Develop Reference

Are these TWO pieces of code doing the same thing?

I am working on an Android Application which saves data to an SQLite database. I've removed the first piece of code as I believe the second piece of code is already doing the same thing. I have run a few tests and everything still seems to be working perfectly. Is there any further purpose for the first piece of code?
First piece of code....
Cursor res = myDb.getRoutineForCurrentDay(currentDay);
if (res.getCount() == 0) {
} else {
//data found, show on screen
StringBuffer buffer = new StringBuffer();
while (res.moveToNext()) {
buffer.append("Id : " + res.getString(0) + "\n");
buffer.append("Day : " + res.getString(1) + "\n");
buffer.append("Act : " + res.getString(2) + "\n");
buffer.append("Slot : " + res.getString(3) + "\n");
}
}
ImageID = 0;
break;
Second piece of code....
private void getRoutine() {
Cursor res = myDb.getRoutineForCurrentDay(currentDay);
if (res.getCount() == 0) {
} else {
//data found, show on screen
while (res.moveToNext()) {
int ActID = res.getInt(2);
int SlotID = res.getInt(3);
ImageView slot = (ImageView) findViewById(SlotID);
slot.setImageResource(ActID);
}
}

Well, the second piece of code sets up an Imageview and populates it, while the first piece of code only processes the info as text.
My guess would be someone wrote the first piece of code just to check whether or not the local DB contains the correct values.
The second snippet should be all you need.

How to replace the word in the string by using replace in Android?

I want to replace one word in the String by using substring. But it seen didn't work.
for example: The string is 0000 , and I want to replace the first word from 0 to 1.
It should be 1000. but it doesn't.
The code is like the following
String WorkStatus = "0000";
if(WorkStatus.substring(0, 1).matches("0"))
{
WorkStatus.substring(0, 1).replace("0", "1");
Log.d(TAG, "WorkStatus.substring(0, 1) = " + WorkStatus.substring(0, 1) + "\n");
Log.d(TAG, "WorkStatus = " + WorkStatus + "\n");
}
It didn't work , the string always show 0000. And what I want is "1000"
Do I missing something ?

use this
String WorkStatus = "0000";
//You use matches, while you might as well use equals
if (WorkStatus.substring(0, 1).equals("0")) {
//reassign workstatus to workstatus where the first entry is a '1' + the last three chars "000"
WorkStatus = WorkStatus.substring(0, 1).replace("0", "1") + WorkStatus.substring(1, WorkStatus.length());
Log.d(TAG, "WorkStatus.substring(0, 1) = " + WorkStatus.substring(0, 1) + "\n");
Log.d(TAG, "WorkStatus = " + WorkStatus + "\n");
}
You didnt assign the modified string to WorkStatus
Another possibility is converting the string to a char[] and replacing the index, instead of working with substrings.
String WorkStatus = "0000";
char[] chars = WorkStatus.toCharArray();
if (chars[0] == '0') {
chars[0] = '1';
WorkStatus = new String(chars);
}
If you want other chars to become 1 instead of zero, alter the chars[0] into chars[index], where index is the index you want to change from 0 to 1
Or, even easier, use a StringBuilder:
int yourIndex = 2; //your index which you want to check for 0 and change to 1
StringBuilder sb = new StringBuilder("0000");
if (sb.charAt(yourIndex) == '0')
sb.setCharAt(yourIndex, '1');
WorkStatus = sb.toString();

method replace has a return value of the string after replaced
you shuold resign the result to the String
WorkStatus=WorkStatus.substring(0, 1).replace("0", "1")+ WorkStatus.substring(1, WorkStatus.length();

if you asign it to a new variable like the below code, you can get what you needed.
String newWorkStatus=WorkStatus.substring(0, 1).replace("0", "1")+WorkStatus.substring(1);
Log.d("LOG", "WorkStatus.substring(0, 1) = " + WorkStatus.substring(0, 1) + "\n");
Log.d("LOG", "WorkStatus = " + WorkStatus + "\n");
Log.d("LOG", "New WorkStatus = " + newWorkStatus + "\n");

WorkStatus.substring(0, 1).replace("0", "1"); returns 1, you should use StringBuilder instead of String.
My solution:
StringBuilder WorkStatus = new StringBuilder("0000");
int pos = WorkStatus.indexOf("0", 0);
if (pos != -1) {
WorkStatus.replace(pos, pos + 1, "1");
}
System.out.print(WorkStatus);

How to insert a log in LogCat that when I click on it jumps to its line in code?

