For loop not terminating - Android - android

I don't know why but my for loop won't 'stop' when its reached the truth of the termination statement.
for(int i = 1; i < 11; i++){
edittext.setText("");
EasyGame();
//if(i==10){
//Game.this.finish();
//}
}
EasyGame() is an arithmetic method, just adds two numbers together. I tried using the if statement shown above, but it still wouldn't do anything, and if it did it would call finish() after the first question!
If someone would be kind to help me I would be grateful.
EDIT:
public void EasyGame(){
Random rand = new Random();
final int a = (int) rand.nextInt(20)+1;
final int b = (int) rand.nextInt(20)+1;
String aString = Integer.toString(a);
String bString = Integer.toString(b);
String display = aString + " + " + bString + " =";
questionLabel.setText(display);
c = a + b;
}
that for loop is inside a switch/case, which deals with onClick() for buttons

Very difficult to say without seeing more code, but what you have posted alone is inherently flawed because you're trying to continuously update a UI element within a loop. If that loop is running on the UI thread, then the system isn't going to be able to redraw any UI elements such as your edittext until the loop (and whatever containing callback method) exits.
Therefore, when you say "I tried using the if statement shown above, but it still wouldn't do anything, and if it did it would call finish() after the first question!" I make the assumption that you're believing that the loop is only iterating once because you only ever see edittext display whatever is passed in the last ever .setText() call.

I dont see anything wrong with that code. The only possible problem is that your counter is being decremented somewhere (for example inside EasyGame();), or the problem is somewhere else

In the lack of provided code, I assume that your indefinite loop is happening inside EasyGame() method

The loop probably only runs once, and then it gets halted by a never ending loop in EasyGame().
Note: Don't use initial capitalized letters for methods, it's confusing.

I agree with Trevor Page, and i'll try and clarify :
your code, if it runs on a callback on the UI thread, could be calling itself by generating a callback when you are clearing the first textView or modifying the second.
Also, what do you mean by 'it won't stop' ? I don't quite see what you are trying to do here, since you erase 10 times the content of a textView and replace 10 times the content of another one.

Related

Is it possible to see which functions are called in Logcat?

I know, there is a way to see which functions are called in log-cat is to write a log message on top for every function like this
#Override
protected void onDestroy() {
super.onDestroy();
Log.d("myTag","onDestroy function is called!");
// some logic
}
But it becomes irritating when you have more function.
So, I wonder if there is a way to see which functions are called in adb-logcat without writing log messages for every function.
I hope they can be fetched from somewhere in the stack but I couldn't find it.
You can try Hugo. In that case you have to annotate your methods with #DebugLog only. Then Hugo will generate logs for you (and will print out arguments and return value!). Example from GitHub:
#DebugLog
public String getName(String first, String last) {
SystemClock.sleep(15); // Don't ever really do this!
return first + " " + last;
}
And log output:
V/Example: ⇢ getName(first="Jake", last="Wharton")
V/Example: ⇠ getName [16ms] = "Jake Wharton"
Instead of printing log in every function. I (or most of the people) would suggest you to put debug.
To use debug first create breakpoints inside every function you want to check. To apply breakpoints simply left click in the area to the left of your code (refer image the pink circle represents a break-point).
Then to use Debug you have to press this button after successfully running your application.
As soon as the first method is called your application will pause at the break-point, then you can use F8 (or F6 if you are using eclipse settings) to move to next line, to move to next break-point you can press F9(or F8 if you are using eclipse settings). this way to can check all the functions being called.
This break-point method is really helpful if you just want to make sure that a particular function is being called.
Other than this if you still insist to know the details of all the functions you can store the stacktrace.
final StackTraceElement[] trace = new Throwable().getStackTrace())
StackTraceElement STrace = trace[1];
String className = STrace.getMethodName();

Does break statement inside if inside while finish "while loop" completely or only immediate "if"?

I have this code, that caused me error. The code goes through list and sees if any user is logged in, if it is logged in it counts which user it is - first or second.
When i placed that break statement inside if, the loop only found the first user and did not do anything about 2nd user - the entire loop was ending! How so? I thought the break only works for the immediate block it is placed within, i.e. if break is in if{}, it breaks out of this if and the code execution continues.
Does break statement end even the outside loops?
do {
if (userlogin){
if(how_many_logged_in == 0){
name1.setVisibility(View.INVISIBLE);
}
else if(how_many_logged_in == 1){
name2.setVisibility(View.INVISIBLE);
break ; //this is confusing - where does it break from?
}
}
} while (condition);
As per the java language specification, break ends abruptly the innermost enclosing switch, while, do, or for control structure. So, if/then/else are simply ignored.
As this says,break is used to leave most nearest loop,for example:
while(***){break;}
do{break;}while(***)
switch
for
,but doesn't work in statements like if.

