Android: Get Height of a View Before It's Drawn

Getting height of text view before rendering to layout

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();
}

Accurate way to determine the measured height of a view, even before it changed from GONE to VISIBLE

Your 2nd code snippet is almost correct, but you need to specify pixel sizes - not FILL_PARENT/MATCH_PARENT. This should work:

v.measure(MeasureSpec.makeMeasureSpec(parentView.getWidth(), MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(MAX_HEIGHT, MeasureSpec.AT_MOST));
final int targetHeight = v.getMeasuredHeight();

You'll need to have a reference to the ViewGroup that v is a child of to get its width, and define MAX_HEIGHT (or perhaps use the parent View's height?).

Also, you should change the height parameters of the two TextViews that are within the horizontal LinearLayout to wrap_content, as using match_parent here may cause problems. The LinearLayout is set to wrap_content, but the two children don't specify a height.

How to correctly measure the height of a view before it is drawn

Try the following observer

{
ViewTreeObserver treeObserver=measuringView.getViewTreeObserver();
treeObserver.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {

@Override
public void onGlobalLayout() {
int height=measuringView.getHeight();
}
}
}

View's getWidth() and getHeight() returns 0

You are calling getWidth() too early. The UI has not been sized and laid out on the screen yet.

I doubt you want to be doing what you are doing, anyway -- widgets being animated do not change their clickable areas, and so the button will still respond to clicks in the original orientation regardless of how it has rotated.

That being said, you can use a dimension resource to define the button size, then reference that dimension resource from your layout file and your source code, to avoid this problem.



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