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Android - Displaying ExoPlayer in a circle

I am trying to display a ExoPlayerView inside a circle, overlaying another ExoPlayer (picture in picture):
I have tried putting the 2nd player inside a frame with rounded corners (both this answer and this one) but the player will always escape the parent frame and draw the video's full rectangle.
I found this solution which uses a GLSurfaceView, however this solution uses the classic MediaPlayer and not ExoPlayer.

For the one that's supposed to have rounded corners, you can set in the layout XML file this about it:
app:surface_type="texture_view"
Found this solution here.
The drawback of using this is mainly performance and battery usage (written here) :
Should I use SurfaceView or TextureView? SurfaceView has a number of
benefits over TextureView for video playback:
Significantly lower power consumption on many devices. More accurate
frame timing, resulting in smoother video playback. Support for secure
output when playing DRM protected content. SurfaceView should
therefore be preferred over TextureView where possible. TextureView
should be used only if SurfaceView does not meet your needs. One
example is where smooth animations or scrolling of the video surface
is required prior to Android N (see How do I get smooth
animation/scrolling of video?). For this case, it’s preferable to use
TextureView only when SDK_INT is less than 24 (Android N) and
SurfaceView otherwise.

You need to create a custom container for it. try this and put you player view in it.
public class RoundFrameLayout extends FrameLayout {
private final Path clip = new Path();
private int posX;
private int posY;
private int radius;
public RoundFrameLayout(Context context) {
this(context,null);
}
public RoundFrameLayout(Context context, AttributeSet attrs) {
this(context, attrs,0);
}
public RoundFrameLayout(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
// We can use outlines on 21 and up for anti-aliased clipping.
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
setClipToOutline(true);
}
}
#Override
protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
posX = Math.round((float) width / 2);
posY = Math.round((float) height / 2);
// noinspection NumericCastThatLosesPrecision
radius = (int) Math.floor((float) Math.min(width, height) / 2);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
setOutlineProvider(new OutlineProvider(posX, posY, radius));
} else {
clip.reset();
clip.addCircle(posX, posY, radius, Direction.CW);
}
}
#Override
protected void dispatchDraw(Canvas canvas) {
// Not needed on 21 and up since we're clipping to the outline instead.
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
canvas.clipPath(clip);
}
super.dispatchDraw(canvas);
}
#Override
public boolean onInterceptTouchEvent(MotionEvent event) {
// Don't pass touch events that occur outside of our clip to the children.
float distanceX = Math.abs(event.getX() - posX);
float distanceY = Math.abs(event.getY() - posY);
double distance = Math.hypot(distanceX, distanceY);
return distance > radius;
}
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
static class OutlineProvider extends ViewOutlineProvider {
final int left;
final int top;
final int right;
final int bottom;
OutlineProvider(int posX, int posY, int radius) {
left = posX - radius;
top = posY - radius;
right = posX + radius;
bottom = posY + radius;
}
#Override
public void getOutline(View view, Outline outline) {
outline.setOval(left, top, right, bottom);
}
}
}

Moving and rotating a triangle simultaneously around a circle: Android [closed]