Robotium Solo - wait for broadcast

I want to create a condition to wait for a broadcast upon a button press
right now I am just doing solo.sleep(10000)
but I dont want to sleep solo for nothing
How do I formulate the condition "broadcast received" ?
Ok explanations
Robotium Solo is an instrumentation framework with nice api
It has a method called "solo.waitForCondition(Condition, int timeout)"
I want to formulate (the word formulate means say what i want to say in correct words)
the correct condition that will tell me that the broadcast was indeed received
I want to write some code (I don't know which exactly) to know that the broadcast was indeed sent
for example, if i want to know that a button is now visible i would write
solo.waitForCondition(new Condition(){
public boolean isSatisfied(){
Button b = getActivity().findViewById(R.id.myButton);
return b.getVisibility() == View.VISIBLE;
}
}
now back to my question - What (not how, but what) do I write in order to know for sure that the broadcast was sent inside the isSatisfied method
I suppose you meant that you don't want to sleep for 10 seconds, if you get the broadcast earlier. What you can do is
long beginTime = new Date().getTime();
while (new Date().getTime() - beginTime < 10000) {
solo.sleep(500);
if (conditionMet) {
// Do something
break;
}
}
This way you can do these checks on smaller intervals.
Ok, so in fact this is more or less how waitForCondition is implemented. Unfortunately I don't think you can listen for events with robotium. What you can do is monitor the view hierarchy. In your case, there should be some difference to the views that is triggered when the button is clicked, so that is what you need to check for in the Condition (and your example does that).
This is if you don't want to edit the code you are testing. If you are willing to change the code, you can add an onClickListener() and in that you can set a view's Tag to a boolean for example. Later in robotium you can check for that tag for being set. This is however not good way to do it, because you are adding more code just for the sake of the tests.

Android TextView Slow Using append() Hundreds of Times - Solution?

I have a source code editor for Android, and I have a line numbers counter that's to the left of the main EditText with source code inside it.
I have the following function I use for updating the line numbers text view:
String lineDelimiter = "\n";
public void updateLineNumbers(){
int lines = textBox.getLineCount();
lineNums.setText(1 + lineDelimiter);
for(int i = 2; i < lines; i++){
lineNums.append(i + lineDelimiter);
}
}
All this is fine, but the problem is when you have a document with say 200 odd lines you start to notice a little delay when adding lines. Is this cause Android TextView's setText/append methods are a little slow? Or is it the concatination that's causing the delay?
I've also made a similar function that appends a line number when the user adds a line number, and vice versa, as opposed to clearing the TextView and adding each line numbers again like the function above does. But this function still lags the app when the user adds/removes line(s).
How can I stop this? I can't think of what to do and it's stressing me out because it's lagging my app and rendering it unusable for large files! :(
Thanks for looking!
SOLUTION
I've found a way to have fast line numbers, which is to use a custom TextView with onDraw(Canvas canvas) overriden and to draw them that way which results in lag-free line numbers :).
Is this cause Android TextView's setText/append methods are a little slow? Or is it the concatination that's causing the delay?
Use Traceview and find out.
Off the cuff, I would imagine that calling append() a whole bunch of times on a TextView will be vastly slower than calling append() a bunch of times on a StringBuilder, then calling setText() once on the TextView.
How can I stop this?
Don't handle line numbers that way. For example, put a TextView to the left of the EditText, and put your line numbers in the TextView, one per line.

parseInt crashing android app

So I'm trying to make a calculator app (just to get a hang of android development), and I noticed with some testing that the parseInt conversion from "String tack1" is causing the app to crash. Can someone tell me why? I can't seem to figure it out and I've been searching the internet for quite a while now. (hehe I'm a noob so please go easy) In the code below, I've modified a couple lines to make it seem obvious what it's supposed to print however it still crashes. Here's the code:
equals.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
oC = 1; //operator checker is on 1 (for plus)
switch(oC){ //check for operator clicked
case 0: break;
case 1:
tack1 = "1"; //INSERTED THIS TO MAKE OUTPUT OBVIOUS
tack1 = tack1.trim(); tack2 = tack2.trim(); //INSERTED BEFORE TO DEAL WITH WHITESPACE
numOne = Integer.parseInt(tack1); //CRASHES HERE
answer.setText(numOne);
modeChecker = 0; oC = 0;break;
NOTES ON PROGRAM(some of comments repeated and other stuff as well):
The tack1 = "1"; is to make output obvious
The tack1.trim() is to deal with whitespace
Yes whatever is in tack is a number and an integer (not even a negative integer)
Yes numOne is an integer and is defined wayy above (not in code listed here)
Sorry the indents are all messed up(after case 1) because of the comments I added
This is a section of my onClick method, so closing brackets aren't included in here.
Can someone please help me?
THANKYOU :D
I'd be willing to bet it's actually crashing on the following line AFTER the call to parseInt.
You're calling setText(int) on your TextView. When you pass an int to this method, that int is a pointer to a string resource...you're probably expecting an auto-conversion to a string. Since you are passing it an int that is generated in your application, it's extremely unlikely that this int also points to a string resource in your res/values/strings.xml file. What you really want to do is change numOne to a string first, which you can do inline:
Change
answer.setText(numOne);
to
answer.setText(String.valueOf(numOne));
and you're good to go.

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