how to show string depending upon width of the layout - android

I have created two layout vertically of equal width. And I have string data to be displayed on text view dynamically. When string is greater than the width of the layout then string is wrapped to the width of the layout and for remaining string I want to create a new TV dynamically. This process ends till remaining string finishes. For next string same process continues. When the process reaches bottom of linearlayout1, remaining string should starts from linearlayout2. And the process continues till it reaches bottom of linearlayout2.
I tried like this
private void nextlinechar(int numChars,String devstr) {
nextchar=devstr;
Log.d("char 1",""+nextchar);
TextView sub=new TextView(getApplicationContext());
sub.setLines(1);
sub.setTextColor(Color.BLACK);
sub.setTextSize(textsize);
sub.setText(nextchar);
nextchar=devstr.substring(nextcharstart);
String textToBeSplit = nextchar; // Text you want to split between TextViews
String data=TextMeasure(nextchar,sub);
float myTextSize=sub.getTextSize();
float textView2Width=400;
// String next=TextMeasure(nextchar,sub);
Paint paint = new Paint();
paint.setTextSize(myTextSize); // Your text size
numChars1= paint.breakText(textToBeSplit, true,textView2Width, null);
nextchar1=nextchar.substring(numChars1);
// Log.d("char",""+i+" "+nextchar.length());
main.addView(sub);
nextlinechar(numChars1,nextchar);
}
Illustration

Possible Solution 1
What you need is a FlowLayout, found here. Basically the text needs to wrap around, instead of overflow to the right.
Possible Solution 2
Try to use a webview instead, and populate the text in 2 webviews. That will be faster with lesser code and not as buggy.
I used FlowLayout only when I needed to click on each word separately. Basically a test for grammar where people select the Parts Of Speech of the sentence. For that I needed listener on each word.

Reffer This may be this help you:
package com.example.demo;
import android.content.Context;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.widget.TextView;
public class FontFitTextView extends TextView {
public FontFitTextView(Context context) {
super(context);
initialise();
}
public FontFitTextView(Context context, AttributeSet attrs) {
super(context, attrs);
initialise();
}
private void initialise() {
mTestPaint = new Paint();
mTestPaint.set(this.getPaint());
// max size defaults to the initially specified text size unless it is
// too small
}
/*
* Re size the font so the specified text fits in the text box assuming the
* text box is the specified width.
*/
private void refitText(String text, int textWidth) {
if (textWidth <= 0)
return;
int targetWidth = textWidth - this.getPaddingLeft()
- this.getPaddingRight();
float hi = 100;
float lo = 2;
final float threshold = 0.5f; // How close we have to be
mTestPaint.set(this.getPaint());
while ((hi - lo) > threshold) {
float size = (hi + lo) / 2;
mTestPaint.setTextSize(size);
if (mTestPaint.measureText(text) >= targetWidth)
hi = size; // too big
else
lo = size; // too small
}
// Use lo so that we undershoot rather than overshoot
this.setTextSize(TypedValue.COMPLEX_UNIT_PX, lo);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int parentWidth = MeasureSpec.getSize(widthMeasureSpec);
int height = getMeasuredHeight();
refitText(this.getText().toString(), parentWidth);
this.setMeasuredDimension(parentWidth, height);
}
#Override
protected void onTextChanged(final CharSequence text, final int start,
final int before, final int after) {
refitText(text.toString(), this.getWidth());
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
if (w != oldw) {
refitText(this.getText().toString(), w);
}
}
// Attributes
private Paint mTestPaint;
}

The following is an idea I came up with (of course I first tried to search for a built-in method of TextViwe which does what you need, but couldn't find any):
Determine how many lines should be displayed in each of the layouts (left and right) depending on the screen size (this.getResources().getDefaultDisplay() and then search for the right method), the desired text size and the spaces between the layouts and between the text and the top/bottom edges. Don't forget you may need to convert pixels to dips or vice versa, as most Android size measure methods return size in pixels.
Set the max number of lines to each of the TVs (tv.setLines()).
Set the entire text to the left TV.
Now the first half of the text will be displayed in the left TV. The other part of the text will be hidden because you've reached the max num of lines in the TV. So, use getText() to receive the text currently displayed in the TV (hopefully, this will return only the first half of the text.. haven't tried that out yet, sorry. If not, maybe there's some getDisplayedText() method or something). Now you can use simple Java methods to retrieve only the remining part of the text from the original text (a substring) and set it to the second TV.
Hope that helps.

Related

how to change a soft keyboard's height at run-time?

