Avoiding object allocations in onDraw() (StaticLayout)? - android

I have a custom view which I quickly learned to not do object allocations in and moved all my Paint allocations into a different method, fine.
I need to use a StaticLayout however for some text that had some spannable 'stuff' applied.
layoutBpm = new StaticLayout(bpmValue,
textPaintBPM, arcRadius, Layout.Alignment.ALIGN_NORMAL, 0, 1,
false);
layoutBpm.draw(canvas);
This seemed to make sense to me to have in onDraw but I am of course getting warned to avoid this. It is important to me that I do everything I can to avoid any performance issues so I am trying to do this properly.
I can't seem to find any documentation I can understand that explains what some of the parameters to StaticLayout actually do (float spacingmult? float spacingadd?), but the third one there I think is maximum width for the StaticLayout text which I can only get from onMeasure as it relates to my canvas size. This leaves me wanting to put the assignment in onMeasure or onDraw, neither of which it seems I am meant to do. Is it okay to put StaticLayout assignment in onDraw or is there a better way to do this?
Hope this makes sense, I am very new to this. Thank you for any help.
(edit: I assume putting this assignment in a method and calling from onDraw/onMeasure is just being silly and will stop Eclipse warning me but wont actually help?)

The reason for the warning is because, very often, you do not need to recreate an object multiple times in a draw operation. onDraw() could be called hundreds of times compared to other methods in a View. Most of the time, the objects being recreated are being recreated with the exact parameters. Other times, it's simply less overhead to change an object's state than it is to create a new object.
In the case of a StaticLayout, you only need to create a new one when the text changes or when you adjust the padding, spacing, or maxwidth. If the text changes often, then you may want to consider DynamicLayout which will remeasure itself every time. Remeasuring costs more overhead than creating a new object, but there's no way it's happening more often than onDraw() calls.
If the text doesn't change often and you absolutely MUST use a StaticLayout, then you can get away with something like this structure.
StaticLayout myLayout;
String textSource = defaultSource;
Paint textPaint = defaultPaint;
int textWidth = defaultWidth;
public CustomView(Context ctx) {
super(ctx);
createLayout();
}
public void setText(String text) {
textSource = text;
createLayout();
}
public void setWidth(int width) {
textWidth = width;
createLayout();
}
#Override
public void onDraw(Canvas canvas) {
myLayout.draw(canvas);
}
private void createLayout() {
myLayout = new StaticLayout(textSource, textPaint, textWidth, Layout.Alignment.ALIGN_NORMAL, 0, 1, false);
}
Basically, you only create a new layout when something changes. Else you just reuse the last object you created.
EDIT:
One way to skip a measure pass is to call View#measure on the newly resized view itself. So your createLayout() method would be something like this.
private void createLayout() {
myLayout = new StaticLayout(textSource, textPaint, textWidth, Layout.Alignment.ALIGN_NORMAL, 0, 1, false);
int textWidthSpec = MeasureSpec.makeMeasureSpec(maxLayoutWidth, MeasureSpec.AT_MOST);
int textHeightSpec = MeasureSpec.makeMeasureSpec(maxLayoutHeight, MeasureSpec.AT_MOST);
myLayout.measure(textWidthSpec, textHeightSpec);
forceLayout();
}
Basically what this does is tells the layout the maximum the View can be. It will measure itself and it's children. The forceLayout() will be invoked on the parent (your custom view) which will re-layout the other contents based on the new measurements.
I should note that I have never done this with a StaticLayout so I have no idea what will happen. It seems like this type of measurement might already be handled when the View is created, but maybe not.
I hope this helps.

Related

Proper way to draw custom view?

