My answer to [this question][1] was just accepted but I started to wonder when exactly one needs to invalidate() a View and when it is not necessary?

After a bit of thinking I came to realization that it _should_ work more or less like this:

  -  actual drawing of &quot;everything&quot; occurs after `onResume()`
  -  in &quot;free&quot; time parts of the screen can be redrawn but only those that were `invalidated` (and everything underneath)

Therefore, it would seem, if I change something after `onResume()` (e.g. as a response to a button click, I should `invalidate()` the changed `View`). 

However, from what scana in [this question][1] says, it must be more complex then that and it depends somethimes on what method one uses.

E.g. on whether one uses

    lastClicked.setImageBitmap();

or

    lastClicked.setImageResource();

So, when it&#39;s necessary to execute invalidate() on a View and how does it really work ?

  [1]: https://stackoverflow.com/questions/10607821/swapping-image-in-imageview/10608396#10608396

When it&#39;s necessary to execute invalidate() on a View?

Is it possible to have just an image popup/come-up in an Android application? It&#39;s similar to an overriding the normal view of an AlertDialog so that it contains just an image and nothing else. 

**SOLUTION:** *I was able to find an answer thanks to @blessenm&#39;s help. Masking an activity as a dialog seems to be the ideal way. The following is the code that I have used.  This dialog styled activity can be invoked as needed by the application the same way a new activity would be started* 

**ImageDialog.java**

    public class ImageDialog extends Activity {
	
	    private ImageView mDialog;
	
	
	    @Override
	    protected void onCreate(Bundle savedInstanceState) {
		    super.onCreate(savedInstanceState);
		    setContentView(R.layout.your_dialog_layout);
		
	
		
		    mDialog = (ImageView)findViewById(R.id.your_image);
		    mDialog.setClickable(true);
		

            //finish the activity (dismiss the image dialog) if the user clicks 
            //anywhere on the image
		    mDialog.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				finish();
			}
		    });
		
	    }
    }



**your_dialog_layout.xml**

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
    &lt;FrameLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
        android:id=&quot;@+id/image_dialog_root&quot; 
        android:layout_width=&quot;wrap_content&quot;
        android:layout_height=&quot;wrap_content&quot;
        android:background=&quot;@android:color/transparent&quot;
        android:gravity = &quot;center&quot;&gt;
   
	    &lt;ImageView
	    	android:id=&quot;@+id/your_image&quot;  
	    	android:layout_width=&quot;wrap_content&quot;
		    android:layout_height=&quot;wrap_content&quot;
		    android:src = &quot;@drawable/your_image_drawable&quot;/&gt;
  
    &lt;/FrameLayout&gt;


*It is crucial that you set the following style for the activity to accomplish this:*

**styles.xml**

      &lt;style name=&quot;myDialogTheme&quot; parent=&quot;@android:style/Theme.Dialog&quot;&gt;
		&lt;item name=&quot;android:windowNoTitle&quot;&gt;true&lt;/item&gt;
		&lt;item name=&quot;android:windowFrame&quot;&gt;@null&lt;/item&gt;
		&lt;item name=&quot;android:background&quot;&gt;@android:color/transparent&lt;/item&gt;
    	&lt;item name=&quot;android:windowBackground&quot;&gt;@android:color/transparent&lt;/item&gt;
    	&lt;item name=&quot;android:windowIsFloating&quot;&gt;true&lt;/item&gt;
    	&lt;item name=&quot;android:backgroundDimEnabled&quot;&gt;false&lt;/item&gt;
    	&lt;item name=&quot;android:windowContentOverlay&quot;&gt;@null&lt;/item&gt;
	   &lt;/style&gt;



*The final step is to declare this style for the activity in the manifest as follows:*


     &lt;activity android:name=&quot;.ImageDialog&quot; android:theme=&quot;@style/myDialogTheme&quot; /&gt;



Android Image Dialog/Popup

I have an `ImageView` with a source image set in the xml using the following syntax:

&lt;!-- language: xml --&gt;

       &lt;ImageView 
          android:id=&quot;@+id/articleImg&quot;
          style=&quot;@style/articleImgSmall_2&quot;
          android:src=&quot;@drawable/default_m&quot; /&gt;

Now I need to change this image programmatically. What I need to do is delete the old image and add a new one though. What I have done is this:

&lt;!-- language: java --&gt;

    myImgView.setBackgroundResource(R.drawable.monkey);

It works but I noticed android stacks the new image on top of the old one (dont ask me how I found out it&#39;s not relevant for the discussion :). I definitely need to get rid of the old one before setting the new image.

