Develop Reference

Android: How to make a gridview of equal proportions within the Java code

I am working on an application which has a main screen with a gridview layout.
As it stands currently, I am hardcoding in DP numbers for the height and width of the boxes, which I obviously do not want to do. How to I create code that will determine the users' screen size and match the boxes accordingly so that someone with a large phone like a note will view the same thing as someone on a droid mini? IE, when hardcoding to 500dp on each side, it looks like this:
But my goal is to make it look like this on every screen size:
Currently, this is the Java code I have:
public class ActivityAdapter extends BaseAdapter {
//Array of Icons that will be used as menu choices
public static int[] imageOptions = {
R.drawable.vacation_quota, //Position 0
R.drawable.revenue_deficit, //Position 1
//+ many more options...
};
private Context context;
//Constructor to pass context back to Main class
public ActivityAdapter(Context applicationContext) {
context = applicationContext;
}
//Number of elements to be displayed on the grid
#Override
public int getCount() {
return imageOptions.length;
}
#Override
public View getView(int position, View convertView, ViewGroup arg2) {
ImageView iv;
if(convertView != null){
iv = (ImageView) convertView;
} else {
iv = new ImageView(context);
//Here I have it hard coded to match a 480px width. Here is where I need to change it, just not sure how
iv.setLayoutParams(new GridView.LayoutParams(240, 240));
iv.setScaleType(ScaleType.CENTER_CROP); //Center the cropping
}
//Sets the image to correspond to its position within the array.
iv.setImageResource(imageOptions[position]);
return iv;
}
Any ideas? I think logically I want to figure out the screen dimensions and use them to make the image dimensions match, just not sure how. Research from other threads has not helped a great deal so hoping I can get a simpler answer here with code posting.

You should get the screen width and height. Then use these values to dynamically set height and width for each cell

Try this code-
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle state) {
setContentView(new ViewGroup(this) {
private RelativeLayout[] items = new RelativeLayout[9];
private int width, height, itemWidth, itemHeight;
{
Random r = new Random();
for (int i = 0; i < 9; i++) {
items[i] = new RelativeLayout(getContext());
float[] hsv = new float[] {360 * r.nextFloat(), .50f, .75f};
items[i].setBackgroundColor(Color.HSVToColor(hsv));
addView(items[i]);
// UPDATE ////////////////////////////////////
ImageView image = new ImageView(getContext());
switch (i) {
case 0: // top left
case 1: // top center
case 2: // top right
case 3: // center left
case 4: // center center
case 5: // center right
case 6: // bottom left
case 7: // bottom center
case 8: // bottom right
image.setImageResource(R.drawable.ic_launcher);
break;
}
image.setScaleType(ScaleType.FIT_XY);
image.setLayoutParams(new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.MATCH_PARENT
));
items[i].addView(image);
//////////////////////////////////////////////
}
}
#Override
protected void onMeasure(int wMS, int hMS) {
width = MeasureSpec.getSize(wMS);
height = MeasureSpec.getSize(hMS);
itemWidth = width / 3;
itemHeight = height / 3;
wMS = MeasureSpec.makeMeasureSpec(itemWidth, MeasureSpec.EXACTLY);
hMS = MeasureSpec.makeMeasureSpec(itemHeight, MeasureSpec.EXACTLY);
measureChildren(wMS, hMS);
setMeasuredDimension(width, height);
}
#Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
for (int i = 0; i < 9; i++) {
l = itemWidth * (i % 3);
t = itemHeight * (i / 3);
r = l + itemWidth;
b = t + itemHeight;
items[i].layout(l, t, r, b);
}
}
});
super.onCreate(state);
}
}
Output-
Edit-
For creating scrollable grid view see this http://www.androidhive.info/2012/02/android-gridview-layout-tutorial/

I ended up not able to use some of the recommendations here and had to use a deprecated method to retain my app structure. The code specifically that was added to mine was:
iv = new ImageView(context);
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
float width2 = display.getWidth();
int length = (int) (width2/2);
iv.setLayoutParams(new GridView.LayoutParams(length, length));
With this, the height and width would crop to the right size depending on the size of the screen.