I'm designing a soft keyboard and I want to change its height at run-time as the user choose between landscape and portrait mode. I know how to change key's height in xml, but I need to do it dynamically.
The only thing that came to my mind was to subclass from Keyboard and override its setKeysHeight (int height), but it seems useless as the whole keyboard stopped responding to my clicks and the height (though different from previously) didn't care about 'height' in the aforementioned function.
Any idea/workaround?
Original solution posted at https://stackoverflow.com/a/9695482/1241783 but it doesn't come with explanation so here I extend it a bit.
1) Create a new class that extends the Keyboard class that overrides the getHeight() method.
#Override
public int getHeight() {
return getKeyHeight() * 3;
}
Note: the number 3 here is your total number of rows, if your keyboard has 5 rows, put 5.
If your keyboard row height is different for each row, here you need to calculate yourself and return the total height (unit is in pixels, took me a while to figure out that it is not dp so need to convert dp to pixel for all calculations) for example:
#Override
public int getHeight() {
return row1Height + row2Height + row3Height + row4Height + row5Height;
}
2) Create a new public function in the same class.
public void changeKeyHeight(double height_modifier)
{
int height = 0;
for(Keyboard.Key key : getKeys()) {
key.height *= height_modifier;
key.y *= height_modifier;
height = key.height;
}
setKeyHeight(height);
getNearestKeys(0, 0); //somehow adding this fixed a weird bug where bottom row keys could not be pressed if keyboard height is too tall.. from the Keyboard source code seems like calling this will recalculate some values used in keypress detection calculation
}
If you're not using height_modifier but set to specific height instead, you'll need to calculate key.y position yourself.
If your keyboard row height is different for each row, you may need to check the keys, determine the row it belongs and set the height to correct value if not the keys will overlap each other. Also store the row heights in private variable to be used in getHeight() above. PS: On certain configuration I couldn't press the bottom row keys after changing keyboard height, and I found that calling getNearestKeys() fixes that though I'm not exactly sure why.
Note: key.y is y position of the key, coordinate 0 starts from the top of the keyboard, and goes down as the value increases. e.g. Coordinate 100 points to 100 pixel from the top of the keyboard :)
3) Last step is to call changeKeyHeight in your main class that extends InputMethodService. Do it inside (override it) onStartInputView() as this is where the keyboard should be redrawn after you change the height (via preference or something).
If you're looking at the Android soft keyboard sample project, it will be like this:
#Override public void onStartInputView(EditorInfo attribute, boolean restarting) {
super.onStartInputView(attribute, restarting);
// Change the key height here dynamically after getting your value from shared preference or something
mCurKeyboard.changeKeyHeight(1.5);
// Apply the selected keyboard to the input view.
mInputView.setKeyboard(mCurKeyboard);
mInputView.closing();
final InputMethodSubtype subtype = mInputMethodManager.getCurrentInputMethodSubtype();
mInputView.setSubtypeOnSpaceKey(subtype);
}
Cheers!
Extra: If you need a dp to pixel converter, here's the code:
private int convertDpToPx(int dp)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, getResources().getDisplayMetrics());
}
I use the following code with Android 6:
private void adjustKeyboardKeyHeight (MyKeyboard keyboard, int newKeyHeight) {
int oldKeyHeight = keyboard.getKeyHeight();
int verticalGap = keyboard.getVerticalGap();
int rows = 0;
for (Keyboard.Key key : keyboard.getKeys()) {
key.height = newKeyHeight;
int row = (key.y + verticalGap) / (oldKeyHeight + verticalGap);
key.y = row * newKeyHeight + (row - 1) * verticalGap;
rows = Math.max(rows, row + 1);
}
keyboard.setHeight(rows * newKeyHeight + (rows - 1) * verticalGap);
}
private static class MyKeyboard extends Keyboard {
private int height;
MyKeyboard (Context context, int xmlLayoutResId) {
super(context, xmlLayoutResId);
height = super.getHeight();
}
#Override public int getKeyHeight() {
return super.getKeyHeight();
}
#Override public int getVerticalGap() {
return super.getVerticalGap();
}
public void setHeight (int newHeight) {
height = newHeight;
}
#Override public int getHeight() {
return height;
}
}
Bruce's solution does not work anymore. Bottom keys stop responding after resize. Look at Keyboard.java:
public int[] getNearestKeys(int x, int y) {
if (mGridNeighbors == null) computeNearestNeighbors();
So getNearestKeys does not trigger any computations, computeNearestNeighbors() is not called more than once (and it's private, so you can't call it directly).
Instead of changing size in existing object, I modified Keyboard.Key class:
public class FTKey extends Keyboard.Key {
FTKey(Resources res, Keyboard.Row parent, int x, int y, XmlResourceParser parser) {
super(res, parent, x, y, parser);
this.height = (int) (height * FTPref.yScale);
this.y = this.height * FTPref.yScale; // This works only if all rows of the same height
}
In onStartInput() I re-create all keyboard objects anew every time:
FTPref.yScale = 0.7f;
mEnglishKeyboard = new FTKeyboard(this ...
mRussianKeyboard = new FTKeyboard(this ...
Overriding getHeight() to calculate total keyboard height is still required.
It will be tricky to have keys of different height, because you'll have to calculate not only total height, but y position of every button and it depends on the height of previous rows.

