How to send out pointer event in Android - android

I'm trying to detect the virtual keyboard height in Android.
I found a similar topic: Get the height of virtual keyboard in Android
It seems the author found a way to detect the height:
I found a way to get it. After I request to open virtual keyboard, I
send pointer event that I generate. their y coordinate starts from
height of device and decreases.
I don't understand how to do that.

I'll be using the code provided at the link that you posted:
// Declare Variables
int softkeyboard_height = 0;
boolean calculated_keyboard_height;
Instrumentation instrumentation;
// Initialize instrumentation sometime before starting the thread
instrumentation = new Instrumentation();
mainScreenView is your base view, your activity's view. m(ACTION_DOWN) and m1(ACTION_UP) are touch events that are dispatched using Instrumentation#sendPointerSync(MotionEvent). The logic is that a MotionEvent dispatched to where the keyboard is being displayed will cause the following SecurityException:
java.lang.SecurityException: Injecting to another application requires
INJECT_EVENTS permission
So, we start at the bottom of the screen and make our way up (by decrementing y) on every iteration of the loop. For certain number of iterations, we will get a SecurityException (which we'll catch): this would imply that the MotionEvent is happening over the keyboard. The moment y gets small enough (when its just above the keyboard), we'll break out of the loop and calculate the keyboard's height using:
softkeyboard_height = mainScreenView.getHeight() - y;
Code:
Thread t = new Thread(){
public void run() {
int y = mainScreenView.getHeight()-2;
int x = 10;
int counter = 0;
int height = y;
while (true){
final MotionEvent m = MotionEvent.obtain(
SystemClock.uptimeMillis(),
SystemClock.uptimeMillis(),
MotionEvent.ACTION_DOWN,
x,
y,
1);
final MotionEvent m1 = MotionEvent.obtain(
SystemClock.uptimeMillis(),
SystemClock.uptimeMillis(),
MotionEvent.ACTION_UP,
x,
y,
1);
boolean pointer_on_softkeyboard = false;
try {
instrumentation.sendPointerSync(m);
instrumentation.sendPointerSync(m1);
} catch (SecurityException e) {
pointer_on_softkeyboard = true;
}
if (!pointer_on_softkeyboard){
if (y == height){
if (counter++ < 100){
Thread.yield();
continue;
}
} else if (y > 0){
softkeyboard_height = mainScreenView.getHeight() - y;
Log.i("", "Soft Keyboard's height is: " + softkeyboard_height);
}
break;
}
y--;
}
if (softkeyboard_height > 0 ){
// it is calculated and saved in softkeyboard_height
} else {
calculated_keyboard_height = false;
}
}
};
t.start();
Instrumentation#sendPointerSync(MotionEvent):
Dispatch a pointer event. Finished at some point after the recipient
has returned from its event processing, though it may not have
completely finished reacting from the event -- for example, if it
needs to update its display as a result, it may still be in the
process of doing that.

Use OnGlobalLayoutListener, it works perfectly for me.

Related

android display a response while user performs a gesture

How to show a response while gesture input is in progress?
I'm using swipe down gesture to reload my WebView.
Using this for gesture detection:How to detect swipe direction between left/right and up/down
Problem
SimpleGestureListener captures the result of user input only. It cannot be used to show a response, e.g. animation, while the user is performing a gesture.
Imperfect inelegant solution:
flaw: Shows animation independent of SimpleOnGestureListener; a response to user gesture input is displayed and gesture input may still fail or vice versa.
private volatile float userTouchY = -1;
// translating WebView every onTouch event call is inefficient.
// only translate when translateYBy value is greater than a threshold.
private float translateYBy = 0;
/**
* Shift webView without animation.
* #param num
*/
private void __shiftWebViewDownBy(int num){
float current = webView.getY();
if(current >= webviewTranslationLimit) return;
current += num;
if(current> webviewTranslationLimit) current = webviewTranslationLimit;
webView.setY(current);
}
#Override
public boolean onTouch(View v, MotionEvent event) {
//Skip everything unless at the content top.
if(webView.getScrollY() > 0) return false;
int action = event.getAction();
if(action == MotionEvent.ACTION_MOVE){
float y = event.getY();
float dif = y - userTouchY;
if(dif < webviewTranslationLimit/10){
//dif less than screenHeight*1/40, ignore input
}else if(dif < -(webviewTranslationLimit/5)){
//swipe up
userTouchY = -1;//not swipe down cancelling
__shiftWebViewTopTo(0);
}else if(userTouchY < y) {
//swipe down
translateYBy += dif;
if(userTouchY == -1){
//userTouchY at the initial value, ignore for this once.
userTouchY = y;
}else{
userTouchY = y;
if(translateYBy > 5 ){
__shiftWebViewDownBy((int)translateYBy);
translateYBy = 0;
}
}
}
}else{
Log.d(TAG,"action not move:" +MotionEvent.actionToString(action));
// Webview shift down should only occur while moving
// Once finger is off,cancel
__shiftWebViewTopTo(0);
userTouchY = -1;
}
boolean result = gestureDetector.onTouchEvent(event);
return result;
}
Writing a GestureListener of a sort from scratch obviously solves the problem and I can simply use Toast to message the user for a failed gesture input, but there ought to be an easier, more readable solution.