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I have a triangle image whose one edge is always in the same direction as the circle.
This image has to be moved around the circle based on user swipe/drag. So, it has to both rotate (so that it's edge is in same direction as the circle) and at the same time revolve around the circle.
How to implement this feature?
UPDATE: My custom View is as follows:
public class ThermoView extends FrameLayout{
private ImageView mThermoBgrd;
private ImageView mCurTempArrow;
public static final int THEMROSTAT_BACKGROUND = 0;
public static final int THEMROSTAT_CURR_TEMP = 1;
public ThermostatView(Context context, AttributeSet attrs) {
super(context, attrs);
mThermoBgrd = new ImageView(context);
mThermoBgrd.setImageResource(R.drawable.circle_icon);
addView(mThermoBgrd, ThermostatView.THEMROSTAT_BACKGROUND);
mCurTempArrow = new ImageView(context);
mCurTempArrow.setImageResource(R.drawable.ruler_triangle_icon);
mCurTempArrow.setScaleType(ImageView.ScaleType.MATRIX);
addView(mCurTempArrow, ThermostatView.THEMROSTAT_CURR_TEMP, new LayoutParams(50, 50));
}
#Override
protected void onLayout(boolean changed, int left, int top, int right,
int bottom) {
super.onLayout(changed, left, top, right, bottom);
int currTempHeight = mCurTempArrow.getMeasuredHeight();
int currTempWidth = mCurTempArrow.getMeasuredWidth();
int parentWidth = right - left;
int parentHeight = bottom - top;
int padding = currTempHeight;
//We need square container for the circle.
int containerLeft = padding;
int containerTop = parentHeight - parentWidth + padding;
int containerRight = parentWidth - padding;
int containerBottom = parentHeight - padding;
int containerWidth = containerRight - containerLeft;
int containerHeight = containerBottom - containerTop;
//place the arrow indicating current temperature
int curTempLeft = containerRight - ((containerWidth/2) + currTempWidth/2);
int curTempTop = containerTop - (currTempHeight/2);
int curTempRight = curTempLeft + currTempWidth;
int curTempBottom = curTempTop + currTempHeight;
mCurTempArrow.layout(curTempLeft, curTempTop, curTempRight, curTempBottom);
}

try this (it uses Paths instead of Bitmaps but the idea is the same):
public class MyView extends View {
private Paint mPaint;
private Path mTriangle;
private Path mCircle;
private Matrix mMatrix;
private float mAngle;
public MyView(Context context) {
super(context);
mPaint = new Paint();
mPaint.setStrokeWidth(10);
mPaint.setStyle(Style.STROKE);
mTriangle = new Path();
mTriangle.moveTo(0, -21);
mTriangle.lineTo(0, 21);
mTriangle.lineTo(36, 0);
mTriangle.close();
mCircle = new Path();
mCircle.addCircle(0, 0, 50, Direction.CW);
mMatrix = new Matrix();
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float w2 = getWidth() / 2f;
float h2 = getHeight() / 2f;
mAngle = (float) (180 * Math.atan2(event.getY() - h2, event.getX() - w2) / Math.PI);
invalidate();
return true;
}
#Override
protected void onDraw(Canvas canvas) {
float w2 = getWidth() / 2f;
float h2 = getHeight() / 2f;
mMatrix.reset();
mMatrix.postTranslate(w2, h2);
canvas.concat(mMatrix);
mPaint.setColor(0xaaff0000);
canvas.drawPath(mCircle, mPaint);
mMatrix.reset();
mMatrix.postTranslate(60, 0);
mMatrix.postRotate(mAngle);
canvas.concat(mMatrix);
mPaint.setColor(0xaa00ff00);
canvas.drawPath(mTriangle, mPaint);
}
}

Since I don't know if you are using open GL or a standard canevas, I can't really give you some working code. But the general idea is (assuming you have the current position of the triangle (x, y) stored, and the center of your circle (cx, cy) stored.
Do the following:
v = (cx-x, cy-y) // v is the normal vector of your triangle: it faces the center of the circle
triangle.translate(v) // translate to the center of the circle
triangle.rotate(angle) // rotate the triangle on itself
v.rotate(angle) // apply the same rotation on the normal vector
triangle.translate(-v) // translate back on the circle, but since v is rotated, the position will be updated
I hope it is clear enough, good luck
EDIT:
First, you should really try to be more accurate: in your first post, you didn't say that the triangle was an image (that's important). Then you don't say what is your current rendering, what works, what doesn't. I would be easier to help you to know what your program currently display.
From your code, I assume you place the triangle image properly , but it is not rotated. So first, try to add
//place the arrow indicating current temperature
int curTempLeft = containerRight - ((containerWidth/2) + currTempWidth/2);
int curTempTop = containerTop - (currTempHeight/2);
int curTempRight = curTempLeft + currTempWidth;
int curTempBottom = curTempTop + currTempHeight;
mCurTempArrow.setRotate(angle); // rotate the image. angle is in degrees
mCurTempArrow.layout(curTempLeft, curTempTop, curTempRight, curTempBottom);
If you don't know the angle, you might have to compute it from the previous position of the triangle