android: setting a button programmatically using setX and setY

public class Game_collecting_view extends View
{
Button image_boy;
private static final int BOY_DIAMETER = 200; // initial spot size
int boy_width =0;
int boy_height =0;
public void setGame_collecting(Game_collecting mGame_collecting)
{
this.mGame_collecting = mGame_collecting;
}
// constructs a new View
public Game_collecting_view(Context context, RelativeLayout parentLayout)
{
super(context);
resources = context.getResources(); // save Resources for loading external values
layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// get references to various GUI components
relativeLayout = parentLayout;
spotHandler = new Handler(); // used to add spots when game starts
}
#Override
protected void onSizeChanged(int width, int height, int oldw, int oldh)
{
viewWidth = width; // save the new width
viewHeight = height; // save the new height
}
public void set_boy()
{
final Button boy = (Button) layoutInflater.inflate(R.layout.untouched, null);
boy.setX(viewWidth /2);
boy.setY(viewHeight - BOY_DIAMETER);
boy.setPadding(0,0,0,0);
boy.setBackgroundResource(R.drawable.blue);
boy.setLayoutParams(new RelativeLayout.LayoutParams(BOY_DIAMETER, BOY_DIAMETER));
relativeLayout.addView(boy); // add spot to the screen
Toast.makeText(getContext(), "set_boy\nviewWidth=" +viewHeight +"\nviewHeight=" +viewHeight, Toast.LENGTH_SHORT).show();
boy.setOnClickListener
(
new OnClickListener()
{
public void onClick(View v)
{
touchedSpot(boy);
}
}
);
}
public void resume(Context context)
{
resetGame();
}
public void resetGame()
{
for (int i = 1; i <= INITIAL_SPOTS; ++i)
{
spotHandler.postDelayed(addSpotRunnable, i * SPOT_DELAY);
generate_text();
}
set_boy();
}
private Runnable addSpotRunnable = new Runnable()
{
public void run()
{
addNewSpot(); // add a new spot to the game
}
};
Objective:
I would like to set the boy icon at the bottom middle of the screen.
The boy icon is set at this way for later dynamic interface (swipe the screen to the right the boy icon will move to the right, vice versa)
Observation:
The toast reports both the viewWidth and viewHeight =0, and the boy icon appears at 0,0 (left upper corner). If I set the setY(viewHeight + BOY_DIAMETER), the boy icon will be located at (0, 200).
Question:
I would like to ask why the viewWidth and viewHeight both report 0. How could the onSizeChanged be called immediately such that the boy icone could be set at the bottom center of the screen?
Thanks!!

The location is null until Android has calculated their positions. You can retrieve the height and width like this:
image_boy.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
int height = image_boy.getHeight();
int width = image_boy.getWidth();
//these values won't be null
}
});

set layout param for setting the view position

Gallery like view with center image zoom

Here I need a gallery like view with only three images to be shown at a time on screen. In this the middle image will be larger than the two other images on its sides.
If the user scrolls the view next images will slide on screen as it does in gallery and at a time only three images will be shown out of which the center image should automatically zoom when it is shown on screen and remaining two should be smaller than it.
Here I can't use gallery because it is depreciated in android.
I was able to make a gallery like view with help of viewpager using code on this link. It shows only three images on screen at a time, which fits my one requirement. But i am not able to get the central image that is visible on screen and zoom it. Although I was able to get the clicked image on screen.
Can someone please tell me where do I need to modify this code and what I need to add in it to get the image that is in center from the images shown on screen and zoom it.
I know that there is no center image on screen according to viewpager and it is just showing three images on screen at a time because of modifications in code.
I have also tried:-
GridView with horizontal scroll
HorizontalScrollView with horizontal linear layout
but viewpager seems to be a better solution, because it stops the scrolling with only three items on screen because of viewpager's inherent properties.
and If someone knows any other method to achieve it, please tell me and I'll try it.
P.S. For anyone who wants the full code, I have added it as an answer, which has zoom capability also. Just few additions in accepted answer. :)