Android Spannable Line Height

I have been trying to figure this one out for the last couple of days now, and have had no success...
I'm learning android right now, and am currently creating a calculator with history as my learning project. I have a TextView that is responsible for displaying all history... I'm using a digital font that looks like a calculator font, but this only looks good for digits and decimals and comma's. I want all operators to be highlighted and in a different font (Arial Narrow at the moment). I have been able to get this to work beautifully using a spannable string where I'm specifying a font color as well as a font using a CustomTypeFaceSpan class to apply my custom fonts.
The problem... When I mix the Typefaces, there seems to be an issue with the line height, so I found this post which demonstrates using another custom defined class to apply a line height to each added line of spannable text:
public class CustomLineHeightSpan implements LineHeightSpan{
private final int height;
public CustomLineHeightSpan(int height){
this.height = height;
}
#Override
public void chooseHeight(CharSequence text, int start, int end, int spanstartv, int v, FontMetricsInt fm) {
fm.bottom += height;
fm.descent += height;
}
}
This does not seem to work, and I can not figure out why. If I don't apply the different typefaces, then it displays as expected with no space above the first line, and about 5px spacing between lines. When I apply the alternate typefaces, there is a space of about 10 to 15px above the first line of text and the line spacing is about the same 10 to 15px.
There is no difference in the font size, only the typeface. What am I missing. I implemented the CustomLineHeightSpan which implements LineHeightSpan and overrides the chooseHeight method. I call it like so:
WordtoSpan.setSpan(new CustomLineHeightSpan(10), operatorPositions.get(ii), operatorPositions.get(ii) + 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
It does not seem to matter what I put in the call to CustomLineHeightSpan. Nothing changes...
Anybody have any idea what I'm missing... I'm sure it's an "I can't believe I missed that" answer, but can't seem to figure it out at the moment.
Thanks for the help guys :-)
I finally found a more in depth example of the use of LineHeightSpan... Actually LineHeightSpan.WithDensity to be more precise... The following is the excerpt that helped me to resolve my issue:
private static class Height implements LineHeightSpan.WithDensity {
private int mSize;
private static float sProportion = 0;
public Height(int size) {
mSize = size;
}
public void chooseHeight(CharSequence text, int start, int end,
int spanstartv, int v,
Paint.FontMetricsInt fm) {
// Should not get called, at least not by StaticLayout.
chooseHeight(text, start, end, spanstartv, v, fm, null);
}
public void chooseHeight(CharSequence text, int start, int end,
int spanstartv, int v,
Paint.FontMetricsInt fm, TextPaint paint) {
int size = mSize;
if (paint != null) {
size *= paint.density;
}
if (fm.bottom - fm.top < size) {
fm.top = fm.bottom - size;
fm.ascent = fm.ascent - size;
} else {
if (sProportion == 0) {
/*
* Calculate what fraction of the nominal ascent
* the height of a capital letter actually is,
* so that we won't reduce the ascent to less than
* that unless we absolutely have to.
*/
Paint p = new Paint();
p.setTextSize(100);
Rect r = new Rect();
p.getTextBounds("ABCDEFG", 0, 7, r);
sProportion = (r.top) / p.ascent();
}
int need = (int) Math.ceil(-fm.top * sProportion);
if (size - fm.descent >= need) {
/*
* It is safe to shrink the ascent this much.
*/
fm.top = fm.bottom - size;
fm.ascent = fm.descent - size;
} else if (size >= need) {
/*
* We can't show all the descent, but we can at least
* show all the ascent.
*/
fm.top = fm.ascent = -need;
fm.bottom = fm.descent = fm.top + size;
} else {
/*
* Show as much of the ascent as we can, and no descent.
*/
fm.top = fm.ascent = -size;
fm.bottom = fm.descent = 0;
}
}
}
}
This was taken from this example.
What it does is as quoted below:
Forces the text line to be the specified height, shrinking/stretching
the ascent if possible, or the descent if shrinking the ascent further
will make the text unreadable.
I hope this helps the next person :-)

Android font size not scaling on tablet [duplicate]