Can i use motionEvent .getRawY() with View . getTop()?

Im making a program about the game Go and im trying to write some code to allow a person to place a bead, which really just shows an invisible bead. But after an hour of going back and forth with it i just cant seem to figure out why the Y coordinate of my motionevent always seems 2 rows down from where it needs to be.
My code for filling my array
for(int y=0; y< 9;y++)
{
for(int x=0;x<9;x++)
{
String name="Whitebead" + ((9*y)+x+2); //The +2 is because of a naming problem
WhitePieces[x][y]=(ImageView) findViewById(getResources().getIdentifier(name, "id", getPackageName()));
}
}
My code for handling motion events
#Override
public boolean onTouchEvent(MotionEvent e)
{
if(e.getAction() == MotionEvent.ACTION_DOWN)
{
float X=e.getRawX();
float Y=e.getRawY();
if(X>Board.getLeft() && X<Board.getRight())
if(Y< Board.getTop() && Y>Board.getBottom());
player1.placepiece(X, Y);
}
return super.onTouchEvent(e);
}
And finally my code that resolves which bead to what coordinate
public void placepiece(float X, float Y)
{
int[] pieceindex=resolvePiece(X,Y);
pieces[pieceindex[0]][pieceindex[1]].setVisibility(ImageView.VISIBLE);
}
private int[] resolvePiece(float x, float y) {
int Xindex=0;
int[] oldcoords= new int[2]; //cordinates are like so {xCoord, Ycoord}
int[] newcoords= new int[2];
oldcoords[0]=pieces[0][0].getLeft(); //set the oldcoordinates to the first index
oldcoords[1]=pieces[0][0].getTop();
for(int i=1; i<9;i++) //go through the 9 indexs to find the closest X value
{
newcoords[0]=pieces[i][0].getLeft();
newcoords[1]=pieces[i][0].getTop();
if(Math.abs((int)x-newcoords[0])<Math.abs((int)x-oldcoords[0]))
{
Xindex=i;
oldcoords[0]=newcoords[0];
}
}
int Yindex=0;
oldcoords[0]=pieces[0][0].getLeft(); //Reset oldcoords again
oldcoords[1]=pieces[0][0].getTop();
for(int n=1; n<9;n++) //Go through the 9 indexes for the closest Y value
{
newcoords[0]=pieces[0][n].getLeft();
newcoords[1]=pieces[0][n].getTop();
if(Math.abs((int)y-newcoords[1])<Math.abs((int)y-oldcoords[1]))
{
Yindex=n;
oldcoords[1]=newcoords[1];
}
}
int[] rInt= new int[]{Xindex,Yindex};
return rInt;
}
//////EDIT: Fixed
I figured it out, at the top of the android window is about and inch of space where the title and battery life and stuff go, when you get motion coordinates it takes in the whole screen, where .getTop() only gets from where linear layout Starts. SO instead of using .getTop or.getLeft i used .getLocationInWindow(oldcoord[]) and it places the info i needed into my oldcoord array.
//////EDIT: Fixed I figured it out, at the top of the android window is about and inch of space where the title and battery life and stuff go, when you get motion coordinates it takes in the whole screen, where .getTop() only gets from where linear layout Starts. SO instead of using .getTop or.getLeft i used .getLocationInWindow(oldcoord[]) and it places the info i needed into my oldcoord array.