How can I achieve that?


Changing ImageView source

I am reusing `ImageView`s for my displays, but at some point I don&#39;t have values to put it.

So how to clear an `ImageView` in Android?

I&#39;ve tried:

    mPhotoView.invalidate();
    mPhotoView.setImageBitmap(null);

None of them have cleared the view, it still shows previous image.

How to clear an ImageView in Android?

I want to add a gradient on the bottom of my image . Something like this :

![enter image description here][1]

I tried something like this but I only get the gradient no image..

        &lt;ImageView
        android:id=&quot;@+id/trendingImageView&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:layout_height=&quot;wrap_content&quot;
        android:background=&quot;@drawable/trend_donald_sterling&quot;
        android:src=&quot;@drawable/trending_gradient_shape&quot;
      /&gt;

trending_gradient_shape:

    &lt;shape xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
           android:shape=&quot;rectangle&quot; &gt;

        &lt;gradient
            android:angle=&quot;90&quot;
            android:endColor=&quot;@android:color/darker_gray&quot;
            android:startColor=&quot;@android:color/darker_gray&quot; /&gt;

        &lt;corners android:radius=&quot;0dp&quot; /&gt;

    &lt;/shape&gt;

 


  [1]: http://i.stack.imgur.com/7soSW.jpg

Add gradient to imageview

I want to check which image resource is attached to `ImageView` in xml, I am  able to check that which image resource is attached to image view but my requirement is to how to check that the `ImageView` has the same resource which I have set into xml or not, based on that I need to perform some actions.Code always executes else part. Following is my code,

  

      if (regProfile.getDrawable() == getResources().getDrawable( R.drawable.ivpic)) 
        {
          Toast.makeText(_con, &quot;Image is ivPic&quot;, Toast.LENGTH_LONG).show(); 
          // new RegisterAsyntaskNew().execute(); 
        } 
      else 
        {
         Toast.makeText(_con, &quot;Image isn&#39;t ivPic&quot;, Toast.LENGTH_LONG).show(); 
         // new RegisterAsyntask().execute(); 
        }

How to check which current image resource is attached to ImageView in android xml?

I need to display three same size images (200 X 100) side by side (no gaps) on top of the screen.  They should occupy entire width of the screen and preserve aspect ratio.
Is it possible to accomplish that using only layout xml file, or I need to use java code?  
Solution shoud be resolution independant...  Can anybody post a solution or link for this (or similar) problem?  Thanks!



How to stretch three images across the screen preserving aspect ratio?

 - I have a `listview`, that has a single `imageview` which is
   scrollable vertically
 - I am trying to place a `textview` on top of `Imageview`
 - Both the views must be visible


----------

 1. Is it possible ?
 2. If yes, How to do it programmatically ?
 3. What changes should i need to make ?

----------


list_view_item_for_images.xml

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
    &lt;RelativeLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
        xmlns:tools=&quot;http://schemas.android.com/tools&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:layout_height=&quot;fill_parent&quot; &gt;
    
        &lt;ImageView
            android:id=&quot;@+id/flag&quot;
            android:layout_width=&quot;fill_parent&quot;
            android:layout_height=&quot;250dp&quot;
            android:layout_alignParentLeft=&quot;true&quot;
            android:layout_alignParentRight=&quot;true&quot;
            android:scaleType=&quot;fitXY&quot;
            android:src=&quot;@drawable/ic_launcher&quot; /&gt;
    
    &lt;/RelativeLayout&gt;


It gives a output like below

![enter image description here][1]



How to do something like below

![enter image description here][2]



note :: Dish 1 &amp; 2 are textviews


  [1]: http://i.stack.imgur.com/dRAl1.png
  [2]: http://i.stack.imgur.com/LixBA.png

Placing a textview on top of imageview in android

I have an Android Application, where I have an `ImageView`, I need to keep the size constant, there can be various images that I need to put into this `ImageView`, of different sizes.

I just need to ensure that all the Images must fit into the `ImageView`,
the Image should increase in size if it is smaller and should decrease, in case it is bigger.

Thanks a lot for your time. 



Android ImageView Fixing Image Size

I am trying to create an ImageView in a Fragment which will refer to the ImageView element which I have created in the XML for the Fragment. However, the `findViewById` method only works if I extend an Activity class. Is there anyway of which I can use it in Fragment as well?

	public class TestClass extends Fragment {
		public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
			ImageView imageView = (ImageView)findViewById(R.id.my_image);
			return inflater.inflate(R.layout.testclassfragment, container, false);
		}
	}

The `findViewById` method has an error on it which states that the method is undefined.

findViewById in Fragment

How could I create a rounded `ImageView` in Android?

