How to add chips from Material Components library

问题:

I've seen that in android-P google add new material components library which contains material chips:

Material components for android

Material.io chips usage

Material components on GitHub

So I decided to add material input chips to my project, but unfortunately didn't find any tutorial how to make that. I want to create something like Gmail chips but without image on the start.

Because I'm using appcompat library I tried to use material chips by android.support.design.chip.Chip and android.support.design.chip.ChipGroup. But result was just chips without any input field. Also I tried to create a Standalone ChipDrawable and then add it to EditText using

Editable text = editText.getText();

text.setSpan(span, 0, text.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);

But I got empty EditText without any chips. So how can I create chips input like in Gmail using this material components library? Maybe someone has expreience or knows any tutorials where I could see how to create this?

Thanks in advance!

回答1:

Answer

No default input field for adding chips in android. They mentioned input chips but i didn't find any layout or viewgroup for input chips. So i do with Chipdrawable method to add chips in edittext. Here am using AppCompatEdittext you can change to anyview which listening the text inputs. Reference.

Step 1

Add chip xml resource. chip.xml

res -> xml -> chip.xml

<?xml version="1.0" encoding="utf-8"?>
<chip xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:app="http://schemas.android.com/apk/res-auto"
 android:textAppearance="@style/ChipTextApperance"
 app:chipBackgroundColor="@color/colorAccent"
 app:chipIcon="@drawable/ic_call_white_24dp"
 app:closeIconEnabled="true"  <!--property for close icon if no need set to false. -->
 app:closeIconTint="@android:color/white" />

Then add textappearance style in style.xml(For change textStyle)

<style name="ChipTextApperance" parent="TextAppearance.MaterialComponents.Chip">
    <item name="android:textColor">@android:color/white</item>
</style>

Step 2

Add your view here am using AppCompatEdittext

  <android.support.v7.widget.AppCompatEditText
    android:id="@+id/phone"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_marginEnd="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginRight="8dp"
    android:layout_marginStart="8dp"
    android:layout_marginTop="8dp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/tvt_Contact" />

Step 3
Add this code to your view to get the desired behaviour.

 private int SpannedLength = 0,chipLength = 4;

 AppCompatEditText Phone = findViewById(R.id.phone);

 Phone.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
            if (charSequence.length() == SpannedLength - chipLength)
            {
                SpannedLength = charSequence.length();
            }
        }

        @Override
        public void afterTextChanged(Editable editable) {

            if(editable.length() - SpannedLength == chipLength) {
                ChipDrawable chip = ChipDrawable.createFromResource(getContext(), R.xml.chip);
                chip.setChipText(editable.subSequence(SpannedLength,editable.length()));
                chip.setBounds(0, 0, chip.getIntrinsicWidth(), chip.getIntrinsicHeight());
                ImageSpan span = new ImageSpan(chip);
                editable.setSpan(span, SpannedLength, editable.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                SpannedLength = editable.length();
            }

        }
    });

Change chipLength according to your need when new chip need to be added in edittext.

OUTPUT

EDITED

You can find more about how to align center the text with span Here.

Here i added some code from the solution will fix for you..

public class VerticalImageSpan extends ImageSpan {

public VerticalImageSpan(Drawable drawable) {
    super(drawable);
}

@Override
public int getSize(@NonNull Paint paint, CharSequence text, int start, int end,
                   Paint.FontMetricsInt fontMetricsInt) {
    Drawable drawable = getDrawable();
    Rect rect = drawable.getBounds();
    if (fontMetricsInt != null) {
        Paint.FontMetricsInt fmPaint = paint.getFontMetricsInt();
        int fontHeight = fmPaint.descent - fmPaint.ascent;
        int drHeight = rect.bottom - rect.top;
        int centerY = fmPaint.ascent + fontHeight / 2;

        fontMetricsInt.ascent = centerY - drHeight / 2;
        fontMetricsInt.top = fontMetricsInt.ascent;
        fontMetricsInt.bottom = centerY + drHeight / 2;
        fontMetricsInt.descent = fontMetricsInt.bottom;
    }
    return rect.right;
}

@Override
public void draw(@NonNull Canvas canvas, CharSequence text, int start, int end,
                 float x, int top, int y, int bottom, @NonNull Paint paint) {