I'm trying to create a method for resizing multi-line text in a TextView such that it fits within the bounds (both the X and Y dimensions) of the TextView.
At present, I have something, but all it does is resize the text such that just the first letter/character of the text fills the dimensions of the TextView (i.e. only the first letter is viewable, and it's huge). I need it to fit all the lines of the text within the bounds of the TextView.
Here is what I have so far:
public static void autoScaleTextViewTextToHeight(TextView tv)
{
final float initSize = tv.getTextSize();
//get the width of the view's back image (unscaled)....
float minViewHeight;
if(tv.getBackground()!=null)
{
minViewHeight = tv.getBackground().getIntrinsicHeight();
}
else
{
minViewHeight = 10f;//some min.
}
final float maxViewHeight = tv.getHeight() - (tv.getPaddingBottom()+tv.getPaddingTop())-12;// -12 just to be sure
final String s = tv.getText().toString();
//System.out.println(""+tv.getPaddingTop()+"/"+tv.getPaddingBottom());
if(minViewHeight >0 && maxViewHeight >2)
{
Rect currentBounds = new Rect();
tv.getPaint().getTextBounds(s, 0, s.length(), currentBounds);
//System.out.println(""+initSize);
//System.out.println(""+maxViewHeight);
//System.out.println(""+(currentBounds.height()));
float resultingSize = 1;
while(currentBounds.height() < maxViewHeight)
{
resultingSize ++;
tv.setTextSize(resultingSize);
tv.getPaint().getTextBounds(s, 0, s.length(), currentBounds);
//System.out.println(""+(currentBounds.height()+tv.getPaddingBottom()+tv.getPaddingTop()));
//System.out.println("Resulting: "+resultingSize);
}
if(currentBounds.height()>=maxViewHeight)
{
//just to be sure, reduce the value
tv.setTextSize(resultingSize-1);
}
}
}
I think the problem is in the use of tv.getPaint().getTextBounds(...). It always returns small numbers for the text bounds... small relative to the tv.getWidth() and tv.getHeight() values... even if the text size is far larger than the width or height of the TextView.
The AutofitTextView library from MavenCentral handles this nicely. The source hosted on Github(1k+ stars) at https://github.com/grantland/android-autofittextview
Add the following to your app/build.gradle
repositories {
mavenCentral()
}
dependencies {
implementation 'me.grantland:autofittextview:0.2.+'
}
Enable any View extending TextView in code:
AutofitHelper.create(textView);
Enable any View extending TextView in XML:
<me.grantland.widget.AutofitLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:singleLine="true"
/>
</me.grantland.widget.AutofitLayout>
Use the built in Widget in code or XML:
<me.grantland.widget.AutofitTextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:singleLine="true"
/>
New since Android O:
https://developer.android.com/preview/features/autosizing-textview.html
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:autoSizeTextType="uniform"
android:autoSizeMinTextSize="12sp"
android:autoSizeMaxTextSize="100sp"
android:autoSizeStepGranularity="2sp"
/>
I have played with this for quite some time, trying to get my font sizes correct on a wide variety of 7" tablets (kindle fire, Nexus7, and some inexpensive ones in China with low-res screens) and devices.
The approach that finally worked for me is as follows. The "32" is an arbitrary factor that basically gives about 70+ characters across a 7" tablet horizontal line, which is a font size I was looking for. Adjust accordingly.
textView.setTextSize(getFontSize(activity));
public static int getFontSize (Activity activity) {
DisplayMetrics dMetrics = new DisplayMetrics();
activity.getWindowManager().getDefaultDisplay().getMetrics(dMetrics);
// lets try to get them back a font size realtive to the pixel width of the screen
final float WIDE = activity.getResources().getDisplayMetrics().widthPixels;
int valueWide = (int)(WIDE / 32.0f / (dMetrics.scaledDensity));
return valueWide;
}
I was able to answer my own question using the following code (see below), but my solution was very specific to the application. For instance, this will probably only look good and/or work for a TextView sized to approx. 1/2 the screen (with also a 40px top margin and 20px side margins... no bottom margin).
The using this approach though, you can create your own similar implementation. The static method basically just looks at the number of characters and determines a scaling factor to apply to the TextView's text size, and then incrementally increases the text size until the overall height (an estimated height -- using the width of the text, the text height, and the width of the TextView) is just below that of the TextView. The parameters necessary to determine the scaling factor (i.e. the if/else if statements) were set by guess-and-check. You'll likely have to play around with the numbers to make it work for your particular application.