I have tried the following code, but it&#39;s not working fine.

Code:

    Bitmap circleBitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);

    BitmapShader shader = new BitmapShader (bitmap,  TileMode.CLAMP, TileMode.CLAMP);
    Paint paint = new Paint();
    paint.setShader(shader);

    Canvas c = new Canvas(circleBitmap);
    c.drawCircle(bitmap.getWidth()/2, bitmap.getHeight()/2, bitmap.getWidth()/2, paint);

    imageView.setImageBitmap(circleBitmap);

Image inside the circle:

![Enter image description here][1]

How can I do this?

  [1]: http://i.stack.imgur.com/x8PhM.png


How to create a circular ImageView in Android?

I get an warning about **[Accessibility]Missing contentDescription attribute on image** in eclipse. This warning show at line 5 (declare `ImageView`) in XML code below.

This not make any error when build and run my application. But I really want to know why i get this warning.

This is my XML file:

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
    &lt;LinearLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
                  android:layout_width=&quot;fill_parent&quot;
                  android:layout_height=&quot;wrap_content&quot;&gt;
        &lt;ImageView
            android:id=&quot;@+id/contact_entry_image&quot;
            android:src=&quot;@drawable/ic_launcher&quot;
            android:layout_width=&quot;wrap_content&quot;
            android:layout_height=&quot;wrap_content&quot;
            /&gt;
        &lt;TextView
            android:id=&quot;@+id/contact_entry_text&quot;
            android:text=&quot;&quot;
            android:layout_width=&quot;fill_parent&quot;
            android:layout_height=&quot;wrap_content&quot;
            android:textSize=&quot;30sp&quot;
            /&gt;
    
    &lt;/LinearLayout&gt;

Please help me regarding this and thanks for your reading.


&#39;Missing contentDescription attribute on image&#39; in XML

Whenever I create an ImageView with icon added using Android Studio&#39;s Vector Assets, I&#39;m getting an error at the line `app:srcCompat=&quot;@drawable/ic_play&quot;`

When I change the `app:srcCompat` with `android:src`, the error is gone but the icon looks pixelated. 

What is the main difference between 

    app:srcCompat=&quot;@drawable/ic_play&quot;

and

    android:src=&quot;@drawable/ic_play&quot;

Difference between app:srcCompat and android:src in Android&#39;s layout XML

I want to set a ripple effect on textview and imageview in Android Studio. How can I do it?


How to set a ripple effect on textview or imageview on Android?

I can&#39;t tell the difference between `ImageView.ScaleType.CENTER_INSIDE` and `ImageView.ScaleType.FIT_CENTER`.

`CENTER_INSIDE`

&gt; Scale the image uniformly (maintain the image&#39;s aspect ratio) so that both dimensions (width and height) of the image will be equal to or less than the corresponding dimension of the view (minus padding). 

`FIT_CENTER`

&gt; Compute a scale that will maintain the original src aspect ratio, but will also ensure that src fits entirely inside dst. At least one axis (X or Y) will fit exactly. The result is centered inside dst.


Can someone illuminate the difference between the two?

What&#39;s the difference between CENTER_INSIDE and FIT_CENTER scale types?

I&#39;m just wondering if there is any significant difference between an `ImageView` that&#39;s set to be clickable, compared with an `ImageButton`?  

Is there any reason for using one over the other? Is there any restriction on the drawable for an `ImageButton` that leaves `ImageView` as the only possible option?  

Will I possibly lose any functionality of a button if I opt for a clickable `ImageView` over `ImageButton`?

Difference between a clickable ImageView and ImageButton

I&#39;m loading a bitmap into an ImageView, and seeing this error. I gather this limit relates to a size limit for OpenGL hardware textures (2048x2048). The image I need to load is a pinch-zoom image of about 4,000 pixels high.

I&#39;ve tried turning off hardware acceleration in the manifest, but no joy.

        &lt;application
            android:hardwareAccelerated=&quot;false&quot;
            ....
            &gt;

Is it possible to load an image larger than 2048 pixels into an ImageView?


&quot;Bitmap too large to be uploaded into a texture&quot;

I have just started learning android. And i don&#39;t know How can I change the image of an `ImageView`? ie it has some Image which was set in the layout but i want to change that image through coding how should i do it ?