I'm trying to implement a custom view that is created by some data - specifically I am trying to create a revenue projection graph via a custom view.
The way i'm doing this is by having 10 data points, and drawing lines between each data point. (and then also drawing the X and Y axis lines).
I was thinking about creating a view that encapsulates the 10 coordinates, and draw them via the canvas in onDraw(). something like this:
class RevView extends View {
private List<Point> mPoints;
public void configurePoints(float[] revenues) {
// convert revenues to points on the graph.
}
// ... constructor... etc.
protected void onDraw(Canvas canvas) {
// use canvas.drawLine to draw line between the points
}
}
but in order to do so, i think i need the width/height of the view, which isn't rendered until onDraw.
is this the right approach? or am i even supposed to pass in a Points list to the view? Or what's a better way to build this?
You should override the onMeasure() method which will be called before onDraw().
https://developer.android.com/reference/android/view/View.html#onMeasure(int,%20int)
Measure the view and its content to determine the measured width and the measured height.
You should use onMeasure() method which is called before onDraw() method, so you'll be able to get your view dimensions like this:
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int width = measureWidth(widthMeasureSpec);
int height = measureHeight(heightMeasureSpec);
}
You should avoid getting View dimensions directly in onDraw() method because it will be called many times a second

Is there any way to create skew animation for a View with ObjectAnimator in android

I want to create skew animation for a View in android.
So, I have rectangular view (this is normal/start state), at the end it should looks like this:
I can do such a thing with android.view.animation package using Transformation of TYPE_MATRIX. So I can create Matrix and use preSkew method, apply this Matrix to my custom animation and then start this animation on a view. So this is OK.
BUT
The problem is I want to do this with ObjectAnimator.
Because using android.view.animation package is not recommended to use.
But I can't get the solution for this problem with ObjectAnimator class.
If I have ImageView, I can use method setImageMatrix for ObjectAnimator (and also create custom MatrixEvaluator to evaluate corresponding matrices for each factor),
but I want to get solution for this problem with a View class, not for some subclass of it.
And the main reason is, that TextView, for example, doesn't have public method like setMatrix, and I want to get the solution for TextView too. So get the solution for base View class is the main desire.
There is another solution: create custom, for example, SkewTextView, in which onDraw method we use canvas.skew method.
But this is worse solution even than using android.view.animation package, because you need to create wrappers for any View subclass you want to skew.
So, I don't know, how I can skew View with a ObjectAnimator (as View class doesn't have public methods like setSkew or setMatrix).
How would you solve this problem?
Have you any idea of how to solve this problem?
Is there a solution for this problem with ObjectAnimator?
Any help (or even thoughts) is greatly appreciated
Thanks
Well without subclassing this might be a bit tricky. My main idea is to use TimeAnimator, which will provide you time callbacks in conjunction with Camera (which can use Matrix transformations). Or you can use TimeAnimator and make a Bitmap from the View you want to skew, make the original View invisible, and draw the Bitmap on each TimeAnimator step applying a Matrix to it. But I'm not sure if this is the optimal way to do that, since you will have to create a new Bitmap on each frame
EDIT: No, Camera approach is not the way to do that as it is stated in comments below
I created a skew animation using Android Property Animation APIs in my project (GitHub Link).
What I did:
Created a custom view (SkewView) and added a SKEW_X property to it.
public class SkewView extends ImageView {
private static final String TAG = "SkewView";
public static final Property SKEW_X
= new FloatProperty("skewX") {
#Override
public void setValue(SkewView object, float value) {
object.setSkewX(value);
}
#Override
public Float get(SkewView object) {
return object.getSkewX();
}
};
private float mSkewX;
// ...
public float getSkewX() {
return mSkewX;
}
public void setSkewX(float skewX) {
mSkewX = skewX;
invalidate();
}
#Override
protected void onDraw(Canvas canvas) {
if (mSkewX != 0) {
canvas.skew((float) (mSkewX * Math.PI / 180.0f), 0);
}
super.onDraw(canvas);
}
}
Used ObjectAnimator to animate this property.
ObjectAnimator skewAnimator = ObjectAnimator.ofFloat(mTarget, SkewView.SKEW_X, 30);

Android: When to call methods that affect child layout upon parent view size change?

