I've been working on the example from http://obviam.net/index.php/a-very-basic-the-game-loop-for-android/ In this I want to make few changes.
Speed.java
public class Speed {
public static final int DIRECTION_RIGHT = 1;
public static final int DIRECTION_LEFT = -1;
public static final int DIRECTION_UP = -1;
public static final int DIRECTION_DOWN = 1;
private float xv = 1; // velocity value on the X axis
private float yv = 1; // velocity value on the Y axis
private int xDirection = DIRECTION_RIGHT;
private int yDirection = DIRECTION_DOWN;
public Speed() {
this.xv = 1;
this.yv = 1;
}
public Speed(float xv, float yv) {
this.xv = xv;
this.yv = yv;
}
public float getXv() {
return xv;
}
public void setXv(float xv) {
this.xv = xv;
}
public float getYv() {
return yv;
}
public void setYv(float yv) {
this.yv = yv;
}
public int getxDirection() {
return xDirection;
}
public void setxDirection(int xDirection) {
this.xDirection = xDirection;
}
public int getyDirection() {
return yDirection;
}
public void setyDirection(int yDirection) {
this.yDirection = yDirection;
}
// changes the direction on the X axis
public void toggleXDirection() {
xDirection = xDirection * -1;
}
// changes the direction on the Y axis
public void toggleYDirection() {
yDirection = yDirection * -1;
}
}
Using this, the image moves in all directions. Now I just want to limit this movement from bottom to top. And the functionality for onclick is that, we can click and drag the image to required position. I want to replace that with just make the image to disappear or go to another activity. Please help me in making changes to this code. Thanks in advance.
if you have used SurfaceView then in onDraw(Canvas canvas) method the code is for moving image from bottom to top is something like this.
canvas.drawBitmap(bitmap,xPoint,yPoint,paint);
where bitmap is an image(Bitmap which you want to move),xPoint is the x coordinate,yPoint is the y coordinate and paint is a Paint which is also can be null.
and for bottom to top movement just update
yPoint = yPoint - 1;
in any thread before onDraw() call.
May this help you.
Related
Hi i am developing a snake game and i want to store the snake movement points in a priority queue but i am not getting how to iterate through that priority queue
below is my Priority Queue class and Point class to store points
Priority Queue class:
public class PriorityQueue {
private Points[] heap;
private int heapSize,capacity;
/** Constructor **/
public PriorityQueue(){
heapSize = 0;
}
public void setCapacity( int capacity)
{
this.capacity = capacity + 1;
heap = new Points[this.capacity];
}
/** function to clear **/
public void clear()
{
heap = new Points[capacity];
heapSize = 0;
}
/** function to check if empty **/
public boolean isEmpty()
{
return heapSize == 0;
}
/** function to check if full **/
public boolean isFull()
{
return heapSize == capacity - 1;
}
/** function to get Size **/
public int size()
{
return heapSize;
}
// method to insert point
public void insert(float x, float y, float rotation, int priority)
{
Points points = new Points(x,y,rotation,priority);
heap [++heapSize] = points;
int pos = heapSize;
while (pos != 1 && points.priority > heap[pos/2].priority)
{
heap[pos] = heap[pos/2];
pos /=2;
}
heap[pos] = points;
}
// function to remove point
public Points remove()
{
int parent, child;
Points item, temp;
if (isEmpty() )
{
System.out.println("Heap is empty");
return null;
}
item = heap[1];
temp = heap[heapSize--];
parent = 1;
child = 2;
while (child <= heapSize)
{
if (child < heapSize && heap[child].priority < heap[child + 1].priority)
child++;
if (temp.priority >= heap[child].priority)
break;
heap[parent] = heap[child];
parent = child;
child *= 2;
}
heap[parent] = temp;
return item;
}
}
Point Class:
public class Points {
private float X;
private float Y;
int priority;
private float rotation;
public Points(float x, float y,float rotation,int priority)
{
this.X = x;
this.Y = y;
this.rotation = rotation;
this.priority = priority;
}
public float getX() {
return X;
}
public float getY() {
return Y;
}
public float getRotation() {
return rotation;
}
public int getPriority() {
return priority;
}
}
please guide me to how iterate through this Queue Class.
Thank you in advance
I need to make a credits screen (Activity) in my game. It would be just a vertically scrolling text lines without any images. Scrolling is to be performed automatically and no user interaction is allowed. Just like movie credits that goes from bottom to top. After the last text line has disappeared above top of the screen, it should restart.
How do I do it? It is sufficient to just use TextView and animate it somehow? Or should I put that TextView into ScrollView? What would you suggest?
I am using this :-
/**
* A TextView that scrolls it contents across the screen, in a similar fashion as movie credits roll
* across the theater screen.