Multiple finger input for android development

After getting the calculator application to work I decided to try to create pong. There is a box in the center and two paddles on both ends. The phone is horizontal. I have the box bouncing off the walls and the paddle moves with me moving my finger down. My problem is i want to make it two player and i want to have multiple finger input for the game. I want one finger to move paddle 1 and the other to move paddle 2. So far this is my input code
#Override
public boolean onTouchEvent(MotionEvent ev) {
final int action = ev.getAction();
switch (action) {
case MotionEvent.ACTION_MOVE: {
// Find the index of the active pointer and fetch its position
float p1y = ev.getY();
if(ev.getX()<300)
{
player1y = p1y;
}
if(ev.getX()>300)
{
player2y = p1y;
}
//player1y = p1y;
invalidate();
break;
}
}
return true;
}
it resides in my surfaceview class. How can i modify the input method or completely get rid of it and change it to accomplish my goal? Also sorry about my variables. Eclipse crashes a lot on me and my laptops touch panel tends to move my cursor so shorter variables seemed viable. p1y is the y of the touch. and player1y and player2y is the y positions of the player1 and player2 paddle.
A MotionEvent can hold multiple pointers. Use getPointerCount() to see how many pointers are touching the screen in the current event. There are alternate versions of getX and getY that take an index from 0-getPointerCount() - 1.
In a more complex app you would want to track fingers by pointer ID, but for something this simple where you are using a cutoff point on the screen you could do something like this in your ACTION_MOVE case:
int pointerCount = ev.getPointerCount();
for (int i = 0; i < pointerCount; i++) {
float x = ev.getX(i);
float y = ev.getY(i);
if (x < 300) {
player1y = y;
} else if (x > 300) {
player2y = y;
}
}
This post from the Android Developers Blog might help if you'd like more information: http://android-developers.blogspot.com/2010/06/making-sense-of-multitouch.html

Android - Moving a single image

Can anyone help please.
Im writing a small Android game where the player is able to select a "barrier" and drag it accross the screen with their finger. I have the barriers drawn on the screen and I am able to drag it accross the screen.
My problem however is when I add more than 1 barrier, eg 3 barriers, and drag a barrier accross the screen, they all drag and they all drag to the same position. That is to say they all lie on top of each other, making it look as though there is only 1 barrier.
Here is my code, can anyone please tell me where I am going wrong/explain where I am going wrong.
public class MainGamePanel extends SurfaceView implements SurfaceHolder.Callback, SensorEventListener {
// Initialising the Barrier
private Barrier barrier[] = new Barrier[3];
// The Main Game Panel
public MainGamePanel(Context context) {
super(context);
// Adding a call-back (this) to the surfaceHolder to intercept events
getHolder().addCallback(this);
// Creating the Game items
// The starting coordinates of the Barrier
int x = 30;
int y = 270;
barrier[0] = new Barrier(BitmapFactory.decodeResource(getResources(), R.drawable.blue_barrier), x, y);
barrier[1] = new Barrier(BitmapFactory.decodeResource(getResources(), R.drawable.green_barrier), x + 15, y);
barrier[2] = new Barrier(BitmapFactory.decodeResource(getResources(), R.drawable.pink_barrier), x + 30, y);
// Create the Game Loop Thread
thread = new MainThread(getHolder(), this);
// Make the GamePanel focusable so it can handle events
setFocusable(true);
}
// Handles the touch events
public boolean onTouchEvent(MotionEvent event)
{
int eventAction = event.getAction();
int x = (int)event.getX();
int y = (int)event.getY();
switch (eventAction)
{
// Touch down so check if finger is on Barrier
case MotionEvent.ACTION_DOWN:
if (x > barrier[0].getX() && x < barrier[0].getX() + 8
&& y > barrier[0].getX() && y < barrier[0].getY() + 8)
{
barrier[0].isTouched();
}
else if (x > barrier[1].getX() && x < barrier[1].getX() + 8
&& y > barrier[1].getX() && y < barrier[1].getY() + 8)
{
barrier[1].isTouched();
}
else if (x > barrier[2].getX() && x < barrier[2].getX() + 8
&& y > barrier[2].getX() && y < barrier[2].getY() + 8)
{
barrier[2].isTouched();
}
break;
// Touch-drag with the Barrier
case MotionEvent.ACTION_MOVE:
// Move the Barrier the same as the finger
for (int i = 0; i < barrier.length; i++)
{
if (barrier[i] == barrier[0])
{
barrier[0].setX(x);
barrier[0].setY(y);
} // end if
else if (barrier[i] == barrier[1])
{
barrier[1].setX(x);
barrier[1].setY(y);
}
else if (barrier[i] == barrier[2])
{
barrier[2].setX(x);
barrier[2].setY(y);
} // end else if
} // end for
break;
case MotionEvent.ACTION_UP:
// Finger no longer on Barrier - Do Nothing
break;
}
return true;
}
// Render - Draws the Game Item Bitmaps to the screen
public void render(Canvas canvas)
{
// Set the background to white
canvas.drawColor(Color.WHITE);
barrier[0].draw(canvas);
barrier[1].draw(canvas);
barrier[2].draw(canvas);
}
// Update
// This is the Game's update method
// It iterates through all the Objects and calls their update() methods (if they have one)
public void update()
{
} // end update
In your barrier move code, you aren't checking a particular barrier is touched, so you're moving all of them to the same coordinates. The following loop does exactly the same thing as your current code:
// Move the Barrier the same as the finger
for (int i = 0; i < barrier.length; i++)
{
barrier[i].setX(x);
barrier[i].setY(y);
} //end for
To fix this, you need to check if the current barrier in the loop is the one that was touched, and can change that whole loop to something like:
// Move the Barrier the same as the finger
for (int i = 0; i < barrier.length; i++)
{
if (barrier[i].isTouched())
{
barrier[i].setX(x);
barrier[i].setY(y);
} // end if
} // end for
You would then need to make sure that you un-set the touched property in the ACTION_UP section. If you post your Barrier class definition I can probably help more.
I'm pretty sure your problem could be solved by making the barriers three separate objects instead of in an array.
As already pointed out, your code in handling the move is wrong because it moves all the Barriers to the same X,Y when it should only move the one that is touched.
Also, you are never resetting the isTouched on the objects in the Action up. When the user lifts their finger you should set them all to isTouched == false. If you don't do that then once you touch one it will always move to the X,Y.

