I am developing a keyboard in Android (a braille keyboard, specifically). For those of you who do not know, braille is composed of six dots, and combinations of these dots form symbols. I wrote a keyboard using the KeyboardView class with the basic listener, but the problem is this: the default listener only allows for one key to be pressed at a time. To form the letter l requires three dots (dots 1, 2 and 3). I have to press each key individually, followed by the spacebar to write the letter. I would like the keyboard to function in a different way; all dots can be pressed simultaneously, and when the dots are released, the letter is written.
Am I right when thinking this is impossible with the listener bundled with KeyboardView? If I rewrite the onTouch routine in the KeyboardView, would this latter functionality be possible? Does the OnTouch function detect multiple action_down events simultaneously? I was thinking that if this is possible, I can determine the x-y coordinates of the press, loop through the keys on the keyboard, and determine which keys are being pressed. If this is not possible, will I have to go a step below this and write onTouch for a basic view?
Thank you so much.
If you want to make some quick tests to a keyboard, like a new key layout or a new predictive text algorithm, KeyboardView is fine. If you're doing anything more complicated KeyboardView just doesn't have any real flexibility. None of the major keyboards use it (and I know that for sure, I wrote one of them and have talked to engineers at the others).
You could rewrite onTouch or put in a touch listener on the existing keyboard view, but then you're going to have to do a lot of work inside of their framework, such as hit testing to determine what key is touched. At that point its probably easier to just write your own from scratch. I almost guarantee you will at some point anyway if you go all the way to a commercial product.
You can use onTouch to get multiple fingers down, but it won't be on ACTION_DOWN. You get an ACTION_DOWN for the first finger down, then an ACTION_POINTER_DOWN for each additional finger. This is how it works for any view. Then any motion on any finger will generate an ACTION_MOVE. When fingers are released you get an ACTION_POINTER_UP for all fingers until the last, which gets an ACTION_UP.
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I have to implement a two fingers tap.
For example I have a listView with multiple items, which already have a click listener for each row and touch listener. Now I have to do something if the user put two fingers on a row.
How can I do this?
Any suggestion is appreciated.
I believe just the gesture API only support single touch.
You basically have to override `onTouchEvent, and play with e.getPointerCount() and check the time between the ACTION_POINTER_DOWN and ACTION_POINTER_UP. You will probably also think about the case where the two touches actually do not come at the exact same time or leave the screen at the exact same time either.
Try this
Android multi-touch support
Or
http://www.rbgrn.net/content/367-source-code-to-multitouch-visible-test
android imageView: setting drag and pinch zoom parameters
This may help you.
Not sure what you mean by 2 fingers tap. If you mean a double tap (one finger, 2 taps) , I recommend this:
http://mobile.tutsplus.com/tutorials/android/android-gesture/
But if you are referring to 2 different fingers tapping once, would not recommend doing that a 2 finger tap because it goes against the Android design guidelines. If anything it is recommended to do a long press, which can easily be implemented overriding the onLongClick() method.
But if you really do not want to listen to me because you think I am stupid. You would essentially need to implement your own multi touch gesture. Here is one example:
http://www.zdnet.com/blog/burnette/how-to-use-multi-touch-in-android-2-part-2-building-the-touch-example/1763
FYI, please be aware of what android version you want to support.
What is the best way to touch two buttons at the same time? I am working on an app that has buttons, like a D-pad and a jump button, to move your character around. Right now I am just using normal buttons and handling them with an OnClickListener. I am having problems when I am running and need to jump at the same time, or if I am running to the right, then want to go left without having to pick my finger up. I know this is possible because it works greats on game like Sonic CD and some others. Any help would be greatly appreciated.
OnClick fires only on release. Instead use the touch event handlers so that when they touch occurs, you get the events. However, note that not all devices have multitouch, and thus not all of them will be able to handle the double-touch case correctly. They will provide touch events, but not two of them. Also note that you may receive multiple "pointers" within a touch event, and will have to decide which is "yours" for each button if that matters.
Good day to all!
I'm trying to implement a voice over for Android (like iPhone), but a specific application (not the entire operating system)
Imagine a screen with six buttons, so they occupy the entire activity, distributed equally in size.
When I "walk" with my finger on the screen, I want to give focus to the button and capture the event when the button has focus and let the focus as well.
Conclusion: As I flick on the screen and if it is over a button, the focus button. if I continue to drag the finger, give the focus to another button without taking your finger off the screen.
Can anyone help me? Sorry for bad English.
I don't think you can use the Android Button class for this, but instead do a custom view, draw six rectangles, and write an onTouchEvent method that determines what sound to play based on where the user's finger is. See the Sudokuv4 example at http://pragprog.com/book/eband3/hello-android for some code you can use.
Well you have to know positions of buttons. You can use basic view functions to get positions (getLeft(), and so on...)
After that you have to implment onTouchListner for Activity. Within you have to check where Event.x and Event.y pointers are and set foucs to specified view. After pointers move from specified view you set focus to false.
Hello i make appliction like Drum Studio. I need make support for touch more one button at once. For example: User touch button1(AND HOLD IT!) it play sound, but user still hold its, user click another button and it play sound too. How make it programmatically? By default onTouch or onClick use, if 1 button pressed, another buttons not react before button isn't released.
Use the onKeyDown() events to trigger each response and onKeyUp() events to finish them.
http://developer.android.com/reference/android/view/KeyEvent.html
http://developer.android.com/reference/android/view/KeyEvent.Callback.html
For touchs, you can use the OnTouchListener
http://developer.android.com/reference/android/view/View.OnTouchListener.html
and determine the kind of touch by the MotionEvent:
http://developer.android.com/reference/android/view/MotionEvent.html
To clarify my response: To make a sound while holding one button, you can start the sound when the ACTION_DOWN action in the MotionEvent event is triggered and stop it with the ACTION_UP action of the same event.
Create a class extending View where you're holding all your buttons.
Override the onTouchEvent vor that class.
Switch between the different actions.
Use event.getX() and event.getY() to figure out where the touch event was originated.
Check which button is located at that position
Play the sound accordingly.
You cannot touch two separate Views at the same time, even if multi-touch is supported on your device. If you touch Button1 first, all subsequent MotionEvents (including ones with separate pointer IDs) are bound to that View.
Unless you're using a dedicated game engine like AndEngine that has this sort of functionality built in, your only option is to capture all the MotionEvents yourself (most easily with an empty ImageView covering your entire screen) and route them to the appropriate Views based on their screen coordinates. This can get tricky, especially with multiple touch pointers, but the Android UI framework does not natively support the kind of multi-touch you require.
You definitely want to be using Android 2.0 or higher - previous versions don't support multitouch.
Check the pid in your onTouch - 0 is a single touch, 1 is the second.
Hi Here i want to solve the problem regarding multitouch in android. Is this possible to fire events of 2 buttons together if this is possible then how can i do this. please help regarding this. In my game application i want to do something after pressing two buttons together. How can i do this.
I don't think that it is possible to aggregate two events to a single one oob. But it shouldn't be to hard to determine if two buttons were pressed simultaneously by using a OnTouchListener you bind to the parent element of the two buttons.
When an event is thrown and the onTouch() method is called. You got a bunch of arguments related to the event, like what kind of event it was (Action_Down, Action_Move, Action_Up etc.). You also get the information if the action was performed by the first oder by the second finger so this should give you the option to decide whether both buttons were touched.
Here you can find a nice tutorial about multi touch support on Android.