convert a textview, including those contents off the screen, to bitmap - android

I want to save(export) contents of MyView, which extends TextView, into a bitmap.
I followed the code: [this][1].
It works fine when the size of the text is small.
But when there are lots of texts, and some of the content is out of the screen, what I got is only what showed in the screen.
Then I add a "layout" in my code:
private class MyView extends TextView{
public MyView(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
public Bitmap export(){
Layout l = getLayout();
int width = l.getWidth() + getPaddingLeft() + getPaddingRight();
int height = l.getHeight() + getPaddingTop() + getPaddingBottom();
Bitmap viewBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(viewBitmap);
setCursorVisible(false);
layout(0, 0, width, height);
draw(canvas);
setCursorVisible(true);
return viewBitmap;
}
}
Now the strange thing happened:
The first time I invoke "export"(I use an option key to do that), I got contents only on the screen.
When I invoke "export" again, I got complete contents, including those out of the screen.
Why?
How to "export" a view, including contents cannot be showed on the screen?
Thank you!
[1]: http://www.techjini.com/blog/2010/02/10/quicktip-how-to-convert-a-view-to-an-image-android/ this


I found out a simpler way:
Put the TextView in a ScrollView.
Now myTextView.draw(canvas) will draw all of the text.


I think you should be subtracting the padding from the width in the height instead of adding it. Adding it will give you an area larger than the screen.


I solved this issue this way(strange but works):
public Bitmap export(){
//...
LayoutParams lp = getLayoutParams();
int old_width = lp.width;
int old_height = lp.height;
int old_scroll_x = getScrollX();
int old_scroll_y = getScrollY();
lp.width = width;
lp.height = height;
layout(0, 0, width, height);
scrollTo(0, 0);
draw(canvas);
lp.width = old_width;
lp.height = old_height;
setLayoutParams(lp);
scrollTo(old_scroll_x, old_scroll_y);
//...
}

Related

Getting height of text view before rendering to layout

Could not find any good solution calculating textview height where text was set before rendering textview to layout. Any help please

2 solutions
Used solution 1 at first and found solution 2 later on. Both work, it's really what you prefer.
Important is to make sure you got all the dimensions right since mixing font sizes in sp or px will give quite a difference depending on what screen you test on.
A very basic example project is available at https://github.com/hanscappelle/SO-3654321
Solution 1 using TextView and MeasureSpec
Main issue with original question is TextView in below method should be configured as our TextView which should be rendered to layout. I think this solution is valuable for many people who faced this problem.
public static int getHeight(Context context, CharSequence text, int textSize, int deviceWidth, Typeface typeface,int padding) {
TextView textView = new TextView(context);
textView.setPadding(padding,0,padding,padding);
textView.setTypeface(typeface);
textView.setText(text, TextView.BufferType.SPANNABLE);
textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, textSize);
int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(deviceWidth, View.MeasureSpec.AT_MOST);
int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
textView.measure(widthMeasureSpec, heightMeasureSpec);
return textView.getMeasuredHeight();
}
And an example of how to use this:
// retrieve deviceWidth
int deviceWidth;
WindowManager wm = (WindowManager) textView.getContext().getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
if(android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2){
Point size = new Point();
display.getSize(size);
deviceWidth = size.x;
} else {
deviceWidth = display.getWidth();
}
// the text to check for
String exampleTextToMeasure = "some example text that will be long enough to make this example split over multiple lines so we can't easily predict the final height";
// some dimensions from dimes resources to take into account
int textSize = getContext().getResources().getDimensionPixelSize(R.dimen.text_size);
int padding = getContext().getResources().getDimensionPixelSize(R.dimen.text_padding);
// final calculation of textView height
int measuredTextHeight = getHeight(getContext(), exampleTextToMeasure, textSize, deviceWidth, TypeFace.DEFAULT, padding);
Solution 2 using TextPaint and StaticLayout
This method relies on a TextPaint and StaticLayout which also gives reliable results on all API levels I've tested so far. Pay good attention to units of dimensions; all should be in pixels!
Source: Measuring text height to be drawn on Canvas ( Android )
public static int method1UsingTextPaintAndStaticLayout(
final CharSequence text,
final int textSize, // in pixels
final int deviceWidth, // in pixels
final int padding // in pixels
) {
TextPaint myTextPaint = new TextPaint();
myTextPaint.setAntiAlias(true);
// this is how you would convert sp to pixels based on screen density
//myTextPaint.setTextSize(16 * context.getResources().getDisplayMetrics().density);
myTextPaint.setTextSize(textSize);
Layout.Alignment alignment = Layout.Alignment.ALIGN_NORMAL;
float spacingMultiplier = 1;
float spacingAddition = padding; // optionally apply padding here
boolean includePadding = padding != 0;
StaticLayout myStaticLayout = new StaticLayout(text, myTextPaint, deviceWidth, alignment, spacingMultiplier, spacingAddition, includePadding);
return myStaticLayout.getHeight();
}

