I found two ways of creating a Bitmap from a view. But once I do that, the view disappears and I can't use it anymore. How can I redraw the view after generating my bitmap?
1st:
public static Bitmap getBitmapFromView(View view) {
Bitmap returnedBitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(),Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(returnedBitmap);
Drawable bgDrawable =view.getBackground();
if (bgDrawable!=null)
bgDrawable.draw(canvas);
else
canvas.drawColor(Color.WHITE);
view.draw(canvas);
return returnedBitmap;
}
2nd:
Bitmap viewCapture = null;
theViewYouWantToCapture.setDrawingCacheEnabled(true);
viewCapture = Bitmap.createBitmap(theViewYouWantToCapture.getDrawingCache());
theViewYouWantToCapture.setDrawingCacheEnabled(false);
EDIT
So, I think I understand what happens on the first one, we are basically removing the view from it's original canvas and drawing it somewhere else associated with that bitmap. Can somehow we store the original canvas and then set the view to be redrawn there?
Sorry, I'm not immensely knowledgeable on this. But I use the following code:
public Bitmap getBitmapFromView(View view, int width, int height) {
Bitmap returnedBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(returnedBitmap);
Drawable bgDrawable = view.getBackground();
if (view==mainPage.boardView) {
canvas.drawColor(BoardView.BOARD_BG_COLOR);
} else if (bgDrawable!=null) {
bgDrawable.draw(canvas);
} else {
canvas.drawColor(Color.WHITE);
}
view.measure(MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY));
view.layout(0, 0, width, height);
view.draw(canvas);
return returnedBitmap;
}
which is so similar to yours I suspect we copy&edited from the same place.
I have no trouble with the view disappearing from the original drawing tree. Mine is called for ViewGroups rather than plain Views.
Try this.
Getting the bitmap:
// Prepping.
boolean oldWillNotCacheDrawing = view.willNotCacheDrawing();
view.setWillNotCacheDrawing(false);
view.setDrawingCacheEnabled(true);
// Getting the bitmap
Bitmap bmp = view.getDrawingCache();
And make sure to reset the view back to its old self.
view.destroyDrawingCache();
view.setDrawingCacheEnabled(false);
view.setWillNotCacheDrawing(oldWillNotCacheDrawing);
return bmp;
Guy's answer works when the View has not yet been laid out in a parent view.
If the view already has been measured and laid out in a parent-view, Guy's answer may screw up your Activity's layout.
If the view hasn't yet been measured and laid out, Guy's answer works fine.
My answer would work after the View has been laid out and it won't screw up the Activity's layout since it doesn't measure and layout the View again.
Related
I would like to ask help. I want to take screenshot. This is working, but ImageView rounded corners are not rounded on the taken screenshots (and elevation shadows missing too). I used
imageView.setClipToOutline(true);
to make this work on the phone, but on the screenshots they are rectangular.
These are my screenshot utils:
public class ScreenShotUtils {
public static Bitmap screenShotFromCanvas(View view) {
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(),
view.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
view.draw(canvas);
return bitmap;
}
public static Bitmap screenShotFromDrawingCache(View view) {
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
Bitmap bitmap = Bitmap.createBitmap(view.getDrawingCache());
view.destroyDrawingCache();
view.setDrawingCacheEnabled(false);
return bitmap;
}
Both method has the same result.
However i noticed, that if i turn the hardware acceleration off, the layout looks like the same as on the screenshots.
This is how it looks like after take screenshot:
This is how it should be:
Finally i solved my problem with MediaProjectionManager.
I want to take a picture of a view in Activity and share this picture.
First I use this method :
private Bitmap getShareViewShot() {
this.setDrawingCacheEnabled(true);
this.buildDrawingCache();
Bitmap bitmap = Bitmap.createBitmap(this.getDrawingCache(), 0, mSharePageRoot.getTop(), this.getWidth(), mSharePageRoot.getBottom());
this.setDrawingCacheEnabled(false);
return bitmap;
}
But if the view is in a ScrollView and the view has scrolled outside the screen, this method can't get a whole picture of this view.
So I change this method to below :
private Bitmap getShareViewShot() {
Bitmap bitmap = Bitmap.createBitmap(mSharePageRoot.getWidth(), mSharePageRoot.getHeight(),
Bitmap.Config.ARGB_8888);
mSharePageRoot.layout(0, 0, mSharePageRoot.getLayoutParams().width, mSharePageRoot.getLayoutParams().height);
final Canvas canvas = new Canvas(bitmap);
mSharePageRoot.draw(canvas);
return bitmap;
}
But another question comes: this view has no backgroud, so the picture I get has a black backgroud.In my code ,the Activity have a network image as the backgroud, so this means this method can't get the backgroud of the activity.
Please forgive me for my bad English.
Is there any other method ? thanks.
Yes, there is another method. There is a library by google called ASL(Android screenshot library). It's pretty simple.
https://code.google.com/archive/p/android-screenshot-library/wikis/DeveloperGuide.wiki
You can draw background by canvas, like this:
private Bitmap getShareViewShot() {
Bitmap bitmap = Bitmap.createBitmap(mSharePageRoot.getWidth(), mSharePageRoot.getHeight(),
Bitmap.Config.ARGB_8888);
mSharePageRoot.layout(0, 0, mSharePageRoot.getLayoutParams().width, mSharePageRoot.getLayoutParams().height);
final Canvas canvas = new Canvas(bitmap);
// the bitmap will have a white background
canvas.drawColor(0xffffffff);
mSharePageRoot.draw(canvas);
return bitmap;
}
I'm trying to save the path that is being drawn on a View but I just can't figure out how to do this.