Following code will help you to make a gallery like view which will have center lock. It responds to touch and swipe both. It shows three images on the screen at a time and the center image is zoomed.
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.HorizontalScrollView;
import android.widget.ImageView;
import android.widget.LinearLayout;
public class CenteringHorizontalScrollView extends HorizontalScrollView implements View.OnTouchListener {
private Context mContext;
private static final int SWIPE_PAGE_ON_FACTOR = 10;
private int mActiveItem;
private float mPrevScrollX;
private boolean mStart;
private int mItemWidth;
View targetLeft, targetRight;
ImageView leftImage, rightImage;
public CenteringHorizontalScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
mContext=context;
mItemWidth = 100; // or whatever your item width is.
setOnTouchListener(this);
}
#Override
public boolean onTouch(View v, MotionEvent event) {
int x = (int) event.getRawX();
boolean handled = false;
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
if (mStart) {
mPrevScrollX = x;
mStart = false;
}
break;
case MotionEvent.ACTION_UP:
mStart = true;
int minFactor = mItemWidth / SWIPE_PAGE_ON_FACTOR;
if ((mPrevScrollX - (float) x) > minFactor) {
if (mActiveItem < getMaxItemCount() - 1) {
mActiveItem = mActiveItem + 1;
}
}else if (((float) x - mPrevScrollX) > minFactor) {
if (mActiveItem > 0) {
mActiveItem = mActiveItem - 1;
}
}
scrollToActiveItem();
handled = true;
break;
}
return handled;
}
private int getMaxItemCount() {
return ((LinearLayout) getChildAt(0)).getChildCount();
}
private LinearLayout getLinearLayout() {
return (LinearLayout) getChildAt(0);
}
/**
* Centers the current view the best it can.
*/
public void centerCurrentItem() {
if (getMaxItemCount() == 0)
return;
int currentX = getScrollX();
View targetChild;
int currentChild = -1;
do {
currentChild++;
targetChild = getLinearLayout().getChildAt(currentChild);
} while (currentChild < getMaxItemCount() && targetChild.getLeft() < currentX);
if (mActiveItem != currentChild) {
mActiveItem = currentChild;
scrollToActiveItem();
}
}
/**
* Scrolls the list view to the currently active child.
*/
private void scrollToActiveItem() {
int maxItemCount = getMaxItemCount();
if (maxItemCount == 0)
return;
int targetItem = Math.min(maxItemCount - 1, mActiveItem);
targetItem = Math.max(0, targetItem);
mActiveItem = targetItem;
// Scroll so that the target child is centered
View targetView = getLinearLayout().getChildAt(targetItem);
ImageView centerImage = (ImageView)targetView;
int height=300;//set size of centered image
LinearLayout.LayoutParams flparams = new LinearLayout.LayoutParams(height, height);
centerImage.setLayoutParams(flparams);
//get the image to left of the centered image
if((targetItem-1)>=0){
targetLeft = getLinearLayout().getChildAt(targetItem-1);
leftImage = (ImageView)targetLeft;
int width=250;//set the size of left image
LinearLayout.LayoutParams leftParams = new LinearLayout.LayoutParams(width,width);
leftParams.setMargins(0, 30, 0, 0);
leftImage.setLayoutParams(leftParams);
}
//get the image to right of the centered image
if((targetItem+1)<maxItemCount){
targetRight = getLinearLayout().getChildAt(targetItem+1);
rightImage = (ImageView)targetRight;
int width=250;//set the size of right image
LinearLayout.LayoutParams rightParams = new LinearLayout.LayoutParams(width,width);
rightParams.setMargins(0, 30, 0, 0);
rightImage.setLayoutParams(rightParams);
}
int targetLeft = targetView.getLeft();
int childWidth = targetView.getRight() - targetLeft;
int width = getWidth() - getPaddingLeft() - getPaddingRight();
int targetScroll = targetLeft - ((width - childWidth) / 2);
super.smoothScrollTo(targetScroll, 0);
}
/**
* Sets the current item and centers it.
* #param currentItem The new current item.
*/
public void setCurrentItemAndCenter(int currentItem) {
mActiveItem = currentItem;
scrollToActiveItem();
}
}
In your xml add the horizontal scroll view like follow:-
<com.yourpackagename.CenteringHorizontalScrollView
android:id="#+id/HSVImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/Horizontalalternative">
<LinearLayout
android:id="#+id/linearImage"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
</LinearLayout>
</com.yourpackagename.CenteringHorizontalScrollView>
Define a Linear layout in your activity.
LinearLayout imageGallery;
Then get it as follows:-
imageGallery=(LinearLayout)findViewById(R.id.linearImage);
Now you have to add imageView to your LinearLayout. Here I assume that you have images in your drawable folder and you have made an array of ids of your images that you want to add to gallery. So you can do it via following method in your activity:-
for(int i=0; i<lengthOfImageIdArray; i++){
ImageView image=new ImageView(YourActivityName.this);
image.setBackgroundResource(yourArrayName[i]);
imageGallery.addView(image);
}
You can also set the width of images dynamically, so that they fit every screen, with only little extra effort.