Android - How do I get raw touch screen information?

I'm working on a painting application for Android and I'd like to use raw data from the device's touch screen to adjust the user's paint brush as they draw. I've seen other apps for Android (iSteam, for example) where the size of the brush is based on the size of your fingerprint on the screen. As far as painting apps go, that would be a huge feature.
Is there a way to get this data? I've googled for quite a while, but I haven't found any source demonstrating it. I know it's possible, because Dolphin Browser adds multi-touch support to the Hero without any changes beneath the application level. You must be able to get a 2D matrix of raw data or something...
I'd really appreciate any help I can get!
There are some properties in the Motion Event class. You can use the getSize() method to find the size of the object. The Motion Event class also gives access to pressure, coordinates etc...
If you check the APIDemos in the SDK there's a simple paitning app called TouchPaint
package com.example.android.apis.graphics;
It uses the following to draw on the canvas
#Override public boolean onTouchEvent(MotionEvent event) {
int action = event.getAction();
mCurDown = action == MotionEvent.ACTION_DOWN
|| action == MotionEvent.ACTION_MOVE;
int N = event.getHistorySize();
for (int i=0; i<N; i++) {
//Log.i("TouchPaint", "Intermediate pointer #" + i);
drawPoint(event.getHistoricalX(i), event.getHistoricalY(i),
event.getHistoricalPressure(i),
event.getHistoricalSize(i));
}
drawPoint(event.getX(), event.getY(), event.getPressure(),
event.getSize());
return true;
}
private void drawPoint(float x, float y, float pressure, float size) {
//Log.i("TouchPaint", "Drawing: " + x + "x" + y + " p="
// + pressure + " s=" + size);
mCurX = (int)x;
mCurY = (int)y;
mCurPressure = pressure;
mCurSize = size;
mCurWidth = (int)(mCurSize*(getWidth()/3));
if (mCurWidth < 1) mCurWidth = 1;
if (mCurDown && mBitmap != null) {
int pressureLevel = (int)(mCurPressure*255);
mPaint.setARGB(pressureLevel, 255, 255, 255);
mCanvas.drawCircle(mCurX, mCurY, mCurWidth, mPaint);
mRect.set(mCurX-mCurWidth-2, mCurY-mCurWidth-2,
mCurX+mCurWidth+2, mCurY+mCurWidth+2);
invalidate(mRect);
}
mFadeSteps = 0;
}
Hope that helps :)
I'm working on something similar, and I'd suggest looking at the Canvas and Paint classes as well. Looking at getHistorySize() in Motion Event might also be helpful for figuring out how long a particular stroke has been in play.

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