Skip to main content

Auto Scale TextView Text to Fit within Bounds ?

Auto Scale TextView Text to Fit within Bounds ?


A1. 

   

AppcompatTextView now supports auto sizing starting from Support Library 26.0. TextView in Android O also works same way.
<LinearLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      android:layout_width="match_parent"
      android:layout_height="wrap_content">

      <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:autoSizeTextType="uniform"
        app:autoSizeMinTextSize="12sp"
        app:autoSizeMaxTextSize="100sp"
        app:autoSizeStepGranularity="2sp"
      />

</LinearLayout>


A2.In Java

    public MyTextView extends TextView{

    public void resize(String text, float textViewWidth, float textViewHeight) {
       Paint p = new Paint();
       Rect bounds = new Rect();
       p.setTextSize(1);
       p.getTextBounds(text, 0, text.length(), bounds);
       float widthDifference = (textViewWidth)/bounds.width();
       float heightDifference = (textViewHeight);
       textSize = Math.min(widthDifference, heightDifference);
       setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
}


A3.

    Extend TextView and override onDraw with the code below. It will keep text aspect ratio but size it to fill the space. You could easily modify code to stretch if necessary.

  @Override
  protected void onDraw(@NonNull Canvas canvas) {
    TextPaint textPaint = getPaint();
    textPaint.setColor(getCurrentTextColor());
    textPaint.setTextAlign(Paint.Align.CENTER);
    textPaint.drawableState = getDrawableState();

    String text = getText().toString();
    float desiredWidth = getMeasuredWidth() - getPaddingLeft() - getPaddingRight() - 2;
    float desiredHeight = getMeasuredHeight() - getPaddingTop() - getPaddingBottom() - 2;
    float textSize = textPaint.getTextSize();

    for (int i = 0; i < 10; i++) {
      textPaint.getTextBounds(text, 0, text.length(), rect);
      float width = rect.width();
      float height = rect.height();

      float deltaWidth = width - desiredWidth;
      float deltaHeight = height - desiredHeight;

      boolean fitsWidth = deltaWidth <= 0;
      boolean fitsHeight = deltaHeight <= 0;

      if ((fitsWidth && Math.abs(deltaHeight) < 1.0)
          || (fitsHeight && Math.abs(deltaWidth) < 1.0)) {
        // close enough
        break;
      }

      float adjustX = desiredWidth / width;
      float adjustY = desiredHeight / height;

      textSize = textSize * (adjustY < adjustX ? adjustY : adjustX);

      // adjust text size
      textPaint.setTextSize(textSize);
    }
    float x = desiredWidth / 2f;
    float y = desiredHeight / 2f - rect.top - rect.height() / 2f;
    canvas.drawText(text, x, y, textPaint);
  }




















Comments

Popular posts from this blog

Reset Android textview maxlines ?

Reset Android textview maxlines  ? A1.         Actually, the way android platform does that is by setting the MaxLine to                                            Integer.MAX_VALUE. textView . setMaxLines ( Integer . MAX_VALUE );        also, if you are using Ellipsize, don't forget to set to null. textView . setEllipsize ( null );       just check how the android framework do just that ;) watch the                                                              setMaxLines(Integer.MAX_VALUE); private void applySingleLine ( boolean singleLine , boolean applyTransformation ) { mSingleLine = singleLine ; if ( singleLine ) { ...

Android set the gravity for a TextView programmatically

Android set the gravity for a TextView programmatically  A1.        This will center the text in a text view: TextView ta = ( TextView ) findViewById ( R . layout . text_view ); LayoutParams lp = new LayoutParams (); lp . gravity = Gravity . CENTER_HORIZONTAL ; ta . setLayoutParams ( lp ); A2.      textView . setGravity ( Gravity . CENTER | Gravity . BOTTOM ); A3.              Use this code TextView textView = new TextView ( YourActivity . this ); textView . setGravity ( Gravity . CENTER | Gravity . TOP ); textView . setText ( "some text

Android and   in TextView ?

Android and &nbsp; in TextView ? A1.            The TextView should respect the non breaking space <string name = "test" > Hello&#160;world </string>                                     or new TextView ( "Hello\u00A0world" ); A2.      One unique situation I ran into was adding a non-breaking space to a string resource that took               String.format parameters. <resources> <string name = "answer_progress" formatted = "false" > Answered %d of %d </string> </resources>       I tried to simply copy and past the non-breaking space character into the string and it was                     replaced       with a regular old space after compilin...