How do I implement this condition as shown in this image.
That's just in 2..4, i.e. in the integer range from 2 to 4, including the 4.
The ≤ is just some hint text provided by the IDE, similar to how you can see argument names in function calls - it's not part of the code, it's not really there. They added it to make it clearer what the .. operator does (vs until)
This might be because they're introducing a new operator, ..< which seems intended to replace until, or maybe they've been there a while! You can turn them on and off here in the settings:
I really hope this question has not been answered everywhere else already but every search seems to focus on listeners and other uses of a button array but i want to also use it for formatting all buttons at the same time (activate, deactivate etc)
So here is what I have tried;
val buttons = arrayOf(btn1,btn2,btn3,btn4)
This will work, BUT will only change a single button
buttons[0].isEnabled=true; //
Then this is the bit that I am struggling with;
buttons[0..buttons.size].isEnabled=true;
The response is basically that it expects a single number and not a range.
I also tried;
buttons[].isEnabled=true;
The response is that it requires an index
I also tried
buttons.isEnabled=true;
This of course will not resolve properly
My key question really is can I apply formatting/state changes to all using an array or will I always have to do it for each button in turn?
I think it would be possible to create a loop but that isn't the route I wanted to follow here if there is an alternative
Don't think there is a way mate. You gotta loop and regardless of what syntatic sugar a language has in the end its still a for loop.
You could do:
buttons.forEach {
it.isEnabled = true
}
I'm taking over care and feeding of an existing React-native app. There's a part of the app that takes a picture, which results in the message "Transform with key of "perspective" cannot be zero: {"perspective":0}". (This happens in the Android emulator.)
In the existing code, there's no place that designates a perspective. I'm curious what might be implicitly expecting this.
I figured out what was happening. The code was rendering a FlipCard (#see react-native-flip-card) FlipCard takes an attribute "perspective," whose default is zero. Setting it to something other than zero saved the day: ...<FlipCard perspective={0.5}...>
Hope this helps someone.
I'm designing a spaceship game in App Inventor. I have a label (lblScore) update when the ship is hit each time. When the ship is hit 3 times, I want the code inside that to execute yet it doesn't work. I've tried multiple variations of this, such as setting it to lblScore.Text instead. Any idea's on how I can address the issue?
Is the lblscore a label?
If it is all you need to do is have a collision block saying whenever the spaceship gets hit, set lblscore = lblscore + 1
This should fix your issue but I would like to see all of your blocks
Do you increment your lblScore in the Ship.CollidedWith event?
If yes, you should move your if statement there, but instead of using the lblScore component as currently, you should better use the lblScore.Text property instead.
Probably it would help us to help you, if you provide a screenshot of your Ship.CollidedWith event...
I want to know is there any method or any link or tutorial to perform redo undo operation in Android edittext. If any one knows than please let me know.
Quick note on the Antti-Brax/Divers(Kidinov) solution. It works great, except if you try to use it with a TextView post-API 23, you'll run into problems, because guess-what, Google actually added a hidden UndoManager (android.content.UndoManager) and didn't document it or make it obvious it was there. But if you have a hard/bluetooth keyboard in Marshmallow or Nougat and hit ^Z or SHIFT-^Z, you'll get undo/redo.
The problem comes if you're already using Antti-Brax's class with an EditText, and you also hook it to ^Z and shift-^Z, you'll run into problems with anyone using a hard keyboard. Namely the ^Z will trigger BOTH the native and Antti-Brax's undo, leading to two undos simultaneously, which isn't good. And after a few of them, you'll probably get a Spannable out of bounds crash.
A possible solution I found is to subclass the TextView/TextEdit/whatever and intercept the undo/redo calls from the TextView so they don't run as follows:
#Override
public boolean onTextContextMenuItem(int id) {
int ID_UNDO, ID_REDO;
try {
ID_UNDO = android.R.id.undo;
ID_REDO = android.R.id.redo;
} catch (Resources.NotFoundException e) {
ID_UNDO = 16908338; // 0x1020032
ID_REDO = 16908339; // 0x1020033
}
return !((id == ID_UNDO) || (id == ID_REDO)) && super.onTextContextMenuItem(id);
}
Those magic id numbers were found here, and are used only as a backup if the android.R.id.undo values aren't found. (it also might be reasonable to assume that if the values aren't there the feature isn't there, but anyway...)
This is not the best solution because both undo trackers are still there and both are running in the background. But at least you won't trigger both of them simultaneously with ^Z. It's the best I could think to do until this gets officially documented and the getUndoManager() methods of TextView is no longer hidden...
Why they made a feature you can't turn off (or even know if it was there or not) "live" in released Android I can't say.
I just opened an issue on Android's issue tracker if anyone wants to follow this.
There is an implementation of undo/redo for Android EditText in
http://credentiality-android-scripting.googlecode.com/hg/android/ScriptingLayerForAndroid/src/com/googlecode/android_scripting/activity/ScriptEditor.java
The code works but does not handle configuration changes properly. I am working on a fix and will post here when it is complete.
My Google search was :-
android edittext onTextChanged undo
I know this is an old question, but as there is no accepted answer, and this is an issue I've tackled myself from many angles, I'd like to add my solution in case it helps anyone. My answer is probably most relevant to large (1,000words+) volumes of text editing apps that require this feature.
The simplest way to resolve this problem is to make periodic copies of all text on screen, save it to an array and call setText() every time the Undo method is called. This makes for a reliable system, but it isn't ideal for large (i.e. 1,000words+) text editing apps. This is because it:
Is wasteful. It could be that only one word changes in a two thousand word document, so that's one thousand, nine hundred and ninety nine words needlessly committed to memory.
Can lead to performance issues, as some low-tier hardware struggles with rendering large amounts of text. On some of my test devices, this method can lead to freezes of a few seconds whenever Undo is called.
The solution I currently use is comparatively complex, but I've published the results in a library here.
Essentially, this library saves a copy of text as soon as a user begins typing, and then another copy of text once they've stopped typing for a set amount of time (in my case, two seconds). The two text strings are then compared, and the altered section of text returned, the indexes where the alterations occured, and details on whether or not the change was an addition of new text, a deletion, or a replacement of old text with new text.
The net result is that only the necessary text is saved, and when Undo is called, there is only a local delete(), replace() or insert() call, which makes for much faster operations on large text fields.
Here is the undo/redo implementation that was linked to from Gary Phillips' answer extracted into a reusable and universal undo/redo plugin for any widget that descends from a TextView. I added some code for persisting the undo history.
http://code.google.com/p/android/issues/detail?id=6458#c123
Hope this helps.
To preserve EditText Styling with regards to undo:
You can create an ArrayList<EditText> or ArrayList<String> (String containing html text) to store your last 10 (for example) actions. So ArrayList [0] would contain html text from your first action and ArrayList [9] would contain html text from your very last action. Each time the user taps "undo" in your app, you would apply ArrayList [size()-1] to your EditText and then remove ArrayList [size()-1] from your Array.