From support_ms answer, there is a more simple method that take only a TextView as parameter.
/**
* Get the TextView height before the TextView will render
* #param textView the TextView to measure
* #return the height of the textView
*/
public static int getTextViewHeight(TextView textView) {
WindowManager wm =
(WindowManager) textView.getContext().getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
int deviceWidth;
if(android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2){
Point size = new Point();
display.getSize(size);
deviceWidth = size.x;
} else {
deviceWidth = display.getWidth();
}
int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(deviceWidth, View.MeasureSpec.AT_MOST);
int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
textView.measure(widthMeasureSpec, heightMeasureSpec);
return textView.getMeasuredHeight();
}

Good answer from #support_ms, but I'm not sure of the point of creating a new TextView and working out all of this input params when you could just format your TextView first and then call the static method with just one parameter, the TextView itself!
Also I'm not sure why one parameter was labelled deviceWidth I just use the width of the Textview itself. Mine was match_parent and I suppose any TextView with wrap_content may not work at all. But that's what you get.
public static int getHeight(TextView t) {
int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(screenWidth(t.getContext()), View.MeasureSpec.AT_MOST);
int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
t.measure(widthMeasureSpec, heightMeasureSpec);
return t.getMeasuredHeight();
}
public static int screenWidth(Context context)
{
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
return display.getWidth();
}

Here is my easy solution its get the size before be painted
https://stackoverflow.com/a/40133275/1240672

Get line of TextView before rendering
This is my code base on idea above. It's working for me.
private int widthMeasureSpec;
private int heightMeasureSpec;
private int heightOfEachLine;
private int paddingFirstLine;
private void calculateHeightOfEachLine() {
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int deviceWidth = size.x;
widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(deviceWidth, View.MeasureSpec.AT_MOST);
heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
//1 line = 76; 2 lines = 76 + 66; 3 lines = 76 + 66 + 66
//=> height of first line = 76 pixel; height of second line = third line =... n line = 66 pixel
int heightOfFirstLine = getHeightOfTextView("A");
int heightOfSecondLine = getHeightOfTextView("A\nA") - heightOfFirstLine;
paddingFirstLine = heightOfFirstLine - heightOfSecondLine;
heightOfEachLine = heightOfSecondLine;
}
private int getHeightOfTextView(String text) {
// Getting height of text view before rendering to layout
TextView textView = new TextView(context);
textView.setPadding(10, 0, 10, 0);
//textView.setTypeface(typeface);
textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, context.getResources().getDimension(R.dimen.tv_size_14sp));
textView.setText(text, TextView.BufferType.SPANNABLE);
textView.measure(widthMeasureSpec, heightMeasureSpec);
return textView.getMeasuredHeight();
}
private int getLineCountOfTextViewBeforeRendering(String text) {
return (getHeightOfTextView(text) - paddingFirstLine) / heightOfEachLine;
}
Note: This code also must be set for real textview on screen
textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, context.getResources().getDimension(R.dimen.tv_size_14sp));

Kotlin extension
fun TextView.calculateHeight(text: CharSequence = getText()): Int {
val alignment = when(gravity) {
Gravity.CENTER -> Layout.Alignment.ALIGN_CENTER
Gravity.RIGHT -> Layout.Alignment.ALIGN_OPPOSITE
else -> Layout.Alignment.ALIGN_NORMAL
}
return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
StaticLayout.Builder.obtain(text, 0, text.length, TextPaint(paint), width)
.setLineSpacing(lineSpacingExtra, lineSpacingMultiplier)
.setAlignment(alignment)
.setIncludePad(true).build()
} else {
#Suppress("DEPRECATION")
StaticLayout(
text, TextPaint(paint), width, alignment,
lineSpacingMultiplier, lineSpacingExtra, true
)
}.height
}

Moving a view around the screen

I have an imageview that moves around the screen. So, I've set the LayoutParams to do it. But, the android insists on resize my imageview. How can I prevent this behavior?
public void move(int x, int y)
{
width = this.getWidth();
height = this.getHeight();
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(WIDTH, HEIGHT);
int t = validateMin(calcTopPos(y));
int l = validateMin(calcLeftPos(x));
int r = validateMaxWidth(calcRightPos(x))-1;
int b = validateMaxHeight(calcBottomPos(y));
params.setMargins(l, t, r, b);
this.setLayoutParams(params);
requestLayout();
}

I've found the answer: android:adjustViewBounds = "true" in the xml file. But, I still don't know why android was resizing my view. It's a mystery!

Why does getWidth() is larger than getLayoutParams().width sometimes?