This isn't the most elegant solution, though it was easy to code and it works for me. Does anyone have a better approach?
public static void autoScaleTextViewTextToHeight(final TextView tv, String s)
{
float currentWidth=tv.getPaint().measureText(s);
int scalingFactor = 0;
final int characters = s.length();
//scale based on # of characters in the string
if(characters<5)
{
scalingFactor = 1;
}
else if(characters>=5 && characters<10)
{
scalingFactor = 2;
}
else if(characters>=10 && characters<15)
{
scalingFactor = 3;
}
else if(characters>=15 && characters<20)
{
scalingFactor = 3;
}
else if(characters>=20 && characters<25)
{
scalingFactor = 3;
}
else if(characters>=25 && characters<30)
{
scalingFactor = 3;
}
else if(characters>=30 && characters<35)
{
scalingFactor = 3;
}
else if(characters>=35 && characters<40)
{
scalingFactor = 3;
}
else if(characters>=40 && characters<45)
{
scalingFactor = 3;
}
else if(characters>=45 && characters<50)
{
scalingFactor = 3;
}
else if(characters>=50 && characters<55)
{
scalingFactor = 3;
}
else if(characters>=55 && characters<60)
{
scalingFactor = 3;
}
else if(characters>=60 && characters<65)
{
scalingFactor = 3;
}
else if(characters>=65 && characters<70)
{
scalingFactor = 3;
}
else if(characters>=70 && characters<75)
{
scalingFactor = 3;
}
else if(characters>=75)
{
scalingFactor = 5;
}
//System.out.println(((int)Math.ceil(currentWidth)/tv.getWidth()+scalingFactor));
//the +scalingFactor is important... increase this if nec. later
while((((int)Math.ceil(currentWidth)/tv.getWidth()+scalingFactor)*tv.getTextSize())<tv.getHeight())
{
tv.setTextSize(TypedValue.COMPLEX_UNIT_SP, tv.getTextSize()+0.25f);
currentWidth=tv.getPaint().measureText(s);
//System.out.println(((int)Math.ceil(currentWidth)/tv.getWidth()+scalingFactor));
}
tv.setText(s);
}
Thanks.
I had the same problem and wrote a class that seems to work for me. Basically, I used a static layout to draw the text in a separate canvas and remeasure until I find a font size that fits. You can see the class posted in the topic below. I hope it helps.
Auto Scale TextView Text to Fit within Bounds
Stumbled upon this whilst looking for a solution myself... I'd tried all the other solutions out there that I could see on stack overflow etc but none really worked so I wrote my own.
Basically by wrapping the text view in a custom linear layout I've been able to successfully measure the text properly by ensuring it is measured with a fixed width.
<!-- TextView wrapped in the custom LinearLayout that expects one child TextView -->
<!-- This view should specify the size you would want the text view to be displayed at -->
<com.custom.ResizeView
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_margin="10dp"
android:layout_weight="1"
android:orientation="horizontal" >
<TextView
android:id="#+id/CustomTextView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
</com.custom.ResizeView>
Then the linear layout code
public class ResizeView extends LinearLayout {
public ResizeView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public ResizeView(Context context) {
super(context);
}
#Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
// oldWidth used as a fixed width when measuring the size of the text
// view at different font sizes
final int oldWidth = getMeasuredWidth() - getPaddingBottom() - getPaddingTop();
final int oldHeight = getMeasuredHeight() - getPaddingLeft() - getPaddingRight();
// Assume we only have one child and it is the text view to scale
TextView textView = (TextView) getChildAt(0);
// This is the maximum font size... we iterate down from this
// I've specified the sizes in pixels, but sp can be used, just modify
// the call to setTextSize
float size = getResources().getDimensionPixelSize(R.dimen.solutions_view_max_font_size);
for (int textViewHeight = Integer.MAX_VALUE; textViewHeight > oldHeight; size -= 0.1f) {
textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, size);
// measure the text views size using a fixed width and an
// unspecified height - the unspecified height means measure
// returns the textviews ideal height
textView.measure(MeasureSpec.makeMeasureSpec(oldWidth, MeasureSpec.EXACTLY), MeasureSpec.UNSPECIFIED);
textViewHeight = textView.getMeasuredHeight();
}
}
}
Hope this helps someone.
maybe try setting setHoriztonallyScrolling() to true before taking text measurements so that the textView doesn't try to layout your text on multiple lines
One way would be to specify different sp dimensions for each of the generalized screen sizes. For instance, provide 8sp for small screens, 12sp for normal screens, 16 sp for large and 20 sp for xlarge. Then just have your layouts refer to #dimen text_size or whatever and you can rest assured, as density is taken care of via the sp unit. See the following link for more info on this approach.