I have a very simple RelativeLayout subclass that adds an image view with a text view on top of it. I have a method, show(), which creates and adds the child views and sets the initial text.
At the point I call show() for the first time, the view does not know how big it is, so I can't set the textSize nor the padding for the textView.
I have a solution that mostly works, where I call setTextSize() and setPadding() for the textView within the overridden method, onSizeChanged(). The text does not show the first time it is displayed. However, it shows every time after that, perfectly sized and placed.
Here is the code for onSizeChanged():
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
Log.e(TAG, "onSizeChanged() called");
if (_childTextView != null) {
float textSize = h / 2.0f;
int topPadding = (int)(h / 3.0f);
Log.e(TAG, "setting textSize = " + textSize);
Log.e(TAG, "topPadding = " + topPadding);
_childTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
_childTextView.setPadding(0, topPadding, 0, 0);
}
super.onSizeChanged(w, h, oldw, oldh);
Log.e(TAG, "end onSizeChanged()");
}
The code for show() is as follows:
public void show(int val) {
_val = val;
Log.e(TAG, "in show(), val = " + val);
// create and add background image if not already there
if (_backgroundImageView == null) {
_backgroundImageView = new ImageView(_context);
_backgroundImageView.setImageResource(R.drawable.background);
LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
params.addRule(CENTER_IN_PARENT);
addView(_backgroundImageView, params);
}
// create and add text view if not already there
if (_childTextView == null) {
_childTextView = new TextView(_context);
_childTextView.setTextColor(Color.BLACK);
LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.addRule(CENTER_HORIZONTAL);
addView(_childTextView, params);
}
Log.e(TAG, "setting text to: " + _val);
// update value and make visible
_childTextView.setText(String.valueOf(_val));
setVisibility(VISIBLE);
Log.e(TAG, "end show()");
}
The background image displays correctly every time. The textView only displays correctly the second time show() is called and afterwards. Logging in onSizeChanged() shows that the calculated numbers are correct the first time. As expected, onSizeChanged() only gets called the first time, a bit after we return from show(). Subsequent calls to show() just set the value and visibility, and the text is displayed correctly.
My question is: is there a better way to do this? Or a better callback method to override?
Trying to set these values in show() doesn't work because the main view doesn't yet know its own size (at least the first time). I have tried putting invalidate() at the end of onSizeChanged(). I have also tried putting the call to setText() there.
I need to be able to do this based on size, because this class is reused in different contexts where the image needs to be smaller or larger.
Thank you for any insight you can give. I'd really like to keep this simple if possible.
Edit: What I am trying to do is size some text to be about 1/2 the size of the child image (which is the same as the parent size), and to have top padding set to about 1/3 of the image size. This would be easy if I just wanted it to be one size. However, I want it to be size-adjustable based on the needs of the display.
Imagine a postage stamp, where you want to place the value somewhere precisely in the image. So far so good. But what if this postage stamp needs to be displayed at different sizes on the same phone? You'd want both the placement offset (the padding) and the text size to adjust accordingly. If I hardcode this into the xml, then the text size and placement will not be adjusted when I size the layout. The text will be too big on the small version, and will be placed too far from the top of the image.
i have no idea why you override onSizeChanged(), normaly android handles all this nicely if you use it the way it is intendet.
can you pls explain what you want to achive - maybe with example picture?
however i wondered that you don't override onMesure() when you override the rest and if a delayed call to show() helps it also might be because of onMesure is called in between.
edit:
in android you should never want to know a real size of some views. nearly every device has other sizes and there is portrait/landscape mode too. if you start coding vs real sizes you can give up at the start. instead you should use something more relative like dp and sp than you should never again worry about text sizes and similar.
you may also want and you should use LayoutInflater and xml files as much as possible in your application. in a Activity you can call setContentView(). in other cases there might be methods to overload like onCreateView. and if you have nothing else you can do it like this:
LayoutInflater inflater = LayoutInflater.from(contextEgActivity);
View rootView = inflater.inflate(R.layout.highscore_daily, parentCanBeNull);
edit II:
so this is what you want - right? (on the ImageView and the TextView it would be even better to use wrap_content for height and width)
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:layout_width="200dp"
android:layout_height="200dp"
android:id="#+id/imageView"
android:layout_gravity="center"
android:background="#ff0000" />
<TextView
android:layout_width="100dp"
android:layout_height="100dp"
android:text="New Text"
android:id="#+id/textView"
android:layout_gravity="center"
android:background="#00ff00"
android:textSize="20sp" />
</FrameLayout>
if you only have ~3 different sizes i would write 3 different xml files to match what you want. otherwise i think this code will fit your needs.
//http://stackoverflow.com/questions/4605527/converting-pixels-to-dp
public static float convertDpToPixel(float dp, Context context){
Resources resources = context.getResources();
DisplayMetrics metrics = resources.getDisplayMetrics();
float px = dp * (metrics.densityDpi / 160f);
return px;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);//loads the xml above
ImageView v = (ImageView) findViewById(R.id.imageView);
int dp = 200;
int px = (int) convertDpToPixel(dp, this);
v.setMaxHeight(px);//no need for it
v.setMinimumHeight(px);//should do more or less the same as next line
v.setLayoutParams(new LinearLayout.LayoutParams(px, px));//is like android:layout_width="200dp" android:layout_height="200dp"
v.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, px));//is like android:layout_width="wrap_content" android:layout_height="200dp"
//basically you can do the same with the TextView + the Text styling
TextView tv = (TextView) findViewById(R.id.textView);
tv.setTextSize(TypedValue.COMPLEX_UNIT_SP, 50);
tv.setPadding(30,30,30,30);//don't forget, this is also px so you may need dp to px conversion
}
this is the normal way, nice clean and easy. if you why ever still want to react on size changes of your parent you can try this but i don't suggest it. btw changing view stuff should only be executed from ui/main thread so if the method gets called from a other thread thry a Handler like new Handler(getMainLooper)

