Android：椭圆形看起来很糟糕

Question

I have a button with a oval background and it doesn't look like a perfect circle, I can notice at every distance "breaks" in the circunfrence, this is how it looks

the background:

<shape android:shape="oval"
xmlns:android="http://schemas.android.com/apk/res/android" >

<solid android:color="#7eadb6"/>
<size android:height="80dp"
    android:width="80dp"/>

Edit: Creating the button

static Button theButton1;
final LinearLayout.LayoutParams params = new LinearLayout.LayoutParams
            (80, 80);

theButton1 = new Button(getActivity());
theButton1.setBackgroundResource(R.drawable.subject_button);
theButton1.setLayoutParams(params);
theButton1.setTextColor(Color.parseColor("#ffffff"));
theButton1.setTextSize(23);
theButton1.setText(prefs.getString("text1", "").substring(0, 1));
theButton1.setOnClickListener(this);

Is this normal? If not how can i fix it?

Note: I have more than one button created like this

Answer 1

This might be an anti-aliasing issue. You have to disable hardware acceleration for it. Try this-

<shape android:shape="oval"
xmlns:android="http://schemas.android.com/apk/res/android"
android:hardwareAccelerated="false"
>

<solid android:color="#7eadb6"/>
<size android:height="80dp"
    android:width="80dp"/>
</shape>

UPDATE:

You will also have to set the layer type of button to software.

theButton1.setLayerType(View.LAYER_TYPE_SOFTWARE, null);

after you set the layout params.

Answer 2

Wrong question leads to wrong answers !!!

By reading your comments, i understand you want to achieve such a thing at last

A circle with a text on it .

you can easily reach your aim by using TextDrawable Library

Now lets back to your problem, the problem is Surely just because Anti Aliasing. Your problem become even worse on l-dpi devices.

The trick is making a bitmap and pass it as background of your desired view.

public Bitmap getCircleBitmap(int dimenSize,int mColor) {
    Bitmap output = Bitmap.createBitmap(dimenSize, dimenSize, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(output);
    int x = dimenSize;
    int y = dimenSize;
    Paint paint = new Paint();
    paint.setAntiAlias(true);
    paint.setStyle(Paint.Style.FILL);
    paint.setColor(Color.TRANSPARENT);
    canvas.drawPaint(paint);
    canvas.drawBitmap(output, 0.0f, 0.0f, paint);
    paint.setColor(mColor);
    canvas.drawCircle(x / 2, y / 2, dimenSize/2, paint);
    return output;
}

Now you have a SHARP circle bitmap and can easily use it.

Answer 3

Update just update your Button in the xml file like this:

<Button
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:text="mytext"
    android:id="@+id/button"
     />

and Keep in your activity :

theButton1 = new Button(getActivity());
theButton1.setBackgroundResource(R.drawable.subject_button);
theButton1.setTextColor(Color.parseColor("#ffffff"));
theButton1.setTextSize(23);
theButton1.setText(prefs.getString("text1", "").substring(0, 1));
theButton1.setOnClickListener(this);

Answer 4

i dont think something is wrong with your implementation. but try doing it in xml, because it might be causing issues while doing all this at run time. create a button and set its background as your oval shape drawable

<Button
android:layout_width="50dp"
android:layout_height="50dp"
android:background="@drawable/oval"
android:gravity="center_vertical|center_horizontal"
android:text="button text here"
/>

Answer 5

There is no issue with drawable.

ovelshape.xml

  <shape android:shape="oval"
    xmlns:android="http://schemas.android.com/apk/res/android" >

    <solid android:color="#7eadb6"/>

In your XML you need to provide the height & width in dp. And use View instead of Button. I don't no why but it works for me.

<View android:layout_width="50dp"
    android:layout_height="50dp"
    android:background="@drawable/ovelshape"/>