http://www.developer.android.com/guide/topics/resources/more-resources.html#Dimension
I must note, however, that supporting more languages means more work during the testing phase, especially if you're interested in keeping text on one line, as some languages have much longer words. In that case, make a dimens.xml file in the values-de-large folder, for example, and tweak the value manually. Hope this helps.
Here is a solution that I created based on some other feedback. This solution allows you to set the size of the text in XML which will be the max size and it will adjust itself to fit the view height.
Size Adjusting TextView
private float findNewTextSize(int width, int height, CharSequence text) {
TextPaint textPaint = new TextPaint(getPaint());
float targetTextSize = textPaint.getTextSize();
int textHeight = getTextHeight(text, textPaint, width, targetTextSize);
while(textHeight > height && targetTextSize > mMinTextSize) {
targetTextSize = Math.max(targetTextSize - 1, mMinTextSize);
textHeight = getTextHeight(text, textPaint, width, targetTextSize);
}
return targetTextSize;
}
private int getTextHeight(CharSequence source, TextPaint paint, int width, float textSize) {
paint.setTextSize(textSize);
StaticLayout layout = new StaticLayout(source, paint, width, Alignment.ALIGN_NORMAL, mSpacingMult, mSpacingAdd, true);
return layout.getHeight();
}
If your only requirement is to have the text automatically split and continue in the next line and the height is not important then just have it like this.
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:maxEms="integer"
android:width="integer"/>
This will have your TextView wrap to it's content vertically depending on your maxEms value.
Check if my solution helps you:
Auto Scale TextView Text to Fit within Bounds
I found that this worked well for me. see: https://play.google.com/store/apps/details?id=au.id.rupert.chauffeurs_name_board&hl=en
Source Code at http://www.rupert.id.au/chauffeurs_name_board/verson2.php
http://catchthecows.com/?p=72 and https://github.com/catchthecows/BigTextButton
This is based on mattmook's answer. It worked well on some devices, but not on all. I moved the resizing to the measuring step, made the maximum font size a custom attribute, took margins into account, and extended FrameLayout instead of LineairLayout.
public class ResizeView extends FrameLayout {
protected float max_font_size;
public ResizeView(Context context, AttributeSet attrs) {
super(context, attrs);
TypedArray a = context.getTheme().obtainStyledAttributes(
attrs,
R.styleable.ResizeView,
0, 0);
max_font_size = a.getDimension(R.styleable.ResizeView_maxFontSize, 30.0f);
}
public ResizeView(Context context) {
super(context);
}
#Override
protected void onMeasure(final int widthMeasureSpec, final int heightMeasureSpec) {
// Use the parent's code for the first measure
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
// Assume we only have one child and it is the text view to scale
final TextView textView = (TextView) getChildAt(0);
// Check if the default measure resulted in a fitting textView
LayoutParams childLayout = (LayoutParams) textView.getLayoutParams();
final int textHeightAvailable = getMeasuredHeight() - getPaddingTop() - getPaddingBottom() - childLayout.topMargin - childLayout.bottomMargin;
int textViewHeight = textView.getMeasuredHeight();
if (textViewHeight < textHeightAvailable) {
return;
}
final int textWidthSpec = MeasureSpec.makeMeasureSpec(
MeasureSpec.getSize(widthMeasureSpec) - getPaddingLeft() - getPaddingRight() - childLayout.leftMargin - childLayout.rightMargin,
MeasureSpec.EXACTLY);
final int textHeightSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
for (float size = max_font_size; size >= 1.05f; size-=0.1f) {
textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, size);
textView.measure(textWidthSpec, textHeightSpec);
textViewHeight = textView.getMeasuredHeight();
if (textViewHeight <= textHeightAvailable) {
break;
}
}
}
}
And this in attrs.xml:
<declare-styleable name="ResizeView">
<attr name="maxFontSize" format="reference|dimension"/>
</declare-styleable>
And finally used like this:
<PACKAGE_NAME.ui.ResizeView xmlns:custom="http://schemas.android.com/apk/res/PACKAGE_NAME"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="start|center_vertical"
android:padding="5dp"
custom:maxFontSize="#dimen/normal_text">
<TextView android:id="#+id/tabTitle2"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</PACKAGE_NAME.ui.ResizeView>
Try this...
tv.setText("Give a very large text anc check , this xample is very usefull");
countLine=tv.getLineHeight();
System.out.println("LineCount " + countLine);
if (countLine>=40){
tv.setTextSize(15);
}

