How to change hint text size without changing the

问题:

I have a EditText input field. I have added a hint in it. Now i want to change the size of hint text, but when i do this, it also effects the size of the text. Kindly guide me how to change the size of hint and text separately, and give different fonts to both the hint and the text.

<EditText
    android:layout_width="0dp"
    android:layout_height="50dp"
    android:layout_weight="1"
    android:textSize="12sp"
    android:textColor="#ffffff"                            
    android:fontFamily="sans-serif-light"
    android:hint="MM/YY"
    android:textColorHint="@color/white" />  

回答1:

The hint and the text are exclusive, if one of them is visible, the other one is not.

Because of this, you could just change the attributes of your EditText depending on if it's empty (the hint is visible) or not (the text is visible).

For example:

final EditText editText = (EditText) findViewById(R.id.yourEditText);

editText.addTextChangedListener(new TextWatcher() {
    boolean hint;

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        if(s.length() == 0) {
            // no text, hint is visible
            hint = true;
            editText.setTextSize(TypedValue.COMPLEX_UNIT_SP, 12);
            editText.setTypeface(Typeface.createFromAsset(getAssets(),
                "hintFont.ttf")); // setting the font
        } else if(hint) {
            // no hint, text is visible
            hint = false;
            editText.setTextSize(TypedValue.COMPLEX_UNIT_SP, 16);
            editText.setTypeface(Typeface.createFromAsset(getAssets(),
                "textFont.ttf")); // setting the font
        }
    }

    @Override
    public void afterTextChanged(Editable s) {
    }
});

回答2:

You can set it in resource file.

For example:

<string name="hint"><font size="20">Hint!</font></string>

And your XML:

android:hint="@string/hint"

回答3:

You could set the text size to the smaller, desired value, then set a text listener to change the text size after some text is entered.

回答4:

Using HTML is ok, but it is not flexible. For example, you cannot set the exact size. I will provide an alternative solution where you can set:

• new Hint font
• new Hint size
• new Hint style

1) Create a custom Hint object:

import android.graphics.Typeface;
import android.text.SpannableString;
import android.text.Spanned;
import android.text.style.MetricAffectingSpan;

public class CustomHint extends SpannableString
{
    public CustomHint(final CharSequence source, final int style)
    {
        this(null, source, style, null);
    }

    public CustomHint(final CharSequence source, final Float size)
    {
        this(null, source, size);
    }

    public CustomHint(final CharSequence source, final int style, final Float size)
    {
        this(null, source, style, size);
    }

    public CustomHint(final Typeface typeface, final CharSequence source, final int style)
    {
        this(typeface, source, style, null);
    }

    public CustomHint(final Typeface typeface, final CharSequence source, final Float size)
    {
        this(typeface, source, null, size);
    }

    public CustomHint(final Typeface typeface, final CharSequence source, final Integer style, final Float size)
    {
        super(source);

        MetricAffectingSpan typefaceSpan = new CustomMetricAffectingSpan(typeface, style, size);
        setSpan(typefaceSpan, 0, source.length(), Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
    }
}

2) Create custom MetricAffectingSpan object:

import android.graphics.Typeface;
import android.text.TextPaint;
import android.text.style.MetricAffectingSpan;

public class CustomMetricAffectingSpan extends MetricAffectingSpan
{
    private final Typeface _typeface;
    private final Float    _newSize;
    private final Integer  _newStyle;

    public CustomMetricAffectingSpan(Float size)
    {
        this(null, null, size);
    }

    public CustomMetricAffectingSpan(Float size, Integer style)
    {
        this(null, style, size);
    }

    public CustomMetricAffectingSpan(Typeface type, Integer style, Float size)
    {
        this._typeface = type;
        this._newStyle = style;
        this._newSize = size;
    }

    @Override
    public void updateDrawState(TextPaint ds)
    {
        applyNewSize(ds);
    }

    @Override
    public void updateMeasureState(TextPaint paint)
    {
        applyNewSize(paint);
    }

    private void applyNewSize(TextPaint paint)
    {
        if (this._newStyle != null)
            paint.setTypeface(Typeface.create(this._typeface, this._newStyle));
        else
            paint.setTypeface(this._typeface);

        if (this._newSize != null)
            paint.setTextSize(this._newSize);
    }
}

3) Use:

Typeface newTypeface = Typeface.createFromAsset(getAssets(), "AguafinaScript-Regular.ttf");
CustomHint customHint = new CustomHint(newTypeface, "Enter some text", Typeface.BOLD_ITALIC, 60f);
        //        CustomHint customHint = new CustomHint(newTypeface, "Enter some text", Typeface.BOLD_ITALIC);
        //        CustomHint customHint = new CustomHint(newTypeface, "Enter some text", 60f);
        //        CustomHint customHint = new CustomHint("Enter some text", Typeface.BOLD_ITALIC, 60f);
        //        CustomHint customHint = new CustomHint("Enter some text", Typeface.BOLD_ITALIC);
        //        CustomHint customHint = new CustomHint("Enter some text", 60f);

customEditText.setHint(customHint);