Here is the xml file

    &lt;LinearLayout
      xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
      android:layout_width=&quot;fill_parent&quot;
      android:layout_height=&quot;fill_parent&quot;
      android:background=&quot;#cc8181&quot;
     &gt;

    &lt;ImageView
      android:id=&quot;@+id/image&quot;
      android:layout_width=&quot;50dip&quot;
      android:layout_height=&quot;fill_parent&quot; 
      android:src=&quot;@drawable/icon&quot;
      android:layout_marginLeft=&quot;3dip&quot;
      android:scaleType=&quot;center&quot;/&gt;

&lt;/LinearLayout&gt;

thanks for replying.

How can I change the image of an ImageView?

In Android, an ImageView is a rectangle by default. How can I make it a rounded rectangle (clip off all 4 corners of my Bitmap to be rounded rectangles) in the ImageView? 

How to make an ImageView with rounded corners?

Is there really no XML attribute counterpart to `setAlpha(int)`?

If not, what alternatives are there?

Android and setting alpha for (image) view alpha

I have an android application which contains multiple activities. 

In one of them I&#39;m using a button which will call the device camera :
 
    public void onClick(View view) {
        Intent photoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(photoIntent, IMAGE_CAPTURE);
    }

In the same activity I call the `OnActivityResult` method for the image result :

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == IMAGE_CAPTURE) {
            if (resultCode == RESULT_OK) {
                Bitmap image = (Bitmap) data.getExtras().get(&quot;data&quot;);
                ImageView imageview = (ImageView) findViewById(R.id.pic);
                imageview.setImageBitmap(image);
            } else if (resultCode == RESULT_CANCELED) {
                Toast.makeText(this, &quot;CANCELED &quot;, Toast.LENGTH_LONG).show();
            }
        }
    }

The problem is that the intent `data` is null and the `OnActivityResult` method turns directly to the `(resultCode == RESULT_CANCELED)` and the application returns to the previous avtivity.

How can I fix this issue and after calling the camera, the application returns to the current activity which contains an `ImageView` which will contains the picture taken?

Thanks


Android Camera : data intent returns null

I want to Zoom-in and Zoom-out an Android ImageView. I tried most of the samples but in all of them the image in the ImageView itself is getting Zoomed-in and Zoomed-out, while I want to Zoom-in and Zoom-out the ImageView. I want to increase the ImageView width and height while Zooming-in and reduce the ImageView width and height while Zooming-out. How do I achieve that?

Android ImageView Zoom-in and Zoom-Out

In Android, I defined an `ImageView`&#39;s `layout_width` to be `fill_parent` (which takes up the full width of the phone).

If the image I put to `ImageView` is bigger than the `layout_width`, Android will scale it, right? But what about the height? When Android scales the image, will it keep the aspect ratio?

What I find out is that there is some white space at the top and bottom of the `ImageView` when Android scales an image which is bigger than the `ImageView`. Is that true? If yes, how can I eliminate that white space?

How to scale an Image in ImageView to keep the aspect ratio

I have an imageView with an image, over that image I want to place a text. How can I achieve that?

Android Text over image

How do you download and save an image from a given url in Android?

How to download and save an image in Android

I download image and set it as a screen background dynamically using `Imageview`. I have tried `ScaleType`, to scale the image.

If image height is larger than width then `ScaleTypes` `fitStart`, `fitEnd` and `fitCenter` don&#39;t work. Android scale down the photo and fit it based on the height, but I see some extra blank space as part of the width.  

I want to scale down the photo based on the width so that it fits the width and I don&#39;t care if there&#39;s some extra blank space as part of the height or if height is too long it is fine if it&#39;s going out of the view(if that&#39;s possible?).

`ScaleType.XY` scale the photo and fit everything in the `ImageView` and doesn&#39;t care about image height/weight ratio. 

			

    &lt;ImageView 
    				android:id=&quot;@+id/background&quot;
    				android:layout_width=&quot;match_parent&quot;
    				android:layout_height=&quot;match_parent&quot;
    				android:adjustViewBounds=&quot;true&quot;
    				android:scaleType=&quot;fitStart&quot;
    			/&gt;

Android ImageView: Fit Width

So I have an ImageView set with 

    android:maxHeight=&quot;100px&quot;
    android:maxWidth=&quot;250px&quot;
    android:minHeight=&quot;100px&quot;
    android:minWidth=&quot;250px&quot;
    android:scaleType=&quot;centerInside&quot;

This image view is used to show a picture that is obtained from the gallery or camera. In both cases, the image is not resized to fit inside the imageview, it just stretches its space as much as it needs.