Requirements for a custom android View

I'm interested in using a custom View to draw, measure, and display a set of buttons that is dependent on a back-end for my application. This requires me to implement this in Android dynamically. Would you help me get started?
Here we go: first in my MainActivity I instantiate my custom class which inherits from TableLayout which is also a view:
var keyboardView = new KeyboardView(this, layout, droidLayout, this.Colors);
Then I set the content view to the fresh instance of my custom class: SetContentView(keyboardView); Here's my class's constructor which just helps me get scope on all of the info I need:
public KeyboardView(Context context, KeyboardLayout layout, int droidLayout, Dictionary<string, int> colors)
: base(context) {
this._Colors = colors;
this._Context = context;
this.KeyboardLayout = layout;
this.SetWillNotDraw(false);
//this.ButtonLayout = ll;
this.DrawingCacheEnabled = true;
this.DroidLayout = droidLayout;
I've also overridden both OnMeasure and OnDraw:
protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int h = 100;
int w = 100;
//Overall keyboard/View dimensions //Difference between Canvas size and KeyboardDimensions?
this.SetMeasuredDimension(w, h);
//this.Layout.CanvasSize.
}
protected override void OnDraw(Canvas canvas) {
var bt = new Button(this._Context);
bt.Text = "laaaa";
this.AddView(bt);
}
Now what's happening is that OnDraw and OnMeasure both get it, in fact, OnDraw seems to be getting hit lots of time -- more so then I wish to count. However, the one button that I added via AddView is NOT drawn on the screen. If you guys could help me get this one button on the screen I can get to writing the core logic!
On a side-note: I can draw stuff on my screen if I set an XML layout file as the view as such: SetContentView(Resource.Layout.LayoutName) But, since the nature of my program requires dynamic views being added all the time, I'd rather avoid writing lengthy Layout files. Thanks guys! Bump my question up if you think it's a worthwhile one!
In general, this is a good place to start. In particular it details how to add custom attributes, how to perform custom drawing, and how to design custom events that make sense in the context of your own application.
Also, it looks like you're trying to use C# style syntax in Java, which won't work for things like inheritance. Reading some java tutorials might help you out.
This is a good resource for that and should help you get up and going. Good luck!
Don't forget to call the super() to allow the parent class to do what it needs to do for the overridden method.
protected override void OnDraw(Canvas canvas) {
super(canvas)
}
Related link
http://developer.android.com/guide/topics/ui/custom-components.html#compound

How to retrieve the dimensions of a view?