Here is what I'm doing in my Activity to create the View and set it as content:
View accPathView = new AccPathView(this, steps);
setContentView(accPathView);
Then in the onDraw method of my View class, I'm simply creating a path and drawing it on the canvas I received as parameter:
But then, when I try to get the bitmap of my view with getDrawingCache(), it's always null and creates an empty image on my SD. I tried
accPathView.setDrawingCacheEnabled(true);
accPathView.buildDrawingCache(true);
Unfortunately it didn't change anything and I still get an empty bitmap.
You may try this:
public static Bitmap getBitmapFromView(View view) {
//Define a bitmap with the same size as the view
Bitmap returnedBitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(),Bitmap.Config.ARGB_8888);
//Bind a canvas to it
Canvas canvas = new Canvas(returnedBitmap);
//Get the view's background
Drawable bgDrawable =view.getBackground();
if (bgDrawable!=null)
//has background drawable, then draw it on the canvas
bgDrawable.draw(canvas);
else
//does not have background drawable, then draw white background on the canvas
canvas.drawColor(Color.WHITE);
// draw the view on the canvas
view.draw(canvas);
//return the bitmap
return returnedBitmap;
}
EDIT:
How do you the above method?
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
View accPathView = new AccPathView(this, steps);
setContentView(accPathView);
accPathView.post(new Runnable() {
public void run() {
Bitmap viewBitmap = getBitmapFromView(accPathView);
}
});
// your remaining oncreate
}
In my code, I have a LinearLayout with many TextViews (like a table). And I try to convert this to Bitmap. there is my code:
public static Bitmap convertToBitmap(LinearLayout view){
view.measure(LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(),
view.getHeight(),
Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(bitmap);
view.draw(c);
return bitmap;
}
But, there is a problem.
Views witch has setSingleLine(true) not display text in bitmap.
Exactly, the problem is in setHorizontallyScrolling(true), which is calling in setSingleLine code...
I try use .setScrollTo(X), but what exactly X must be. X = 0 - not works.
Is there any, who knows how fix it?
EDIT: TextViews has fixed Width.
EDIT: Problem is only for TextViews with Gravity = Center. With gravity Left all's ok.
Try one of this code? It's a bit different from the one you posted above.
/**
* this actually also provided by Romain Guy, but let's try another for performance improvements
*/
public static Bitmap getBitmapFromView(View view, int width, int height) {
view.measure(View.MeasureSpec.makeMeasureSpec(width, View.MeasureSpec.EXACTLY),
View.MeasureSpec.makeMeasureSpec(height, View.MeasureSpec.EXACTLY));
view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
// Build the Drawing Cache
view.buildDrawingCache();
// Create Bitmap
Bitmap drawingCache = view.getDrawingCache();
if (drawingCache == null) {
return null;
}
Bitmap bitmap = Bitmap.createBitmap(drawingCache);
drawingCache.recycle();
view.setDrawingCacheEnabled(false);
return bitmap;
}
/**
* This method provided by Romain Guy, so it should do the job better, especially it includes case for listViews
*/
public static Bitmap getBitmapFromView(View view, int width, int height) {
//Pre-measure the view so that height and width don't remain null.
view.measure(View.MeasureSpec.makeMeasureSpec(width, View.MeasureSpec.EXACTLY), View.MeasureSpec.makeMeasureSpec(height, View.MeasureSpec.EXACTLY));
//Assign a size and position to the view and all of its descendants
view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
// Create bitmap
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.RGB_565);
//Create a canvas with the specified bitmap to draw into
Canvas canvas = new Canvas(bitmap);
// if it's scrollView we get gull size
canvas.translate(-view.getScrollX(), -view.getScrollY());
//Render this view (and all of its children) to the given Canvas
view.draw(canvas);
return bitmap;
}
I have a LinearLayout that contains a lot of sub LinearLayouts which contain TextViews. I want to get a screenshot from the parent LinearLayout to get a full view of my "Receipt". So I tried to do that:
View v = findViewById(R.id.llReceipt);
v.setDrawingCacheEnabled(true);
Bitmap b = v.getDrawingCache();
the problem is the Bitmap b get a null value.
Is there any solution to solve it?
I don't know why your bitmap is null but I've used this bit before to get a screen shot of a custom view and it worked:
public Bitmap getBitmapFromView(View view, int width, int height) {
Bitmap returnedBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(returnedBitmap);
Drawable bgDrawable = view.getBackground();
if (view==mainPage.boardView) {
canvas.drawColor(BoardView.BOARD_BG_COLOR);
} else if (bgDrawable!=null) {
bgDrawable.draw(canvas);
} else {
canvas.drawColor(Color.WHITE);
}
view.measure(MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY));
view.layout(0, 0, width, height);
view.draw(canvas);
return returnedBitmap;
}
Taken from here!
I found my problem:
I called the getScreenShot() Function from the onCreate() Function which doesn't work.
it should call it after this step.