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How to remove the top and bottom space on textview of Android

开发者 https://www.devze.com 2023-03-17 20:11 出处:网络
When I include the below XML to layout file, I can see the below image. If you see it, you could 开发者_如何学Crealize that the TextView has top and bottom space.

When I include the below XML to layout file, I can see the below image. If you see it, you could 开发者_如何学Crealize that the TextView has top and bottom space.

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="E1"
android:background="#ff00ff00"/>

How to remove the top and bottom space on textview of Android

I wish to remove the space. How to remove it? What is it called? If anyone has clue.. please let me know. Thanks in advance.


Try android:includeFontPadding="false" to see if it helps. In my experience that will help a little bit, but there's no way of reducing the TextView dimensions to the exact pixel-perfect text size.

The only alternative, which may or may not give better results, is to cheat a bit and hard-wire the dimensions to match the text size, e.g. "24sp" instead of "wrap_content" for the height.


I had the same problem. Attribute android:includeFontPadding="false" does not work for me. I've solved this problem in this way:

public class TextViewWithoutPaddings extends TextView {

    private final Paint mPaint = new Paint();

    private final Rect mBounds = new Rect();

    public TextViewWithoutPaddings(Context context) {
        super(context);
    }

    public TextViewWithoutPaddings(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public TextViewWithoutPaddings(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @Override
    protected void onDraw(@NonNull Canvas canvas) {
        final String text = calculateTextParams();

        final int left = mBounds.left;
        final int bottom = mBounds.bottom;
        mBounds.offset(-mBounds.left, -mBounds.top);
        mPaint.setAntiAlias(true);
        mPaint.setColor(getCurrentTextColor());
        canvas.drawText(text, -left, mBounds.bottom - bottom, mPaint);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        calculateTextParams();
        setMeasuredDimension(mBounds.width() + 1, -mBounds.top + 1);
    }

    private String calculateTextParams() {
        final String text = getText().toString();
        final int textLength = text.length();
        mPaint.setTextSize(getTextSize());
        mPaint.getTextBounds(text, 0, textLength, mBounds);
        if (textLength == 0) {
            mBounds.right = mBounds.left;
        }
        return text;
    }
}


android:includeFontPadding="false" is pretty good but it does not get it precisely. sometimes you want border line accuracy so you can figure it out yourself by applying negative margins:

try setting your bottom and top margins to a negative value.

something like this:

android:layout_marginTop="-5dp"
android:layout_marginBottom="-5dp"

adjust the values accordingly.


This is the code that saved our day. It was adapted using mono C# code from maksimko:

public class TopAlignedTextView extends TextView {

    public TopAlignedTextView(Context context) {
        super(context);
    }

    /*This is where the magic happens*/
    @Override
    protected void onDraw(Canvas canvas){

        float offset = getTextSize() - getLineHeight();
        canvas.translate(0, offset);
        super.onDraw(canvas);
    }
}

Still had to play around with textView.setIncludeFontPadding(false) because we were aligning TextViews with different font sizes.


I faced the same problem. Here's a good answer: How to align the text to top of TextView?

But code is little unfinished and don't support all font sizes. Change the line

int additionalPadding = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 5, getContext().getResources().getDisplayMetrics());

to

int additionalPadding = getTextSize() - getLineHeight();

Complete C# code (mono) removes top offset:

public class TextControl : TextView {
    public TextControl (Context context) : base (context)
    {
        SetIncludeFontPadding (false);
        Gravity = GravityFlags.Top;
    }

    protected override void OnDraw (Android.Graphics.Canvas canvas)
    {
        if (base.Layout == null)
            return;

        Paint.Color = new Android.Graphics.Color (CurrentTextColor);
        Paint.DrawableState = GetDrawableState ();

        canvas.Save ();

        var offset = TextSize - LineHeight;
        canvas.Translate (0, offset);

        base.Layout.Draw (canvas);

        canvas.Restore ();
    }
}


Just wanted to add to DynamicMind's answer that the reason why you see spacing around your TextViews is padding in 9-patch backgrounds they use by default.

9-patch technology allows you to specify a content area which is, effectively, padding. That padding is used unless you set the view's padding explicitly. E.g., when you programmatically set a 9-patch background to a view which had paddings set, they are overridden. And vise-versa, if you set paddings they override what was set by 9-patch background.

Unfortunately, in the XML layout it's not possible to determine the order of these operations. I think just removing the background from your TextViews would help:

android:background="@null"


public class TopAlignedTextView extends TextView {

    public TopAlignedTextView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public TopAlignedTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs);
        setIncludeFontPadding(false); //remove the font padding
        setGravity(getGravity() | Gravity.TOP);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        TextPaint textPaint = getPaint();
        textPaint.setColor(getCurrentTextColor());
        textPaint.drawableState = getDrawableState();
        canvas.save();

        //remove extra font padding
        int yOffset = getHeight() - getBaseline();
        canvas.translate(0, - yOffset / 2);

        if (getLayout() != null) {
            getLayout().draw(canvas);
        }
        canvas.restore();
    }
}


Modified this answer a little bit to use kotlin class and extend AppCompatTextView, trimming vertical padding.

It allows setting android:fontFamily. Method calculateTextParams() moved from onDraw() for performance. Not tested for multiple lines of text:

import android.content.Context
import android.graphics.Canvas
import android.graphics.Rect
import android.util.AttributeSet
import androidx.appcompat.widget.AppCompatTextView

class NoPaddingTextView : AppCompatTextView
{
  private val boundsRect = Rect()
  private val textParams = calculateTextParams()

  constructor(context : Context?)
  : super(context)

  constructor(context : Context?, attrs : AttributeSet?)
  : super(context, attrs)

  constructor(context : Context?, attrs : AttributeSet?, defStyleAttr : Int)
  : super(context, attrs, defStyleAttr)

  override fun onDraw(canvas : Canvas)
  {
    with(boundsRect) {
      paint.isAntiAlias = true
      paint.color = currentTextColor
      canvas.drawText(textParams,
                      -left.toFloat(),
                      (-top - bottom).toFloat(),
                      paint)
    }
  }

  override fun onMeasure(widthMeasureSpec : Int, heightMeasureSpec : Int)
  {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec)
    calculateTextParams()
    setMeasuredDimension(boundsRect.width() + 1, -boundsRect.top + 1)
  }

  private fun calculateTextParams() : String
  {
    return text.toString()
    .also {text ->
      text.length.let {textLength ->
        paint.textSize = textSize
        paint.getTextBounds(text, 0, textLength, boundsRect)
        if(textLength == 0) boundsRect.right = boundsRect.left
      }
    }
  }
}


Have you defined a layout margin? For example:

android:layout_marginTop="5dp"

Otherwise, if your text view is wrapped inside a LinearLayout or other container, then that cold have either padding or a margin too.


android:background="@android:drawable/editbox_background"

use it according to you change it that you want editbox_background. because android provide some build in background like above code choose according to your requirement. May be it is help full to you.


Inside a LinearLayout the default padding might be an issue. Try setting it to 0dp. It worked for me.


The answer of TopAlignedTextView code:TopAlignedTextView@GitHub

use it by layout:

<com.github.captain_miao.view.TopAlignedTextView
    android:id="@+id/text_a"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:text="@string/text_demo_a"
/>

How to remove the top and bottom space on textview of Android


My way for fixing this is pretty hacky, but I managed to get the text to sit where I wanted by setting the height of the text view as static and fiddling with it until it just barely fit the text. In my case, the font style I was using had a height of 64sp so I set the height of my textview to 50sp and it worked okay. I also had to set foreground_gravity to bottom.


android:includeFontPadding="false"
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