I have a view made up of TableLayout, TableRow and TextView. I want it to look like a grid. I need to get the height and width of this grid. The methods getHeight() and getWidth() always return 0. This happens when I format the grid dynamically and also when I use an XML version.
How to retrieve the dimensions for a view?
Here is my test program I used in Debug to check the results:
import android.app.Activity;
import android.os.Bundle;
import android.widget.TableLayout;
import android.widget.TextView;
public class appwig extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.maindemo); //<- includes the grid called "board"
int vh = 0;
int vw = 0;
//Test-1 used the xml layout (which is displayed on the screen):
TableLayout tl = (TableLayout) findViewById(R.id.board);
tl = (TableLayout) findViewById(R.id.board);
vh = tl.getHeight(); //<- getHeight returned 0, Why?
vw = tl.getWidth(); //<- getWidth returned 0, Why?
//Test-2 used a simple dynamically generated view:
TextView tv = new TextView(this);
tv.setHeight(20);
tv.setWidth(20);
vh = tv.getHeight(); //<- getHeight returned 0, Why?
vw = tv.getWidth(); //<- getWidth returned 0, Why?
} //eof method
} //eof class
I believe the OP is long gone, but in case this answer is able to help future searchers, I thought I'd post a solution that I have found. I have added this code into my onCreate() method:
EDITED: 07/05/11 to include code from comments:
final TextView tv = (TextView)findViewById(R.id.image_test);
ViewTreeObserver vto = tv.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
LayerDrawable ld = (LayerDrawable)tv.getBackground();
ld.setLayerInset(1, 0, tv.getHeight() / 2, 0, 0);
ViewTreeObserver obs = tv.getViewTreeObserver();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
obs.removeOnGlobalLayoutListener(this);
} else {
obs.removeGlobalOnLayoutListener(this);
}
}
});
First I get a final reference to my TextView (to access in the onGlobalLayout() method). Next, I get the ViewTreeObserver from my TextView, and add an OnGlobalLayoutListener, overriding onGLobalLayout (there does not seem to be a superclass method to invoke here...) and adding my code which requires knowing the measurements of the view into this listener. All works as expected for me, so I hope that this is able to help.
I'll just add an alternative solution, override your activity's onWindowFocusChanged method and you will be able to get the values of getHeight(), getWidth() from there.
#Override
public void onWindowFocusChanged (boolean hasFocus) {
// the height will be set at this point
int height = myEverySoTallView.getMeasuredHeight();
}
You are trying to get width and height of an elements, that weren't drawn yet.
If you use debug and stop at some point, you'll see, that your device screen is still empty, that's because your elements weren't drawn yet, so you can't get width and height of something, that doesn't yet exist.
And, I might be wrong, but setWidth() is not always respected, Layout lays out it's children and decides how to measure them (calling child.measure()), so If you set setWidth(), you are not guaranteed to get this width after element will be drawn.
What you need, is to use getMeasuredWidth() (the most recent measure of your View) somewhere after the view was actually drawn.
Look into Activity lifecycle for finding the best moment.
http://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle
I believe a good practice is to use OnGlobalLayoutListener like this:
yourView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
if (!mMeasured) {
// Here your view is already layed out and measured for the first time
mMeasured = true; // Some optional flag to mark, that we already got the sizes
}
}
});
You can place this code directly in onCreate(), and it will be invoked when views will be laid out.
Use the View's post method like this
post(new Runnable() {
#Override
public void run() {
Log.d(TAG, "width " + MyView.this.getMeasuredWidth());
}
});
I tried to use onGlobalLayout() to do some custom formatting of a TextView, but as #George Bailey noticed, onGlobalLayout() is indeed called twice: once on the initial layout path, and second time after modifying the text.
View.onSizeChanged() works better for me because if I modify the text there, the method is called only once (during the layout pass). This required sub-classing of TextView, but on API Level 11+ View. addOnLayoutChangeListener() can be used to avoid sub-classing.
One more thing, in order to get correct width of the view in View.onSizeChanged(), the layout_width should be set to match_parent, not wrap_content.
Are you trying to get sizes in a constructor, or any other method that is run BEFORE you get the actual picture?
You won't be getting any dimensions before all components are actually measured (since your xml doesn't know about your display size, parents positions and whatever)