Override setPrimaryItem in your ViewPager and make the center item bigger.
What was the issue with using a HorizontalScrollView with a LinearLayout? If it's centering you may be able to do something similar to this (assuming you've
/**
* A centering HSV loosely based on http://iotasol.blogspot.com/2011/08/creating-custom-horizontal-scroll-view.html
*/
public class CenteringHorizontalScrollView extends HorizontalScrollView implements View.OnTouchListener {
private static final int SWIPE_PAGE_ON_FACTOR = 10;
private int mActiveItem;
private float mPrevScrollX;
private boolean mStart;
private int mItemWidth;
public CenteringHorizontalScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
mItemWidth = 100; // or whatever your item width is.
setOnTouchListener(this);
}
#Override
public boolean onTouch(View v, MotionEvent event) {
int x = (int) event.getRawX();
boolean handled = false;
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
if (mStart) {
mPrevScrollX = x;
mStart = false;
}
break;
case MotionEvent.ACTION_UP:
mStart = true;
int minFactor = mItemWidth / SWIPE_PAGE_ON_FACTOR;
if ((mPrevScrollX - (float) x) > minFactor) {
if (mActiveItem < getMaxItemCount() - 1) {
mActiveItem = mActiveItem + 1;
}
}
else if (((float) x - mPrevScrollX) > minFactor) {
if (mActiveItem > 0) {
mActiveItem = mActiveItem - 1;
}
}
scrollToActiveItem();
handled = true;
break;
}
return handled;
}
private int getMaxItemCount() {
return ((LinearLayout) getChildAt(0)).getChildCount();
}
private LinearLayout getLinearLayout() {
return (LinearLayout) getChildAt(0);
}
/**
* Centers the current view the best it can.
*/
public void centerCurrentItem() {
if (getMaxItemCount() == 0) {
return;
}
int currentX = getScrollX();
View targetChild;
int currentChild = -1;
do {
currentChild++;
targetChild = getLinearLayout().getChildAt(currentChild);
} while (currentChild < getMaxItemCount() && targetChild.getLeft() < currentX);
if (mActiveItem != currentChild) {
mActiveItem = currentChild;
scrollToActiveItem();
}
}
/**
* Scrolls the list view to the currently active child.
*/
private void scrollToActiveItem() {
int maxItemCount = getMaxItemCount();
if (maxItemCount == 0) {
return;
}
int targetItem = Math.min(maxItemCount - 1, mActiveItem);
targetItem = Math.max(0, targetItem);
mActiveItem = targetItem;
// Scroll so that the target child is centered
View targetView = getLinearLayout().getChildAt(targetItem);
int targetLeft = targetView.getLeft();
int childWidth = targetView.getRight() - targetLeft;
int width = getWidth() - getPaddingLeft() - getPaddingRight();
int targetScroll = targetLeft - ((width - childWidth) / 2);
super.smoothScrollTo(targetScroll, 0);
}
/**
* Sets the current item and centers it.
* #param currentItem The new current item.
*/
public void setCurrentItemAndCenter(int currentItem) {
mActiveItem = currentItem;
scrollToActiveItem();
}
}

