I'm new to android development..
I have this code in my main class:
Button prevBtn, pauseBtn, nextBtn;
EditText counterTxt;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_affirmations);
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
prevBtn = (Button)findViewById(R.id.prevBtn);
pauseBtn = (Button)findViewById(R.id.pauseBtn);
nextBtn = (Button)findViewById(R.id.nextBtn);
counterTxt = (EditText)findViewById(R.id.counterTxt);
prevBtn.setOnClickListener(new View.OnClickListener() {
int t = Integer.parseInt(counterTxt.getText().toString());
public void onClick(View v) {
counterTxt.setText(String.valueOf(t-1));
}
});
nextBtn.setOnClickListener(new View.OnClickListener() {
int t = Integer.parseInt(counterTxt.getText().toString());
public void onClick(View v) {
counterTxt.setText(String.valueOf(t+1));
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_affirmations, menu);
return true;
}
When I click "Previous", the text field value becomes 19.
When I click "Next", the text field value becomes 21.
But it only displays these two values, nothing else, no matter if i click again. I want to subtract or add 1 whenever i click the appropriate buttons.
I think this happens because the event Listeners are inside onCreate() method? Any idea on how to make it update each time I click?
You need to move your parseInt inside your onClick:
nextBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
int t = Integer.parseInt(counterTxt.getText().toString());
counterTxt.setText(String.valueOf(t+1));
}
});
In both cases, t is defined as a member variable of the listener, and never changed. move it inside the onClick method instead, like this (in both cases):
public void onClick(View v) {
int t = Integer.parseInt(counterTxt.getText().toString());
counterTxt.setText(String.valueOf(t-1));
}
Related
I'm a beginner in Android Studio, and I want to make a C button in calc with 2 functions.
How do I do that on one tap the C button erases only one number, and on hold erase all numbers in TextView?
findViewById(R.id.btnClear).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
txtScreen.setText(""); // Clear the screen
// Reset all the states and flags
lastNumeric = false;
stateError = false;
lastDot = false;
You can set an onClickListener and onLongClickListener to achieve this.
cButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
String currentText = textView.getText().toString();
if(currentText.length >= 2){
currentText = currentText.substring(0, currentText.length - 2);
}else{
currentText = "";
}
textView.setText(currentText);
}
});
cButton.setOnLongClickListener(new View.OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
textView.setText("");
return true;
}
});
Have you looked in to the onClick() and onLongPress() methods?
cancelButton.setOnLongClickListener(new OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
myTextView.setText("");
return true;
}
});
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
removeOneCharacter();
}
});
private void removeOneCharacter()
{
String textViewValue = myTextView.getText().toString();
if (textViewValue != null && textViewValue.length >= 2)
{
myTextView.setText(textViewValue.substring(0, textViewValue.length() - 2);
}
}
The onClick() method removes on char from the TextView at a time. The onClick() method however removes the entire String from the TextView but only considering if there is already 2 or more characters to prevent an Exception from occurring due to the upper-bound of the substring.
An improvement here could be to add another if function that checks the character length within the Long press and performs a clear if there is only one character remaining.
I am using this library this library.I used the code described in its description on github. looks like this I have event for the menu buttons, not its main Button. i want to get its main button's click event for make rest layout blur when its clicked/expended. even want to hide or set its default state when user click or touch somewhere else on screen.
FloatingActionButton actionC = new FloatingActionButton(getBaseContext());
actionC.setIcon(R.drawable.notes);
actionC.setTitle("Add note");
actionC.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//
}
});
FloatingActionsMenu floatingActionsMenu = (FloatingActionsMenu)findViewById(R.id.multiple_actions);
floatingActionsMenu.addButton(actionC);
// ((FloatingActionsMenu) findViewById(R.id.multiple_actions)).addButton(actionC);
final FloatingActionButton actionA = (FloatingActionButton) findViewById(R.id.action_a);
actionA.setIcon(R.drawable.event);
actionA.setTitle("Make life Event");
actionA.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//
}
});
and the answer is .
floatingActionsMenu.setOnFloatingActionsMenuUpdateListener(new FloatingActionsMenu.OnFloatingActionsMenuUpdateListener() {
#Override
public void onMenuExpanded() {
Toast.makeText(Launcher.this, "Fdf", Toast.LENGTH_LONG).show();
}
#Override
public void onMenuCollapsed() {
}
});
This is the first time I'm ever dabbling in Android development so please bear with me.
My requirement is this:
I have two buttons on screen, A and B. If the user presses both buttons (order doesn't matter), I need another page to be displayed. Pressing either A or B should do nothing.
Is this possible? If so, how would I achieve this?
Thank you.
This is possible if you take a flag. (boolean)
You should set a flag in your button listeners.
public class Mtest extends Activity {
Button b1;
Button b2;
boolean flag_1 = false;
boolean flag_2 = false;
public void onCreate(Bundle savedInstanceState) {
...
b1 = (Button) findViewById(R.id.b1);
b2 = (Button) findViewById(R.id.b2);
b1.setOnClickListener(myhandler1);
b2.setOnClickListener(myhandler2);
}
View.OnClickListener myhandler1 = new View.OnClickListener() {
public void onClick(View v) {
// it was the 1st button
flag_1 = true;
doSomething();
}
};
View.OnClickListener myhandler2 = new View.OnClickListener() {
public void onClick(View v) {
// it was the 2nd button
flag_2 = true;
doSomething();
}
};
}
public void doSomething(){
if(flag_1 && flag_2)
{
//DO SOMETHING
}
}
}
Create two boolean's like button1isClickedand button2isClicked,then set an onClickListener for each Button. When the the Button is clicked set the value of these two boolean's to true, then simply create an if() statement that will chekc to see if both buttons have been clicked, like this:
if(button1isClicked == true && button2isClicked == true){
//display your new page
}
I have actually read several answers to this but they are so different than the simple way I am implementing click responses that I am wondering if there is a way to add something simple to what I am doing to create an onLongClick responas.