Measuring text height to be drawn on Canvas ( Android )

Any straight forward way to measure the height of text?
The way I am doing it now is by using Paint's measureText() to get the width, then by trial and error finding a value to get an approximate height. I've also been messing around with FontMetrics, but all these seem like approximate methods that suck.
I am trying to scale things for different resolutions. I can do it, but I end up with incredibly verbose code with lots of calculations to determine relative sizes. I hate it! There has to be a better way.
There are different ways to measure the height depending on what you need.
#1 getTextBounds
If you are doing something like precisely centering a small amount of fixed text, you probably want getTextBounds. You can get the bounding rectangle like this
Rect bounds = new Rect();
mTextPaint.getTextBounds(mText, 0, mText.length(), bounds);
int height = bounds.height();
As you can see for the following images, different strings will give different heights (shown in red).
These differing heights could be a disadvantage in some situations when you just need a constant height no matter what the text is. See the next section.
#2 Paint.FontMetrics
You can calculate the hight of the font from the font metrics. The height is always the same because it is obtained from the font, not any particular text string.
Paint.FontMetrics fm = mTextPaint.getFontMetrics();
float height = fm.descent - fm.ascent;
The baseline is the line that the text sits on. The descent is generally the furthest a character will go below the line and the ascent is generally the furthest a character will go above the line. To get the height you have to subtract ascent because it is a negative value. (The baseline is y=0 and y descreases up the screen.)
Look at the following image. The heights for both of the strings are 234.375.
If you want the line height rather than just the text height, you could do the following:
float height = fm.bottom - fm.top + fm.leading; // 265.4297
These are the bottom and top of the line. The leading (interline spacing) is usually zero, but you should add it anyway.
The images above come from this project. You can play around with it to see how Font Metrics work.
#3 StaticLayout
For measuring the height of multi-line text you should use a StaticLayout. I talked about it in some detail in this answer, but the basic way to get this height is like this:
String text = "This is some text. This is some text. This is some text. This is some text. This is some text. This is some text.";
TextPaint myTextPaint = new TextPaint();
myTextPaint.setAntiAlias(true);
myTextPaint.setTextSize(16 * getResources().getDisplayMetrics().density);
myTextPaint.setColor(0xFF000000);
int width = 200;
Layout.Alignment alignment = Layout.Alignment.ALIGN_NORMAL;
float spacingMultiplier = 1;
float spacingAddition = 0;
boolean includePadding = false;
StaticLayout myStaticLayout = new StaticLayout(text, myTextPaint, width, alignment, spacingMultiplier, spacingAddition, includePadding);
float height = myStaticLayout.getHeight();
What about paint.getTextBounds() (object method)
#bramp's answer is correct - partially, in that it does not mention that the calculated boundaries will be the minimum rectangle that contains the text fully with implicit start coordinates of 0, 0.
This means, that the height of, for example "Py" will be different from the height of "py" or "hi" or "oi" or "aw" because pixel-wise they require different heights.
This by no means is an equivalent to FontMetrics in classic java.
While width of a text is not much of a pain, height is.
In particular, if you need to vertically center-align the drawn text, try getting the boundaries of the text "a" (without quotes), instead of using the text you intend to draw.
Works for me...
Here's what I mean:
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.LINEAR_TEXT_FLAG);
paint.setStyle(Paint.Style.FILL);
paint.setColor(color);
paint.setTextAlign(Paint.Align.CENTER);
paint.setTextSize(textSize);
Rect bounds = new Rect();
paint.getTextBounds("a", 0, 1, bounds);
buffer.drawText(this.myText, canvasWidth >> 1, (canvasHeight + bounds.height()) >> 1, paint);
// remember x >> 1 is equivalent to x / 2, but works much much faster
Vertically center aligning the text means vertically center align the bounding rectangle - which is different for different texts (caps, long letters etc). But what we actually want to do is to also align the baselines of rendered texts, such that they did not appear elevated or grooved. So, as long as we know the center of the smallest letter ("a" for example) we then can reuse its alignment for the rest of the texts. This will center align all the texts as well as baseline-align them.
The height is the text size you have set on the Paint variable.
Another way to find out the height is
mPaint.getTextSize();
You could use the android.text.StaticLayout class to specify the bounds required and then call getHeight(). You can draw the text (contained in the layout) by calling its draw(Canvas) method.
You can simply get the text size for a Paint object using getTextSize() method.
For example:
Paint mTextPaint = new Paint (Paint.ANTI_ALIAS_FLAG);
//use densityMultiplier to take into account different pixel densities
final float densityMultiplier = getContext().getResources()
.getDisplayMetrics().density;
mTextPaint.setTextSize(24.0f*densityMultiplier);
//...
float size = mTextPaint.getTextSize();
You must use Rect.width() and Rect.Height() which returned from getTextBounds() instead. That works for me.
If anyone still has problem, this is my code.
I have a custom view which is square (width = height) and I want to assign a character to it. onDraw() shows how to get height of character, although I'm not using it. Character will be displayed in the middle of view.
public class SideBarPointer extends View {
private static final String TAG = "SideBarPointer";
private Context context;
private String label = "";
private int width;
private int height;
public SideBarPointer(Context context) {
super(context);
this.context = context;
init();
}
public SideBarPointer(Context context, AttributeSet attrs) {
super(context, attrs);
this.context = context;
init();
}
public SideBarPointer(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
this.context = context;
init();
}
private void init() {
// setBackgroundColor(0x64FF0000);
}
#Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec){
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
height = this.getMeasuredHeight();
width = this.getMeasuredWidth();
setMeasuredDimension(width, width);
}
protected void onDraw(Canvas canvas) {
float mDensity = context.getResources().getDisplayMetrics().density;
float mScaledDensity = context.getResources().getDisplayMetrics().scaledDensity;
Paint previewPaint = new Paint();
previewPaint.setColor(0x0C2727);
previewPaint.setAlpha(200);
previewPaint.setAntiAlias(true);
Paint previewTextPaint = new Paint();
previewTextPaint.setColor(Color.WHITE);
previewTextPaint.setAntiAlias(true);
previewTextPaint.setTextSize(90 * mScaledDensity);
previewTextPaint.setShadowLayer(5, 1, 2, Color.argb(255, 87, 87, 87));
float previewTextWidth = previewTextPaint.measureText(label);
// float previewTextHeight = previewTextPaint.descent() - previewTextPaint.ascent();
RectF previewRect = new RectF(0, 0, width, width);
canvas.drawRoundRect(previewRect, 5 * mDensity, 5 * mDensity, previewPaint);
canvas.drawText(label, (width - previewTextWidth)/2, previewRect.top - previewTextPaint.ascent(), previewTextPaint);
super.onDraw(canvas);
}
public void setLabel(String label) {
this.label = label;
Log.e(TAG, "Label: " + label);
this.invalidate();
}
}