    Drawable drawable = getDrawable();
    canvas.save();
    Paint.FontMetricsInt fmPaint = paint.getFontMetricsInt();
    int fontHeight = fmPaint.descent - fmPaint.ascent;
    int centerY = y + fmPaint.descent - fontHeight / 2;
    int transY = centerY - (drawable.getBounds().bottom - drawable.getBounds().top) / 2;
    canvas.translate(x, transY);
    drawable.draw(canvas);
    canvas.restore();
}

}

And change your imagespan class like below

VerticalImageSpan span = new VerticalImageSpan(chip);

回答2:

We can do this by using material chips design itself without adding any extra styles.

Add it on app gradle For AndroidX

implementation 'com.google.android.material:material:1.0.0-beta01'

For earlier than AndroidX use this

implementation 'com.android.support:design:28.0.0'

Fragment

class EntryChipDemoFragment : Fragment() {
    private lateinit var mView: View

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {
        mView = inflater.inflate(R.layout.fragment_entry_chip_demo, container, false)

        mView.etValue.setOnEditorActionListener(TextView.OnEditorActionListener { v, actionId, _ ->
            if (actionId == EditorInfo.IME_ACTION_DONE) {
                val txtVal = v.text
                if(!txtVal.isNullOrEmpty()) {
                    addChipToGroup(txtVal.toString(), mView.chipGroup2)
                    mView.etValue.setText("")
                }

                return@OnEditorActionListener true
            }
            false
        })

        return mView
    }


    private fun addChipToGroup(txt: String, chipGroup: ChipGroup) {
        val chip = Chip(context)
        chip.text = txt
//        chip.chipIcon = ContextCompat.getDrawable(requireContext(), baseline_person_black_18)
        chip.isCloseIconEnabled = true
        chip.setChipIconTintResource(R.color.chipIconTint)

        // necessary to get single selection working
        chip.isClickable = false
        chip.isCheckable = false
        chipGroup.addView(chip as View)
        chip.setOnCloseIconClickListener { chipGroup.removeView(chip as View) }
        printChipsValue(chipGroup)
    }

    private fun printChipsValue(chipGroup: ChipGroup) {
        for (i in 0 until chipGroup.childCount) {
            val chipObj = chipGroup.getChildAt(i) as Chip
            Log.d("Chips text :: " , chipObj.text.toString())

        }
    }

    companion object {
        @JvmStatic
        fun newInstance() = EntryChipDemoFragment()
    }
}

XML File:

<HorizontalScrollView
    android:id="@+id/chipGroup2HorizontalView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="8dp"
    android:layout_marginTop="16dp"
    android:scrollbars="none"
    app:layout_constraintVertical_bias="0.62">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center_vertical"
        android:orientation="horizontal">

        <androidx.appcompat.widget.AppCompatTextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Skills: " />

        <com.google.android.material.chip.ChipGroup
            android:id="@+id/chipGroup2"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:duplicateParentState="false">

        </com.google.android.material.chip.ChipGroup>

        <com.google.android.material.textfield.TextInputLayout
            android:id="@+id/textInputLayout"
            android:layout_width="wrap_content"
            android:layout_height="43dp"
            android:layout_marginStart="8dp"
            android:layout_marginEnd="8dp"
            android:layout_marginBottom="5dp"
            android:minWidth="32dp"
            android:visibility="visible"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toEndOf="@id/chipGroup2HorizontalView"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintWidth_min="32dp">

            <androidx.appcompat.widget.AppCompatEditText
                android:id="@+id/etValue"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:background="@android:color/transparent"
                android:imeOptions="actionDone"
                android:maxLines="1"
                android:singleLine="true" />

        </com.google.android.material.textfield.TextInputLayout>

    </LinearLayout>


</HorizontalScrollView>

For more reference Click Here

回答3:

You can use material chip "com.google.android.material.chip.Chip" and "implementation 'com.google.android.material:material:1.0.0' " add in build.gradle

Filter style="@style/Widget.MaterialComponents.Chip.Filter"

Choice Chips style="@style/Widget.MaterialComponents.Chip.Choice"

Entry input: style="@style/Widget.MaterialComponents.Chip.Entry"