Basically, all my XML code is written with statements like this:
android:onClick="onSync"
Then my Java has:
public void onSync(View v) {
...
Toast toast3=Toast.makeText(this, "Sync was pressed",Toast.LENGTH_SHORT);
toast3.show();
}
What I would like to do is have a different function that is called when the button gets a long press. Right now, a long press causes the same action as a short press.
Specifically, I would like to know how to interface to a routine such as this:
public void onSyncLong(View v) {
...
Toast toast3=Toast.makeText(this, "Long Sync was pressed",Toast.LENGTH_SHORT);
toast3.show();
}
I would certainly appreciate any help on this problem. It would be great if the reply told me what to do in the XML and in the Jave. Thanks so much.
----------------------------UPDATE------------------------
Here is my onCreate code:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.start_meters);
textLL = (TextView)findViewById(R.id.textLL);
textTimer = (TextView)findViewById(R.id.textTimer);
textTimeToLine = (TextView)findViewById(R.id.textTimeToLine);
Button button = (Button) findViewById(R.id.button_sync);
button.setOnLongClickListener(new OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
// TODO Auto-generated method stub
return true;
}
});
}
And here is the button XML segment
<Button
android:id="#+id/buttonSync"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="Gun/Sync"
android:onClick="onSync"
android:textSize="#dimen/font_small"
android:background="#drawable/round_button"
android:padding="3sp"
android:longClickable="true"/>
------------Final Update----------------
Here is the working code:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.start_meters);
textLL = (TextView)findViewById(R.id.textLL);
textTimer = (TextView)findViewById(R.id.textTimer);
textTimeToLine = (TextView)findViewById(R.id.textTimeToLine);
Button button = (Button) findViewById(R.id.buttonSync);
button.setOnLongClickListener(new OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
StartLine2.startTime = pTime + 1000*60*5;
return true;
}
});
}
You can't do this via XML. Instead, use:
Button button = (Button) findViewById(R.id.<your_id>);
button.setOnLongClickListener(new OnLongClickListener() {
#Override
public boolean onLongClick(View v) {
// TODO Auto-generated method stub
return true;
}
});
Make sure this code comes after setContentView() has been called.
Also, make sure that the android:longClickable property is set to true.
In your XML, the ID is set to buttonSync, while in the Java code you're using button_sync. This is the reason for your NullPointerException, as you don't have a button called button_sync.
public class GameScoreFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
Log.v("TTT", "GameScoreFragment.OnCreateView()");
View viewScore = inflater.inflate(R.layout.gamescorelayout, container, false);
// set onLongClick listeners for both buttons
// when player long presses any of the two buttons, scores are reset
Button tempButton = (Button) viewScore.findViewById(R.id.id_button_pone_score);
tempButton.setOnLongClickListener( mLongListener );
tempButton = (Button) viewScore.findViewById(R.id.id_button_ptwo_score);
tempButton.setOnLongClickListener( mLongListener );
return viewScore;
}
// define a variable mLongListener to hold the listener code
// and then use mLongListener to set the listener
// if we don't define the variable, then we will have to write the listener code at two places (once for each button)
private View.OnLongClickListener mLongListener = new View.OnLongClickListener() {
#Override
public boolean onLongClick(View pView) {
//reset player scores
GameFragment tempGameFragment = (GameFragment) getFragmentManager().findFragmentById(R.id.id_gamefragment);
if (tempGameFragment != null)
tempGameFragment.resetPlayersScore(false);
return true;
}
};
}
Can any one tell me? how can i use the same button for two Action?
Like em using one button in my activity that calculate some values and after calculating the when i again press same button then reset the all fields. Like in this Application
http://www.craziness.com/games/play-love-tester/ when i test the love by pressing the button
then i again press the same button then all fields reset.
what should i use in my activity for the above problem?
You can create a global variable which indicates the state of the program and then change this value when needed. In the OnClickListener of your Button you create an if statement which checks this variable and does the needed things for the associated value.
Example:
public class MainActivity extends Activity {
private int state = 0;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (state == 0) {
// State 1
}
else if (state == 1) {
// State 2
}
else {
// Default state
}
}
});
// Rest of your code including state changing part
}
}
You can do it by changing the button text.
If you do not want that someone sees the text change. Test (example "click" and the other state "click " (1 blank at the end) or another solution.
....
Button bt = (Button) findViewById(R.id.button);
bt.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// todo: check for expected instance (Button)
Button btc = (Button)v;
String bText = btc.getText().toString();
if (bText == "open") {
btc.setText("close");
}
else if (bText == "close") {
btc.setText("open");
}
}
[...]
You can do so by using a toggle button.
In your xml file add a toggle button
<ToggleButton
android:id="#+id/tbtn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=""
android:textOff="Reset"
android:textOn="Calculation"
android:background="#drawable/icon"/>
Java file
public class Reviews extends Activity implements OnClickListener {
private ToggleButton tbtn;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tbtn = (ToggleButton) findViewById(R.id.tbtn);
tbtn.setOnClickListener(this);
public void onClick(View view) {
if (tbtn.isChecked()) {
//calculate the result
}
else {
//Reset your global calculation variable;
}
}
}
}