detect clipping in android TextView

I have a TextView in my android application that has a set width on it. It's currently got a gravity of "center_horitonzal" and a set textSize (9sp). I pull values to put on this label from a sqlite database, and some of the values are too large to fit in the TextView at the current textSize.
Is there a way to detect that the text inside a TextView is going to be clipped? I'd like to detect this, and lower the font until it fits. There is a nice property in the iPhone UILabel that handles this called "adjustToFit" (which also has a minimum font size), and I'm basically trying to emulate that.
Here's an example of the TextView that I'm working with:
<TextView android:id="#+id/label5" android:layout_width="62px"
android:layout_height="wrap_content" android:layout_x="257px"
android:layout_y="169px" android:textSize="9sp"
android:textColor="#000"
android:typeface="sans" android:textStyle="bold"
android:gravity="center_horizontal" android:lines="1" />
I found a way to measure the width of text using the TextView's Paint object, and lower it until it fit in the size I needed. Here's some sample code:
float size = label.getPaint().measureText(item.getTitle());
while (size > 62) {
float newSize = label.getTextSize() - 0.5f;
label.setTextSize(newSize);
size = label.getPaint().measureText(item.getTitle());
}
Another way to do this (which might be equivalent) is something like this:
TextView title = new TextView(context) {
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int textsize = 30;
setTextSize(textsize);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
while (getMeasuredHeight() > MeasureSpec.getSize(heightMeasureSpec)) {
textsize--;
setTextSize(textsize);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
};
Just a warning that this seems to work, but I just threw it together - might be some edge cases in ways the TextView can be measured.
I wrote this function to trim off letters from the end of the text until it meets a certain width requirement.
The 0.38 function is setting the proportion of the screen I want to fill with this text, in this case, it was 38% since I wanted it to cover ~40% including padding. Worked for the cases I've tested it with.
Using this code to call the function below
DisplayMetrics metrics = new DisplayMetrics();
activity.getWindowManager().getDefaultDisplay().getMetrics(metrics);
double maxWidth = (double)metrics.widthPixels*0.38 - 1;
TextPaint painter = station.getPaint();
String left = item.getLocationName();
left = trimToLength(painter, left, maxWidth);
textView.setText(left);
This is the function
public String trimToLength(TextPaint painter, String initialText, double width)
{
String message = initialText;
String output = initialText;
float currentWidth = painter.measureText(output);
while (currentWidth > width)
{
message = message.substring(0, message.length()-1);
output = message + "...";
currentWidth = painter.measureText(output);
}
return output;
}

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