Events of more instances of the same custom View

I'm new with Android.
In my project I have the custom View MyView with the follow code
public class MyView extends View {
private final Bitmap baseBitmap = BitmapFactory.decodeResource(
getResources(), R.drawable.myImage);
private final Matrix matrix;
private boolean active = true;
public MyView(Context context, Matrix matrix) {
super(context);
this.matrix = matrix;
this.setFocusable(true);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (active) {
System.out.println("draw "+this.getId());
canvas.drawBitmap(baseBitmap, matrix, null);
} else {
...
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
System.out.println("--------->"+this.getId());
} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
this.matrix.setTranslate(event.getX()-(baseBitmap.getWidth()/2), event.getY()-(baseBitmap.getHeight()/2));
this.invalidate();
} else if (event.getAction() == MotionEvent.ACTION_UP) {
this.active = false;
}
return true;
}
In my Activity, I instantiate MyView many times and then add them to the main layout. This is its code:
public class MyActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Display display = getWindowManager().getDefaultDisplay();
float cx = display.getWidth() / 2, cy = display.getHeight() / 2;
int radius = 80;
double distance = 0, distancePoint = 0;
final int flags = PathMeasure.POSITION_MATRIX_FLAG
| PathMeasure.TANGENT_MATRIX_FLAG;
float length = 0;
setContentView(R.layout.main);
RelativeLayout mainLayout = (RelativeLayout) findViewById(R.id.main_view);
Path pathCircle = new Path();
pathCircle.addCircle(cx, cy, radius, Direction.CW);
PathMeasure meas = new PathMeasure(pathCircle, false);
int nObject = 10;
length = meas.getLength();
distance = length/nObject;
int i = 0;
while(i<nObject){
Matrix m = new Matrix();
meas.getMatrix((float)distancePoint, m, flags);
MyView myView = new MyView(this, m);
System.out.println(myView.toString());
myView.setId(i);
mainLayout.addView(myView,i);
i++;
distancePoint = distance*i;
}
}
}
At runtime, when I touch any MyView element I always get the last. With "System.out.println("--------->"+this.getId());" I can see that the id of the touched element is always the last, even if I toch the first or any other element. Actualy, I just can move the last element.
Does anyone know why can't I get the event of the right istance of MyView touched?
(I hope my question is clear)
Thanks
I changed the code adding the onMeasure method. I used the code of a tutorial, dimensions are not specific for my image. The views are drawn and the result is the same, unfortunately with the same problem. I post the layout xml too, maybe could be useful.
public class MyActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Display display = getWindowManager().getDefaultDisplay();
float cx = display.getWidth() / 2, cy = display.getHeight() / 2;
int radius = 80;
double distance = 0, distancePoint = 0;
final int flags = PathMeasure.POSITION_MATRIX_FLAG
| PathMeasure.TANGENT_MATRIX_FLAG;
float length = 0;
setContentView(R.layout.main);
RelativeLayout mainLayout = (RelativeLayout) findViewById(R.id.main_view);
Path pathCircle = new Path();
pathCircle.addCircle(cx, cy, radius, Direction.CW);
PathMeasure meas = new PathMeasure(pathCircle, false);
int nObject = 10;
length = meas.getLength();
distance = length/nObject;
int i = 0;
while(i<nObject){
Matrix m = new Matrix();
meas.getMatrix((float)distancePoint, m, flags);
MyView myView = new MyView(this, m);
System.out.println(myView.toString());
myView.setId(i);
nt spec = MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED);
myView.measure(spec, spec);
mainLayout.addView(myView,i);
i++;
distancePoint = distance*i;
}
}
}
public class MyView extends View {
private final Bitmap baseBitmap = BitmapFactory.decodeResource(
getResources(), R.drawable.myImage);
private final Matrix matrix;
private boolean active = true;
public MyView(Context context, Matrix matrix) {
super(context);
this.matrix = matrix;
this.setFocusable(true);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (active) {
System.out.println("draw "+this.getId());
canvas.drawBitmap(baseBitmap, matrix, null);
} else {
...
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
System.out.println("--------->"+this.getId());
} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
this.matrix.setTranslate(event.getX()-(baseBitmap.getWidth()/2), event.getY()-(baseBitmap.getHeight()/2));
this.invalidate();
} else if (event.getAction() == MotionEvent.ACTION_UP) {
this.active = false;
}
return true;
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
int chosenWidth = chooseDimension(widthMode, widthSize);
int chosenHeight = chooseDimension(heightMode, heightSize);
int chosenDimension = Math.min(chosenWidth, chosenHeight);
setMeasuredDimension(chosenDimension, chosenDimension);
}
private int chooseDimension(int mode, int size) {
if (mode == MeasureSpec.AT_MOST || mode == MeasureSpec.EXACTLY) {
return size;
} else { // (mode == MeasureSpec.UNSPECIFIED)
return getPreferredSize();
}
}
// in case there is no size specified
private int getPreferredSize() {
return 300;
}
}
The main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout android:id="#+id/main_view"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FF66FF33">
</RelativeLayout>