Android Custom View code stopped working correctly in Jelly Bean 4.2

The code below is a custom view - it draws a circle, adds notches according to a scale and adds the scale text. This was derived from Mind The Robot's excellent tutorial on creating a vintage thermometer. http://mindtherobot.com/blog/272/android-custom-ui-making-a-vintage-thermometer/
This code works fine on devices running up to Jelly Bean 4.1.2 but breaks on 4.2. On 4.2 the numbers no longer get drawn around the circle but seem to be spread all over the screen.The code worked fine on a Nexus 7 until it got the 4.2 update so it can't be a device issue. I have tested it on a Nexus S running 4.1.2 and a Nexus 4 running 4.2 it works fine on the Nexus S but not on the Nexus 4.
Unfortunately as a new user I can't post screenshots, I'll try to describe it: The numbers display correctly for the first half of the dial, the rest of the numbers are scattered across the screen.
I have looked at the 4.2 change log but I can't see anything that would cause this to happen. I have looked for similar issues on-line but these all seem to be to do with hardware acceleration - I have tried various combinations of setting hardware acceleration in the manifest but nothing has any impact.
I'd really appreciate any input on what might be causing this to happen.
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.view.View;
public class AneroidView extends View {
// drawing tools
private RectF rimRect;
private RectF faceRect;
private Paint scalePaint;
private RectF scaleRect;
private Paint backgroundPaint;
// end drawing tools
private Bitmap background; // holds the cached static part
private int totalNotches = 130;
private int incrementPerLargeNotch = 10;
private int incrementPerSmallNotch = 1;
private float degreesPerNotch = 360.0f / totalNotches;
private int scaleCenterValue = 1000; // the one in the top center (12 o'clock)
private int scaleMinValue = 935;
private int scaleMaxValue = 1065;
public AneroidView(Context context) {
super(context);
init(context, null);
}
public AneroidView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs);
}
public AneroidView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs);
}
private void init(Context context, AttributeSet attrs) {
rimRect = new RectF(0.1f, 0.1f, 0.9f, 0.9f);
float rimSize = 0.02f;
faceRect = new RectF();
faceRect.set(rimRect.left + rimSize, rimRect.top + rimSize,
rimRect.right - rimSize, rimRect.bottom - rimSize);
scalePaint = new Paint();
scalePaint.setStyle(Paint.Style.STROKE);
scalePaint.setColor(Color.rgb(49, 79, 79));
scalePaint.setStrokeWidth(0.005f);
scalePaint.setAntiAlias(true);
scalePaint.setTextSize(0.045f);
scalePaint.setTypeface(Typeface.SANS_SERIF);
scalePaint.setTextScaleX(0.8f);
scalePaint.setTextAlign(Paint.Align.CENTER);
// The scale rectangular is located .10 from the outer rim.
float scalePosition = 0.10f;
scaleRect = new RectF();
scaleRect.set(faceRect.left + scalePosition, faceRect.top + scalePosition,
faceRect.right - scalePosition, faceRect.bottom - scalePosition);
}
private void drawScale(Canvas canvas) {
// Draw a large notch every large increment, and a small
// notch every small increment.
canvas.drawOval(scaleRect, scalePaint);
canvas.save(Canvas.MATRIX_SAVE_FLAG);
for (int i = 0; i < totalNotches; ++i) {
float y1 = scaleRect.top;
float y2 = y1 - 0.015f;
float y3 = y1 - 0.025f;
int value = notchToValue(i);
if (i % (incrementPerLargeNotch/incrementPerSmallNotch) == 0) {
if (value >= scaleMinValue && value <= scaleMaxValue) {
// draw a nick
canvas.drawLine(0.5f, y1, 0.5f, y3, scalePaint);
String valueString = Integer.toString(value);
// Draw the text 0.15 away from y3 which is the long nick.
canvas.drawText(valueString, 0.5f, y3 - 0.015f, scalePaint);
}
}
else{
if (value >= scaleMinValue && value <= scaleMaxValue) {
// draw a nick
canvas.drawLine(0.5f, y1, 0.5f, y2, scalePaint);
}
}
canvas.rotate(degreesPerNotch, 0.5f, 0.5f);
}
canvas.restore();
}
private int notchToValue(int value) {
int rawValue = ((value < totalNotches / 2) ? value : (value - totalNotches)) * incrementPerSmallNotch;
int shiftedValue = rawValue + scaleCenterValue;
return shiftedValue;
}
private void drawBackground(Canvas canvas) {
if (background != null)
canvas.drawBitmap(background, 0, 0, backgroundPaint);
}
#Override
protected void onDraw(Canvas canvas) {
drawBackground(canvas);
float scale = (float) getWidth();
canvas.save(Canvas.MATRIX_SAVE_FLAG);
canvas.scale(scale, scale);
canvas.restore();
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
regenerateBackground();
}
private void regenerateBackground() {
// free the old bitmap
if (background != null) {
background.recycle();
}
background = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
Canvas backgroundCanvas = new Canvas(background);
float scale = (float) getWidth();
backgroundCanvas.scale(scale, scale);
drawScale(backgroundCanvas);
}
}

