopValue);
}
});
Or This:
yourEditText.setOnFocusChangedListener(new OnFocusChangedListener(){
#Override
public void onFocusChange(View v, boolean hasFocus){
if (hasFocus){
//((EditText)v).selectAll();
((EditText)v).setSelection(startValue, stopValue);
}
}
});
Or this:
theEditText.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
EditText editText = (EditText)view;
editText.setSelection(editText.getText().length()-1); // selects all the text
}
});
Or this:
theEditText.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
EditText editText = (EditText)view;
editText.performLongClick();
}
});
Hope this helps .. :)

Android calculator buttons

I am trying to make a calculator for Android. Here is the code for my buttons:
int[] button_ids = {
R.id.BtnNum0, R.id.BtnNum1, R.id.BtnNum2, R.id.BtnNum3, R.id.BtnNum4, R.id.BtnNum5, R.id.BtnNum6,
R.id.BtnNum7, R.id.BtnNum8, R.id.BtnNum9, R.id.BtnAdd, R.id.BtnSub, R.id.BtnDiv, R.id.BtnMult,
R.id.BtnClear, R.id.equals
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
EditTextValue = (EditText) findViewById(R.id.editText1);
TVValue = (TextView) findViewById(R.id.textView1);
buttons = new ArrayList<Button>();
for(int id : button_ids) {
Button button = (Button)findViewById(id);
button.setOnClickListener(this);
buttons.add(button);
}
}
How I can change this part to a block of code where I won't have to declare the IDs of the buttons? (e.g. R.id.BtnNum0)
int[] button_ids = {
R.id.BtnNum0, R.id.BtnNum1, R.id.BtnNum2, R.id.BtnNum3, R.id.BtnNum4, R.id.BtnNum5, R.id.BtnNum6,
R.id.BtnNum7, R.id.BtnNum8, R.id.BtnNum9, R.id.BtnAdd, R.id.BtnSub, R.id.BtnDiv, R.id.BtnMult,
R.id.BtnClear, R.id.equals
};
I have been searching for an answer, but I still can't find a solution.

What you can do, since this code seems to only set a single OnClickListener for all Buttons, is to do it in xml
For each Button set
android:onClick="functionName"
then in your code you can do away with all of the id's and your for loop. In Java just create a function like
public void functionName(View v)
{
switch (v.getId())
{
case R.id.buttonId:
// do work for this Button
break;
...
}
The way you are doing it is fine but this is how I prefer to handle this situation. You just have to give all of the Buttons the same function name in xml then use that name as your function name in Java. You also just have to be sure to declare the function with a void return type and make sure it takes a View as its one and only parameter as in my example.
The Button Docs also have an example of this

in your layout file add this to every button
<Button
...
android:onClick="btnClicked"
.../>
then in your code add this method and check for each button in this method
public void btnClicked(View v)
{
switch(v.getId())
{
case R.id.BtnNum0:
// your code
break;
....
}
}

That is likely the best solution unfortunately, unless you use some sort of annotation framework which still doesn't cut down much on the boilerplate.
edit:
You could try to get a pointer to whatever ViewGroup is holding the Button views and then getting all of its children, and then looping through them while casting them to Buttons as you go.
For example: If your Button objects in XML are housed in a LinearLayout, you could get the pointer to that and do something like this:
for(int i=0; i < ((ViewGroup)v).getChildCount(); ++i) {
Button nextChild = (Button) ((ViewGroup)v).getChildAt(i);
}
Of course, I recommend against this, but it is still a possibility.

As trevor-e suggested, you can give an annotation processor a try. Android Annotations can simplify your code to:
#Click
public void BtnNum0() {
// Button 0 clicked
}
#Click
public void BtnNum1() {
// Button 1 clicked
}
// etc.
If you go this route, please do try to use names following the Java convention as the button names correspond with function names.

cant see textview items is clicked or not

I have created the textview dynamically. My whole project is in white background so I made this textview background white. If I click one of the textview items it should take me to another activity. I got that output.
But my problem is I cant see Textview is clicked or not. I have done this through textview.setClickable(true). I can see if it is black background. can anyone help me please
Sorry I forgot to add, My textcolor is black

you have to implement onClickListener for that text field, for example:
yourTextField.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
}
});