I'm pretty sure that it's because you're basically piling up your views at the top left corner of your RelativeLayout. So, only the uppermost (the last one added) is touchable.
I think that if you try adding them to a LinearLayout, as a test, you'll see that your view works. Setting LayoutParams for a RelativeLayout programmatically is not very comfy IMHO.
EDIT
I tried your code. The fact is that your views are just made to be drawn one over the other, or else the overall drawing wouldn't come, so my first guess is right (the uppermost covers the others - even in its transparent parts)(btw try Hierarchy Viewer and you can see that yourself). So you need to do your job in a single view, or handle the touches like this:
#Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
if(!isPetaloTouched()) {// check if the actual drawing was touched
return false; // discard the event so that it reaches
// the underlying view
}
//......
See this post for an explanation of how events work in Android.
Both ways would need an isPetaloTouched() logic to detect if/which drawing must be moved, but the first would be more efficient of course.
Also, forget about the onMeasure() thing, I thought that could help giving the view a size around which to wrap, so that it wouldn't fill its parent and aligning views aside would make sense. However, be sure that the touch would work if the views were not piled up.
(...allora mPetali stava proprio per petali!)

Android Drag/Animation of Views

I'm not a programmer, but I'm trying to learn android development, and having a blast.
Lately I've hit a fork in the road, and I don't know that any of the directions I can identify will meet all my needs. This is where you (the experts) can help ;)
Endpoint: I want to have the user touch a ball, and drag it to any location on the screen. I would also like to animate this ball when it gets drawn, and when it gets dropped.
I can accomplish the dragging part using a custom class (that doesn't extend anything... just a class like is found in this tutorial: basic drag & drop, however, I don't know how to apply the tween animation to it since it's not a view.
I have also developed an animated version of an ImageView with my image in it, however, I can't manage to apply the same drag & drop functionality without using AbsoluteLayout, which I know is a no-no.
So... how do I move an ImageView around a ??? layout using MotionEvents, or how do I animate (using tweens defined in XML) a non-view based custom class?
Please ask questions if this is not clear. I don't know all the terminology as well as most of you might.
There is also a copy of this question on the anddev.org forums, so I'll keep this post updated with any responses I get over there.

Why can't you extend View? Then, you have complete control over how it draws because you can override the OnDraw() method. Just make the ColorBall class extend View. Change its position when you move and then invalidate just that one view and have it draw itself instead of having the DrawView class draw it.
Edit - Here is an example class
public class Card extends View
{
private Bitmap mImage;
private final Paint mPaint = new Paint();
private final Point mSize = new Point();
private final Point mStartPosition = new Point();
public Card(Context context)
{
super(context);
}
public final Bitmap getImage() { return mCardImage; }
public final void setImage(Bitmap image)
{
mImage = image;
setSize(mCardImage.getWidth(), mCardImage.getHeight());
}
#Override
protected void onDraw(Canvas canvas)
{
Point position = getPosition();
canvas.drawBitmap(mCardImage, position.x, position.y, mPaint);
}
public final void setPosition(final Point position)
{
mRegion.set(position.x, position.y, position.x + mSize.x, position.y + mSize.y);
}
public final Point getPosition()
{
Rect bounds = mRegion.getBounds();
return new Point(bounds.left, bounds.top);
}
public final void setSize(int width, int height)
{
mSize.x = width;
mSize.y = height;
Rect bounds = mRegion.getBounds();
mRegion.set(bounds.left, bounds.top, bounds.left + width, bounds.top + height);
}
public final Point getSize() { return mSize; }
#Override
public boolean onTouchEvent(MotionEvent event)
{
// Is the event inside of this view?
if(!mRegion.contains((int)event.getX(), (int)event.getY()))
{
return super.onTouchEvent(event);
}
if(event.getAction() == MotionEvent.ACTION_DOWN)
{
mStartPosition.x = (int)event.getX();
mStartPosition.y = (int)event.getY();
bringToFront();
onSelected();
return true;
}
else if(event.getAction() == MotionEvent.ACTION_MOVE)
{
int x = 0, y = 0;
if(mLock == DirectionLock.FREE || mLock == DirectionLock.HORIZONTAL_ONLY)
{
x = (int)event.getX() - mStartPosition.x;
}
if(mLock == DirectionLock.FREE || mLock == DirectionLock.VERTICAL_ONLY)
{
y = (int)event.getY() - mStartPosition.y;
}
mRegion.translate(x, y);
mStartPosition.x = (int)event.getX();
mStartPosition.y = (int)event.getY();
invalidate();
return true;
}
else
{
return super.onTouchEvent(event);
}
}
}