Try getting values after onSizeChanged() (though it can be called with zero), or just simply waiting when you'll get an actual image.
As F.X. mentioned, you can use an OnLayoutChangeListener to the view that you want to track itself
view.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
#Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
// Make changes
}
});
You can remove the listener in the callback if you only want the initial layout.
I guess this is what you need to look at: use onSizeChanged() of your view. Here is an EXTENDED code snippet on how to use onSizeChanged() to get your layout's or view's height and width dynamically http://syedrakibalhasan.blogspot.com/2011/02/how-to-get-width-and-height-dimensions.html
ViewTreeObserver and onWindowFocusChanged() are not so necessary at all.
If you inflate the TextView as layout and/or put some content in it and set LayoutParams then you can use getMeasuredHeight() and getMeasuredWidth().
BUT you have to be careful with LinearLayouts (maybe also other ViewGroups). The issue there is, that you can get the width and height after onWindowFocusChanged() but if you try to add some views in it, then you can't get that information until everything have been drawn. I was trying to add multiple TextViews to LinearLayouts to mimic a FlowLayout (wrapping style) and so couldn't use Listeners. Once the process is started, it should continue synchronously. So in such case, you might want to keep the width in a variable to use it later, as during adding views to layout, you might need it.
Even though the proposed solution works, it might not be the best solution for every case because based on the documentation for ViewTreeObserver.OnGlobalLayoutListener
Interface definition for a callback to be invoked when the global layout state or the visibility of views within the view tree changes.
which means it gets called many times and not always the view is measured (it has its height and width determined)
An alternative is to use ViewTreeObserver.OnPreDrawListener which gets called only when the view is ready to be drawn and has all of its measurements.
final TextView tv = (TextView)findViewById(R.id.image_test);
ViewTreeObserver vto = tv.getViewTreeObserver();
vto.addOnPreDrawListener(new OnPreDrawListener() {
#Override
public void onPreDraw() {
tv.getViewTreeObserver().removeOnPreDrawListener(this);
// Your view will have valid height and width at this point
tv.getHeight();
tv.getWidth();
}
});
Height and width are zero because view has not been created by the time you are requesting it's height and width . One simplest solution is
view.post(new Runnable() {
#Override
public void run() {
view.getHeight(); //height is ready
view.getWidth(); //width is ready
}
});
This method is good as compared to other methods as it is short and crisp.
You should rather look at View lifecycle: http://developer.android.com/reference/android/view/View.html Generally you should not know width and height for sure until your activity comes to onResume state.
You can use a broadcast that is called in OnResume ()
For example:
int vh = 0;
int vw = 0;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.maindemo); //<- includes the grid called "board"
registerReceiver(new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
TableLayout tl = (TableLayout) findViewById(R.id.board);
tl = (TableLayout) findViewById(R.id.board);
vh = tl.getHeight();
vw = tl.getWidth();
}
}, new IntentFilter("Test"));
}
protected void onResume() {
super.onResume();
Intent it = new Intent("Test");
sendBroadcast(it);
}
You can not get the height of a view in OnCreate (), onStart (), or even in onResume () for the reason that kcoppock responded
Simple Response: This worked for me with no Problem.
It seems the key is to ensure that the View has focus before you getHeight etc. Do this by using the hasFocus() method, then using getHeight() method in that order. Just 3 lines of code required.
ImageButton myImageButton1 =(ImageButton)findViewById(R.id.imageButton1);
myImageButton1.hasFocus();
int myButtonHeight = myImageButton1.getHeight();
Log.d("Button Height: ", ""+myButtonHeight );//Not required
Hope it helps.
Use getMeasuredWidth() and getMeasuredHeight() for your view.
Developer guide: View
CORRECTION:
I found out that the above solution is terrible. Especially when your phone is slow.
And here, I found another solution:
calculate out the px value of the element, including the margins and paddings:
dp to px:
https://stackoverflow.com/a/6327095/1982712
or dimens.xml to px:
https://stackoverflow.com/a/16276351/1982712
sp to px:
https://stackoverflow.com/a/9219417/1982712 (reverse the solution)
or dimens to px:
https://stackoverflow.com/a/16276351/1982712
and that's it.

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