Add scalePaint.setLinearText(true);
It will work better but text spacing may look bad.
See the threads below:
Android 4.2 on Nexus 7: canvas.drawText() not working correctly
Android 4.2.1 wrong character kerning (spacing)

I managed to work around the problem by using scalePaint.setLinearText(true) to get around drawing the text characters in one place, setting textSize > 1.0f to get around the kerning problem, and then using canvas.scale(float, float) to get the font to the right size. It is ugly and a pain, but it works for me.

Here's another work around for the kerning issue. drawTextOnPath works so...
Replace this:
//canvas.drawText("Smushed text.", 0.5f, 0.7F, myTextPaint);
with this:
private Path strightPath; <br>
strightPath = new Path(); <br>
strightPath.moveTo(0.1f, 0.5f);<br>
strightPath.lineTo(0.9f, 0.5f); <br>
canvas.drawTextOnPath("This text is not smushed together.", strightPath, 0.0f, 0.2f, myTextPaint);

ImageView adjustViewBounds not working

I have an ImageView with android:layout_width=100dp, android:layout_height=wrap_content and android:adjustViewBounds=true
It's source is a 50 x 50 px picture. But the aspect ratio is not preserved - height of the ImageView is 50px, not 100px (i.e. adjustViewBounds is not working). If I have a 200x200px picture it works - width and height are 100px. This code results in a 100px wide and 50px tall picture but the src image is square:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ImageView
android:id="#+id/photo"
android:src="#drawable/icon"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:scaleType="fitXY"
android:adjustViewBounds="true" />
</LinearLayout>

The issue is that adjustViewBounds will not increase the size of the ImageView beyond the natural dimensions of the drawable. It will only shrink the view to maintain aspect ratio; if you provide a 500x500 image instead of a 50x50 image, this should work.
If you're interested in the spot where this behavior is implemented, see ImageView.java's onMeasure implementation.
One workaround is to implement a custom ImageView that changes this behavior in onMeasure.