My code for fixing ImageView:
private void fixImageWidth() {
int parentHeight = getHeight();
if (parentHeight == 0 || getParent() == null)
return;
Drawable drawable = image.getDrawable();
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) image.getLayoutParams();
if (drawable != null) {
int height = drawable.getIntrinsicHeight();
int width = drawable.getIntrinsicWidth();
lp.width = (int) ((float)(parentHeight - lp.topMargin * 2) / height * width);
} else {
lp.width = LayoutParams.WRAP_CONTENT;
}
image.requestLayout();
}
But sometimes actually image bounds is not changed. Below you could see HierarchyViewer properties of that object:
EDIT:
After I lot for debugging I determined, sometimes requestLayout don't remeasure image view. How does this happens?
EDIT:
I found solution, but still don't know reason. Solution is below:
image.post(new Runnable() {
#Override
public void run() {
image.requestLayout();
}
});
Any ideas?

Because getWidth() and getLayoutParams().width are different things. 1st relates to the View, the second is a layout request to the parent. If the parent cannot match the request the View maybe laid out with a different width. In this case you have requested MATCH_PARENT in the layout height and since an ImageView has a default scaleType of FIT_CENTER therefore content aspect ratio is maintained so the width will change.

How I can increase or decrease the size of an ImageView?

I would like to know how to enlarge an image that is already in the ImageView.
I have this:
m_imageView.setImageBitmap(imagen);
int newHeight = getWindowManager().getDefaultDisplay().getHeight() / 2;
int orgWidth = m_imageView.getDrawable().getIntrinsicWidth();
int orgHeight = m_imageView.getDrawable().getIntrinsicWidth();
int newWidth = (int) Math.floor((orgWidth * newHeight) / orgHeight);
//Use RelativeLayout.LayoutParams if your parent is a RelativeLayout
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
newWidth, newHeight);
m_imageView.setLayoutParams(params);
//m_imageView.setScaleType(ImageView.ScaleType.FIT_START);
But it does nothing, the image remains the same.
Thank you for your help.

did you invalidate the view? with invalidate() or postInvalidate() on your activity?

How to get the width and height of an Image View in android?

In my code I have an Image View in my XML layout and I keep changing the source image for this in my code. Now I want to know the width and height of the generated image each time.
I tried using getWidth(), getHeight(), getMeasuredWidth(), and getMeasuredHeight(), but they all return 0.
How can I get this?

Where you calling getWidth() and getHeight() on ImageView? If you calling from onCreate() in activity, it won't work. You need to wait for activity window to attached and then call getWidth() and getHeight() on ImageView. You can try calling getWidth() and getHeight() from onWindowFocusChanged() method of your activity.
#Override
public void onWindowFocusChanged(boolean hasFocus){
int width=imageView.getWidth();
int height=imageView.getHeight();
}

try this
ImageView iv=(ImageView)findViewById(R.id.image);
ViewTreeObserver vto = iv.getViewTreeObserver();
vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
finalHeight = iv.getMeasuredHeight();
finalWidth = iv.getMeasuredWidth();
Log.e("hilength","Height: " + finalHeight + " Width: " + finalWidth);
return true;
}
});

if you set ImageView a drawable, and the ImageView's height and width type is WRAP_CONTENT, you can get the ImageView's height and width by this even you calling from onCreate()
int height = imageView.getDrawable().getIntrinsicHeight();
int width = imageView.getDrawable().getIntrinsicWidth();

try this code
int finalHeight, finalWidth;
final ImageView iv = (ImageView)findViewById(R.id.scaled_image);
final TextView tv = (TextView)findViewById(R.id.size_label);
ViewTreeObserver vto = iv.getViewTreeObserver();
vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
iv.getViewTreeObserver().removeOnPreDrawListener(this);
finalHeight = iv.getMeasuredHeight();
finalWidth = iv.getMeasuredWidth();
tv.setText("Height: " + finalHeight + " Width: " + finalWidth);
return true;
}
});
it's really working...

The way you make reference to the image object is wrong. That's why you are given zero all the time. first create a bitmap object from imageview and get the width and height from it.
When taken a image from cam I do the following and it works like a charm.
Bitmap image2 = (Bitmap) data1.getExtras().get("data");
double width = Double.valueOf(image2.getWidth());
Log.v("WIDTH", String.valueOf(width));
double height = Double.valueOf(image2.getHeight());
Log.v("height", String.valueOf(height));
Hope it helps for you.

First you have to convert the image to mutablebitmap and the try to get the width and height of the image and mostly this will solve your issue..
Bitmap Rbitmap = Bitmap.createBitmap(bitmap).copy(
Config.ARGB_4444, true);
Rbitmap.getWidth();
Rbitmap.getheight();

Try this solution:
Bitmap bitmap = ((BitmapDrawable)imageView.getBackground()).getBitmap();
int width = bitmap.getWidth();
int height = bitmap.getHeight();

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