Any idea how to make it stay inside those bounds?

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;

&lt;ScrollView
android:id=&quot;@+id/ScrollView01&quot;
android:layout_width=&quot;fill_parent&quot;
android:layout_height=&quot;fill_parent&quot;
xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;&gt;
&lt;RelativeLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
    android:layout_width=&quot;wrap_content&quot;
    android:layout_height=&quot;wrap_content&quot;&gt;

    &lt;EditText
        android:layout_height=&quot;wrap_content&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:id=&quot;@+id/txtDescription&quot;
        android:layout_below=&quot;@+id/txtSubject&quot;
        android:inputType=&quot;textMultiLine&quot;
        android:height=&quot;80px&quot;
        android:hint=&quot;@string/description&quot;&gt;&lt;/EditText&gt;

    &lt;EditText
        android:layout_height=&quot;wrap_content&quot;
        android:layout_below=&quot;@+id/txtDescription&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:id=&quot;@+id/txtMorada&quot;
        android:hint=&quot;@string/address&quot; /&gt;

    &lt;ImageButton
        android:layout_height=&quot;wrap_content&quot;
        android:layout_width=&quot;wrap_content&quot;
        android:layout_below=&quot;@+id/txtMorada&quot;
        android:id=&quot;@+id/btGPS&quot;
        android:layout_alignParentLeft=&quot;true&quot;
        android:src=&quot;@drawable/ic_menu_compass&quot;&gt;&lt;/ImageButton&gt;

    &lt;ImageView
        android:layout_height=&quot;wrap_content&quot;
        android:layout_width=&quot;wrap_content&quot;
        android:layout_below=&quot;@+id/btGPS&quot;
        android:layout_marginTop=&quot;25px&quot;
        android:id=&quot;@+id/imgPoint&quot;
        android:src=&quot;@drawable/google_logo_small&quot;
        android:maxHeight=&quot;100px&quot;
        android:maxWidth=&quot;250px&quot;
        android:minHeight=&quot;100px&quot;
        android:minWidth=&quot;250px&quot;
        android:scaleType=&quot;centerInside&quot;&gt;&lt;/ImageView&gt;

    &lt;ImageButton
        android:layout_height=&quot;wrap_content&quot;
        android:layout_width=&quot;wrap_content&quot;
        android:layout_toRightOf=&quot;@+id/imgPoint&quot;
        android:id=&quot;@+id/btGallery&quot;
        android:layout_below=&quot;@+id/btCamera&quot;
        android:src=&quot;@drawable/ic_menu_gallery&quot;
        android:layout_alignParentRight=&quot;true&quot;&gt;&lt;/ImageButton&gt;

    &lt;Button
        android:layout_height=&quot;wrap_content&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:layout_marginTop=&quot;10px&quot;
        android:id=&quot;@+id/btSubmit&quot;
        android:layout_below=&quot;@+id/btGallery&quot;
        android:text=&quot;@string/submit&quot;&gt;&lt;/Button&gt;

    &lt;ImageButton
        android:layout_height=&quot;wrap_content&quot;
        android:id=&quot;@+id/btMap&quot;
        android:layout_below=&quot;@+id/txtMorada&quot;
        android:layout_width=&quot;wrap_content&quot;
        android:layout_alignParentRight=&quot;true&quot;
        android:src=&quot;@drawable/ic_menu_mapmode&quot;&gt;&lt;/ImageButton&gt;

    &lt;TextView
        android:layout_below=&quot;@+id/txtMorada&quot;
        android:layout_width=&quot;wrap_content&quot;
        android:layout_toLeftOf=&quot;@+id/btMap&quot;
        android:layout_height=&quot;wrap_content&quot;
        android:id=&quot;@+id/lblNewPointLatitude&quot;
        android:text=&quot;Latitude&quot;&gt;&lt;/TextView&gt;

    &lt;TextView
        android:layout_width=&quot;wrap_content&quot;
        android:layout_toLeftOf=&quot;@+id/btMap&quot;
        android:layout_height=&quot;wrap_content&quot;
        android:id=&quot;@+id/lblNewPointLongitude&quot;
        android:layout_below=&quot;@+id/lblNewPointLatitude&quot;
        android:text=&quot;Longitude&quot;&gt;&lt;/TextView&gt;