There's a more simple way. Make your ImageView like this:
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="fitCenter"
android:adjustViewBounds="true"/>
This way drawable will stretch to fit in the ImageView center by preserving
the aspect ratio. We just have to calculate the right height to make it proportional
so we don't have any blank space:
private void setImageBitmap(Bitmap bitmap, ImageView imageView){
float i = ((float)imageWidth)/((float)bitmap.getWidth());
float imageHeight = i * (bitmap.getHeight());
imageView.setLayoutParams(new RelativeLayout.LayoutParams(imageWidth, (int) imageHeight));
imageView.setImageBitmap(bitmap);
}

In addition to #RomanNurik's answer
You can find working solution here, either copy-paste code or just add the Gradle dependency
dependencies {
compile 'com.inthecheesefactory.thecheeselibrary:adjustable-imageview:1.0.1'
}
P.S. Solution provided by #Nilzor didn't work for me

I had a similar requirement; in my case, I wanted the image to be square, and wanted the ImageView to match the aspect ratio so I could use its background and padding to draw a border.
I read the answers here but instead of overriding ImageView, I decided to make a Layout that guarantees its contents (should be only one view) are square. That way I could use a standard ImageView inside it. (And you never know, I might want to make something else square later. Although probably not.)
In case it's useful for anyone else, here's the code (feel free to copy). There are probably bugs as I just made it work for my app then stopped. :)
public class SquareLayout extends ViewGroup
{
public SquareLayout(Context context, AttributeSet attrs, int defStyle)
{
super(context, attrs, defStyle);
}
public SquareLayout(Context context, AttributeSet attrs)
{
super(context, attrs);
}
public SquareLayout(Context context)
{
super(context);
}
#Override
protected void onLayout(boolean changed, int l, int t, int r, int b)
{
// Work out width and height, and square size.
int width = r - l;
int height = b - t;
int size, xOffset, yOffset;
if(width < height)
{
size = width;
xOffset = 0;
yOffset = (height - size) / 2;
}
else
{
size = height;
xOffset = (width - size) / 2;
yOffset = 0;
}
for(int i = 0; i < getChildCount(); i++)
{
View child = getChildAt(i);
child.layout(xOffset, yOffset, size + xOffset, size + yOffset);
}
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
// Get width and height.
int w = -1, h = -1;
switch(MeasureSpec.getMode(widthMeasureSpec))
{
case MeasureSpec.AT_MOST:
case MeasureSpec.EXACTLY:
w = MeasureSpec.getSize(widthMeasureSpec);
break;
case MeasureSpec.UNSPECIFIED:
break;
}
switch(MeasureSpec.getMode(heightMeasureSpec))
{
case MeasureSpec.AT_MOST:
case MeasureSpec.EXACTLY:
h = MeasureSpec.getSize(heightMeasureSpec);
break;
case MeasureSpec.UNSPECIFIED:
break;
}
// If only one of width/height is unspecified, set them both the same.
if(w == -1 && h != -1)
{
w = h;
}
else if(h == -1 && w != -1)
{
h = w;
}
// Either they're both specified or both unspecified.
int childMeasureSpec;
if(w == -1)
{
childMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
}
else
{
childMeasureSpec = MeasureSpec.makeMeasureSpec(w, MeasureSpec.EXACTLY);
}
// Pass through to children.
int maxDimension = 1;
for(int i = 0; i < getChildCount(); i++)
{
View child = getChildAt(i);
child.measure(childMeasureSpec, childMeasureSpec);
maxDimension = Math.max(maxDimension, child.getMeasuredWidth());
maxDimension = Math.max(maxDimension, child.getMeasuredHeight());
}
if(w == -1)
{
w = maxDimension;
h = maxDimension;
}
setMeasuredDimension(w, h);
}
}

this line will do it for you android:scaleType="fitXY"