I want to insert a log in LogCat that when I click on it jumps to its line like some error logs that are generated by system.
Is it possible?

I found it:
public static void showLogCat(String tag, String msg) {
StackTraceElement[] stackTraceElement = Thread.currentThread()
.getStackTrace();
int currentIndex = -1;
for (int i = 0; i < stackTraceElement.length; i++) {
if (stackTraceElement[i].getMethodName().compareTo("showLogCat") == 0)
{
currentIndex = i + 1;
break;
}
}
String fullClassName = stackTraceElement[currentIndex].getClassName();
String className = fullClassName.substring(fullClassName
.lastIndexOf(".") + 1);
String methodName = stackTraceElement[currentIndex].getMethodName();
String lineNumber = String
.valueOf(stackTraceElement[currentIndex].getLineNumber());
Log.i(tag, msg);
Log.i(tag + " position", "at " + fullClassName + "." + methodName + "("
+ className + ".java:" + lineNumber + ")");
}
Its usage:
showLogCat("tag", "message");

The important thing is to insert "(X:Y)" in your log message, while X is your desired file name and Y is your desired line number in X. (I learned it from #breceivemail's answer). So try:
public static void log(final String tag, final String msg) {
final StackTraceElement stackTrace = new Exception().getStackTrace()[1];
String fileName = stackTrace.getFileName();
if (fileName == null) fileName=""; // It is necessary if you want to use proguard obfuscation.
final String info = stackTrace.getMethodName() + " (" + fileName + ":"
+ stackTrace.getLineNumber() + ")";
Log.LEVEL(tag, info + ": " + msg);
}
Note: The LEVEL is the log level and can be v, d, i, w, e or wtf.
Now you can use log(tag, msg) instead of Log.LEVEL(tag, msg).
Example:
MainActivity.java:
...
public class MainActivity extends BaseActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
log("Test Tag", "Hello World!");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
...
...
The output:
12-30 14:24:45.343 ? I/Test Tag: onCreate (MainActivity.java:10): Hello World!
And MainActivity.java:10 automatically would be a link and you can click on it!
You can also assign following value to info variable if you want more verbose log:
final String info = stackTrace.getClassName() + "." + stackTrace.getMethodName() + " ("
+ fileName + ":" + stackTrace.getLineNumber() + ")\n";
So the output of above example would be:
12-30 14:33:07.360 ? I/Test Tag: com.example.myapp.MainActivity.onCreate (MainActivity.java:11)
Hello World!

Please use this Tree with Timber.
class MyLinkingTimberTree : Timber.DebugTree() {
override fun createStackElementTag(element: StackTraceElement): String? {
return makeClickableLineNumber(element)
}
private fun makeClickableLineNumber(
element: StackTraceElement
): String {
val className = element.fileName
val methodName = element.methodName
val lineNumber = element.lineNumber
val fileName = element.fileName
val stringBuilder = StringBuilder(className)
.append(".")
.append(methodName)
.append(" (")
.append(fileName)
.append(":")
.append(lineNumber)
.append(") ")
return stringBuilder.toString()
}
}
And then just instantiate it like this:
class MyApplication: Application() {
override fun onCreate() {
super.onCreate()
if(BuildConfig.DEBUG) {
Timber.plant(MyLinkingTimberTree())
}
}
}
Then just use Timber normally:
Timber.d("Currently Signed in:")
And this is the result. Nice, isn't it? I hope you enjoy using it as much as I enjoyed making it! ;)