*
* #author Matthias Kaeppler
*/
public class ScrollingTextView extends TextView implements Runnable {
private static final float DEFAULT_SPEED = 15.0f;
private Scroller scroller;
private float speed = DEFAULT_SPEED;
private boolean continuousScrolling = true;
public ScrollingTextView(Context context) {
super(context);
setup(context);
}
public ScrollingTextView(Context context, AttributeSet attributes) {
super(context, attributes);
setup(context);
}
private void setup(Context context) {
scroller = new Scroller(context, new LinearInterpolator());
setScroller(scroller);
}
#Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
if (scroller.isFinished()) {
scroll();
}
}
private void scroll() {
int viewHeight = getHeight();
int visibleHeight = viewHeight - getPaddingBottom() - getPaddingTop();
int lineHeight = getLineHeight();
int offset = -1 * visibleHeight;
int totallineHeight = getLineCount() * lineHeight;
int distance = totallineHeight + visibleHeight;
int duration = (int) (distance * speed);
if (totallineHeight > visibleHeight) {
scroller.startScroll(0, offset, 0, distance, duration);
if (continuousScrolling) {
post(this);
}
}
}
#Override
public void run() {
if (scroller.isFinished()) {
scroll();
} else {
post(this);
}
}
public void setSpeed(float speed) {
this.speed = speed;
}
public float getSpeed() {
return speed;
}
public void setContinuousScrolling(boolean continuousScrolling) {
this.continuousScrolling = continuousScrolling;
}
public boolean isContinuousScrolling() {
return continuousScrolling;
}
}
i am using andengine for implementing accelerometer sensor in android. my requirement is i have to move the ball to the center of the screen using accelerometer. I am able to achieve that when the device is in lying flat position. because it uses the X and Y acceleration values for the calculation in AndEngine library.
but the problem arise when i hold the device in straight up position. the object doesn't move to the center and it always lays down to the bottom bar of the screen. however, i tried to calculate the z value at this time and inject my logic into AccelerationData class to use z value instead of y. but no success. please go through the following code and guide me what wrong i am doing.
AccelerationData.java
public class AccelerationData extends BaseSensorData {
// ===========================================================
// Constants
// ===========================================================
private static final IAxisSwap AXISSWAPS[] = new IAxisSwap[4];
static {
AXISSWAPS[Surface.ROTATION_0] = new IAxisSwap() {
#Override
public void swapAxis(final float[] pValues) {
final float x = -pValues[SensorManager.DATA_X];
final float y;
if(SensorManager.DATA_Z > -0.50 && SensorManager.DATA_Z <0.50){
y = pValues[SensorManager.DATA_Z];
}else{
y = pValues[SensorManager.DATA_Y];
}
pValues[SensorManager.DATA_X] = x;
pValues[SensorManager.DATA_Y] = y;
}
};
AXISSWAPS[Surface.ROTATION_90] = new IAxisSwap() {
#Override
public void swapAxis(final float[] pValues) {
final float x = pValues[SensorManager.DATA_Y];
final float y = pValues[SensorManager.DATA_X];
pValues[SensorManager.DATA_X] = x;
pValues[SensorManager.DATA_Y] = y;
}
};
AXISSWAPS[Surface.ROTATION_180] = new IAxisSwap() {
#Override
public void swapAxis(final float[] pValues) {
final float x = pValues[SensorManager.DATA_X];
final float y = -pValues[SensorManager.DATA_Y];
pValues[SensorManager.DATA_X] = x;
pValues[SensorManager.DATA_Y] = y;
}
};
AXISSWAPS[Surface.ROTATION_270] = new IAxisSwap() {
#Override
public void swapAxis(final float[] pValues) {
final float x = -pValues[SensorManager.DATA_Y];
final float y = -pValues[SensorManager.DATA_X];
pValues[SensorManager.DATA_X] = x;
pValues[SensorManager.DATA_Y] = y;
}
};
}
...
...
}
here i am showing the usage of z value only when device is at 0 degree. any help would be greatly appreciated.
I want one of my ViewGroup to be movable. Let's say, I want to click on it and the content below it reveals. On second click it closes again. Kind of sliding menu behaviour.