Animate a Drawable in a custom view

I'm trying to animate a ShapeDrawable in a custom view. But I am not sure what the best method is to accomplish this task.
Should I try and draw a pawn on a path and call invalidate() until it has reached the destination square? Or is there some better method using maybe an AsyncTask or Handler?
Here is my code, I have omitted a lot of methods and variables in order to make it readable.
public class CheckerBoard extends View {
public enum State implements Parcelable {
EMPTY(0), WHITE(1), BLACK(2);
}
private final State[][] boardStates = new State[SIZE][SIZE];
#Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(bgColor);
for (int y = 0; y < SIZE; y++) {
for (int x = 0; x < SIZE; x++) {
if ((y % 2 == 0 && x % 2 != 0) || (y % 2 != 0 && x % 2 == 0)) {
drawRect(x, y, canvas);
drawPawn(x, y, canvas);
}
}
}
}
private void drawRect(int x, int y, Canvas c) {
}
private void drawPawn(int x, int y, Canvas c) {
}
private void init() {
setupBoard();
pawnLinePaint.setStyle(Paint.Style.STROKE);
wPawnDrawable.getPaint().setColor(wColor);
wPawnDrawable.getPaint().setShadowLayer(tileSize + 2, 4, 4, Color.GRAY);
bPawnDrawable.getPaint().setColor(bColor);
bPawnDrawable.getPaint().setShadowLayer(tileSize + 2, 4, 4, Color.GRAY);
playerState = startState;
}
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
int x = (int) (event.getX() / tileSize);
int y = (int) (event.getY() / tileSize);
if (selection[0] >= 0) { // A tile is already selected
if (isValidMove(selection[0], selection[1], x, y)) {
makeMove(x, y);
clearSelection();
switchPlayer();
invalidate();
}
} else { // New selection
if (isValidSelection(x, y)) {
selection[0] = x;
selection[1] = y;
invalidate();
}
}
return true;
default:
return super.onTouchEvent(event);
}
}
private void makeMove(int x, int y) {
// Move the pawn to the new square
boardStates[y][x] = boardStates[selection[1]][selection[0]];
// Old square is now empty
boardStates[selection[1]][selection[0]] = State.EMPTY;
}
private void switchPlayer() {
playerState = playerState == State.WHITE ? State.BLACK : State.WHITE;
}
public CheckerBoard(Context context) {
super(context);
init();
}
public CheckerBoard(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public CheckerBoard(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private class Pawn extends ShapeDrawable {
public Pawn() {
super(new OvalShape());
}
public void drawWithCircles(Canvas canvas, float x, float y){
super.draw(canvas);
canvas.drawCircle(x * tileSize + pawnDiameter, y * tileSize + pawnDiameter, pawnDiameter - pawnPadding,
pawnLinePaint);
canvas.drawCircle(x * tileSize + pawnDiameter, y * tileSize + pawnDiameter, pawnDiameter - pawnPadding * 6,
pawnLinePaint);
canvas.drawCircle(x * tileSize + pawnDiameter, y * tileSize + pawnDiameter, pawnDiameter - pawnPadding * 8,
pawnLinePaint);
}
}
}
Thank you for your help.
Blight

You should create two threads for your application. One thread is the UI thread that only draws the board in its current state. The other thread is the Game engine or animation thread that moves the items on the board.
The first thread runs at whatever your desired frame rate is and the 2nd thread should run considerably faster. This way you don't actually have to handle the animation yourself as the UI thread just draws the board as it currently is. In your engine thread you update the state of the game,board,chess pieces, every cycle of the thread.
Doing things this way has a couple of benefits. First your game's framerate won't drop if the Engine thread gets bogged down in some sort of computation. Second it allows you to abstract the drawing away from the game in a way that will make debugging much easier.
Take a progress bar for example. Let say you tried to create a file uploader with a progress bar but only had one thread. So you start the progress bar then start uploading the file. If the upload process is blocking then you have to wait for the file to finish uploading before you can update the progress bar, essentially rendering the progress bar useless. But if you did this with two threads then you could set it up so one thread simply updates the progress bars graphics based upon some common variable. The other tread is responsible for performing an action and updating the progress variable.
Check out these links for more info:
http://obviam.net/index.php/the-android-game-loop/
http://www.rbgrn.net/content/54-getting-started-android-game-development
http://www.helloandroid.com/tutorials/using-threads-and-progressdialog