Yes you can do it .. Follow the example as answered on SO - logging

To answer the question in a simple way:
respecter cette règle :
{FileName}.{ext}:{LigneNumber}
e.g. MainActivity.java:10
which gives a sample as below
Log.d(TAG, "onResume: MainActivity.java:10");
I hope this will help you

This isn't exactly an answer to the question, but perhaps it's a "close enough" workaround.
Highlight the log text
Press CTRL-SHIFT-F
Double-Click on the search result.
If the text is highlighted before you press CTRL-SHIFT-F, then you don't need to type or copy/paste it in.
If your searches tend to produce too many results, you can use live templates to make unique logcat entries:
Create a live template to insert the Class, Method, and Line-Number (at the time of writing). I use "logi." Yes, the line number will become less and less accurate as you continue to write, but it can still function as a way to make your log entries more "findable."

How can I write a regular expression for this in android?

I am having a string(number) with special characters. I want to search for a sub-string(comprising of digits only) & also I want to detect the starting index & ending index of matching sub-string in the string.
For example: main string: (+91)-1231212 1231
Sub-string to search: 1212
Currently I am using the following code to do this but in place of 1212,it searched for 12312. For other cases, it works fine.
String sss0 = "1212";
String sss1 = "(+91)-1231212 1231";
sss0 = sss0.replaceAll("[^\\d]","");
System.out.println("*************************"+sss0);
String ptn = "" + sss0.charAt(0);
for(int jj=0; jj<sss0.length()-1; jj++){
ptn += "[^" + sss0.charAt(jj) + sss0.charAt(jj+1) + "]*?" + sss0.charAt(jj+1);
}
System.out.println("ptn: " + ptn);
Pattern p300 = Pattern.compile(ptn);
Matcher m300 = p300.matcher(sss1);
if(m300.find()){
System.out.println("start, stop: " + m300.start() + "," + (m300.end()-1 ));
System.out.println("substring: " + sss1.substring(m300.start(), m300.end()));
}
Please help me. Thanks in advance.

Try this :
int start = sss1.indexOf(sss0);
if(start != -1) {
System.out.println("Start : " + start);
System.out.println("End : " + start.length()); //maybe add +1 here depending on what you mean by end index.
}
You can also put this in a loop to find all occurences of the substring.

pseudocode:
pattern = ""
foreach char c in sss0:
pattern += c + "[^0-9]*"
found_substring = match(pattern, sss1)
the idea being to intersperse the literal characters you're looking for with the pattern that you're willing to skip over.

Simple If Statement

I am trying to pass two variables from one screen to another. From the previous screeen you click a button, 1 or 2 and it passes that value on. It also passes the value 2 as the correct value. I know they are both working as I output each variable on the next screen. Here is the code. It always outputs wrong though.
Intent i = getIntent();
Bundle b = i.getExtras();
String newText = b.getString("PICKED");
String correct = b.getString("CORRECT");
TextView titles = (TextView)findViewById(R.id.TextView01);
if(newText == correct){
titles.setText("Correct" + newText + " " + correct + "");
}
else{
titles.setText("Wrong" + newText + " " + correct + "");
}

because you are not comparing the string. you are comparing if both are pointing to same object.
to compare string use
if(nexText.equals(correct))

if(newText == correct)
This will always be false. To compare the contents of two Strings character by character, use the .equals method:
if( newText.equals(correct) )
Using == on objects in Java means you are comparing the values of the memory address stored in these pointers/references. Since they are different String objects, they will never have the same address.

You don't compare Strings this way, rewrite code this way to get things done:
Intent i = getIntent();
Bundle b = i.getExtras();
String newText = b.getString("PICKED");
String correct = b.getString("CORRECT");
TextView titles = (TextView)findViewById(R.id.TextView01);
if(newText.equals(correct)){
titles.setText("Correct" + newText + " " + correct + "");
}
else{
titles.setText("Wrong" + newText + " " + correct + "");
}