    &lt;ImageButton
        android:layout_below=&quot;@+id/btMap&quot;
        android:layout_height=&quot;wrap_content&quot;
        android:layout_width=&quot;wrap_content&quot;
        android:layout_toRightOf=&quot;@+is/imgPoint&quot;
        android:id=&quot;@+id/btCamera&quot;
        android:layout_marginTop=&quot;25px&quot;
        android:src=&quot;@drawable/ic_menu_camera&quot;
        android:layout_alignParentRight=&quot;true&quot;&gt;&lt;/ImageButton&gt;

    &lt;Spinner
        android:layout_height=&quot;wrap_content&quot;
        android:id=&quot;@+id/spCategoria&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:prompt=&quot;@string/spCategoriaPrompt&quot;&gt;&lt;/Spinner&gt;

    &lt;Spinner
        android:layout_height=&quot;wrap_content&quot;
        android:id=&quot;@+id/spSubcategoria&quot;
        android:layout_below=&quot;@+id/spCategoria&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:prompt=&quot;@string/spSubcategoriaPrompt&quot;&gt;&lt;/Spinner&gt;

    &lt;EditText
        android:layout_height=&quot;wrap_content&quot;
        android:layout_below=&quot;@+id/spSubcategoria&quot;
        android:layout_width=&quot;fill_parent&quot;
        android:id=&quot;@+id/txtSubject&quot;
        android:hint=&quot;@string/subject&quot;&gt;&lt;/EditText&gt;

      &lt;/RelativeLayout&gt;
    &lt;/ScrollView&gt;




Maximum width and height for ImageView in Android

I&#39;d like to scale an image up to take up the entire size of an ImageView.  This is subtly different than using `scaleType=fit_center` because [fit_center][1] will leave bands around the image if the image aspect ratio does not exactly match the ImageView&#39;s aspect ratio.  Instead, I would like the image to get centered and scaled up to completely fill the enclosing view, with any excess chopped off.

I&#39;m able to accomplish this by computing my own custom image matrix during onCreate():

    final Display display = getWindowManager().getDefaultDisplay();
    final float screenWidth = display.getWidth();
    final float screenHeight = display.getHeight();
    final float imageWidth = splashView.getDrawable().getIntrinsicWidth();
    final float imageHeight = splashView.getDrawable().getIntrinsicHeight();
    final Matrix splashMatrix = new Matrix();
    final float scale = Math.max(screenHeight/imageHeight,screenWidth/imageWidth);
    splashMatrix.postScale( scale, scale );
    splashView.setImageMatrix(splashMatrix);

This works fine, but it seems like there must be  an easier away.  Does anyone know of a way to scale up an image in an ImageView while both preserving the aspect ratio of the image and fully filling in the ImageView?

(Note: in my case my ImageView is taking up the full screen, so I use `getWindowManager().getDisplay()` to find the desired image size.  You can&#39;t use `splashView.getWidth()`/`getHeight()` because the view hasn&#39;t been laid out yet and doesn&#39;t have a size)



  [1]: http://developer.android.com/intl/fr/reference/android/graphics/Matrix.ScaleToFit.html#CENTER

Scale an image up to fill entire ImageView in Android

I have one `ImageView` and set a drawable on it. Now I need to get the ID of the drawable on click event of `ImageView` dynamically. How can I get it?

    imgtopcolor = (ImageView) findViewById(R.id.topcolor); 
    imgtopcolor.setImageResource(R.drawable.dr);  // How do I get this back?

Now on touch event of `imgtopcolor` i want to need drawable id because I am setting different drawable each time and want to compare the drawable with other


Get the ID of a drawable in ImageView

How can I make an ImageView appear in the middle of the screen when the user clicks a button? I have placed the image in the res/drawable-folder.

I&#39;ve been trying with the code below but I don&#39;t know how to make the ImageView appear:
 
     View v = new ImageView(getBaseContext());
     ImageView image; 
     image = new ImageView(v.getContext()); 
     image.setImageDrawable(v.getResources().getDrawable(R.drawable.gameover));

Thanks!


Show ImageView programmatically

I need to show an image by using the file name only, not from the resource id.

     
	ImageView imgView = new ImageView(this);
	imgView.setBackgroundResource(R.drawable.img1);

I have the image img1 in the drawable folder. I wish to show that image from the file. 

How can I do this?  


All Android Imageview Solutions on Gang of Coders

Total of 31 Android Imageview Solutions

When it's necessary to execute invalidate() on a View?