Here are my classes:
Custom scroller:
public class MyScroller implements Runnable {
private static final String TAG = "MY_SCROLLER";
private static final int ANIMATION_DURATION = 500;
private final Scroller mScroller;
private View mScrollingView;
private int lastX = 0;
private static final Interpolator sInterpolator = new Interpolator() {
public float getInterpolation(float t) {
t -= 1.0f;
return t * t * t * t * t + 1.0f;
}
};
MyScroller(final View view) {
mScroller = new android.widget.Scroller(view.getContext(), sInterpolator);
mScrollingView = view;
}
public void start(int initialVelocity) {
Log.d(TAG, "start() called");
int initialX = mScrollingView.getScrollX();
int maxX = mScrollingView.getWidth();
mScroller.startScroll(0, 0, maxX, 0, ANIMATION_DURATION);
lastX = initialX;
mScrollingView.post(this);
}
public void run() {
Log.d(TAG, "run() called");
if (mScroller.isFinished()) {
mScrollingView.invalidate();
return;
}
boolean more = mScroller.computeScrollOffset();
int x = mScroller.getCurrX();
int diff = x - lastX;
if (diff != 0) {
Log.d(TAG, "x = " + x);
mScrollingView.offsetLeftAndRight(diff);
mScrollingView.invalidate();
lastX = x;
} else {
forceFinished();
}
if (more) {
mScrollingView.postDelayed(this, 16);
}
}
void forceFinished() {
if (!mScroller.isFinished()) {
mScroller.forceFinished(true);
mScrollingView.invalidate();
}
}
}
and usage:
viewGroup.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
new MyScroller(v).start(0);
}
});
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
new MyScroller(v).start(0);
}
});
For Button everything works fine - it smoothly moves.
But ViewGroups that I tried leave a trail like on screenshot.
RelativeLayout with Button inside left a trail.
Standalone Button moved perfectly.
What am I missing here?
I am using a View extended from View group and the onDraw is not getting called when I call invalidate.Can any one please explain?
The code is given below
public class BarGraph extends View {
private int viewHeight;
private int viewWidth; // height and width of bar graph dynamically calculated.
private int mGraphColor; // the colour of the bar graph.
private ArrayList<Integer> mTodays; // The array list that handles the input to draw the graph.
private final int barCount = 20; // Number of bars in the bar graph...here set as 20.
/*
* The maximum action value a bar can take.
* This is calculated based on the action array
* passed to the chart.
*/
private int yMax = 0;
private Paint graphColor;
public BarGraph(Context context, int graphColor) {
super(context);
this.setWillNotDraw(false);
mGraphColor = graphColor;
setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
initializePaintObjects();
}
public BarGraph(Context context, AttributeSet attrs) {
super(context, attrs);
this.setWillNotDraw(false);
initializePaintObjects();
}
private void initializePaintObjects(){
graphColor = new Paint();
graphColor.setColor(mGraphColor);
graphColor.setStyle(Style.FILL);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if(mTodays == null) // If the array list is empty.
return;
if(yMax <= 0)
return;
int left = 0;
viewHeight = getHeight();
viewWidth = getWidth();
if((viewWidth % barCount) > 0){ //adjusting the view width so that bars correctly fits in
int newWidth = (int) (Math.floor(viewWidth / barCount) * barCount);
left = (int) Math.floor(((viewWidth - newWidth)/2));
viewWidth = (int) Math.floor((viewWidth / barCount) * barCount);
}
int columnWidth = 2;
columnWidth = (int) Math.floor(viewWidth / barCount);
int xFactor = 1;
xFactor = (int) Math.ceil(columnWidth * 0.33);
int barWidth = 1;
barWidth = columnWidth - xFactor;
graphColor.setStrokeWidth(barWidth);
int j = 0;
for(int i = 0; i < mTodays.size() ; i++){
int todayValue = mTodays.get(i);
float todaysHeight;
if(todayValue == 0){
todaysHeight = (float) (viewHeight-viewHeight*(.001));
}else{
todaysHeight = getYValue(todayValue);
}
canvas.drawLine(((j*columnWidth)+xFactor + left) , viewHeight, ((j*columnWidth)+xFactor + left), todaysHeight, graphColor);
j++;
}
}
public void setData(ArrayList<Integer>todays){
mTodays = todays;
yMax = 0;
for (int val : mTodays){
yMax = yMax > val ? yMax : val;
}
invalidate();
}
private int getYValue(int item){
int percent = (item * 100)/yMax;
return (viewHeight) - ((percent * viewHeight)/100);
}
}
Thanks for all your attempts.The problem was actually in the Main Activity.
The following is the correct code
final Handler handler = new Handler();
Timer timer2 = new Timer();
TimerTask testing = new TimerTask() {
public void run() {
handler.post(new Runnable() {
public void run() {
for(int j=0;j<19;j++){
todays.set(j, todays.get(j+1));
}
Random diceRoller = new Random();
todays.set(19, diceRoller.nextInt(100)*10+1);
MainActivity.this.runOnUiThread(new Runnable() {
#Override
public void run() {
// TODO Auto-generated method stub
bargraph.setData(todays);
}
});
}
});
I had not written the runOnUiThread at first...My bad...