java/src/com/android/inputmethod/latin/setup/SetupStepIndicatorView.java

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.inputmethod.latin.setup;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.View;

import com.android.inputmethod.compat.ViewCompatUtils;
import com.android.inputmethod.latin.R;

public final class SetupStepIndicatorView extends View {
    private final Path mIndicatorPath = new Path();
    private final Paint mIndicatorPaint = new Paint();
    private float mXRatio;

    public SetupStepIndicatorView(final Context context, final AttributeSet attrs) {
        super(context, attrs);
        mIndicatorPaint.setColor(getResources().getColor(R.color.setup_step_background));
        mIndicatorPaint.setStyle(Paint.Style.FILL);
    }

    public void setIndicatorPosition(final int stepPos, final int totalStepNum) {
        final int layoutDirection = ViewCompatUtils.getLayoutDirection(this);
        // The indicator position is the center of the partition that is equally divided into
        // the total step number.
        final float partionWidth = 1.0f / totalStepNum;
        final float pos = stepPos * partionWidth + partionWidth / 2.0f;
        mXRatio = (layoutDirection == ViewCompatUtils.LAYOUT_DIRECTION_RTL) ? 1.0f - pos : pos;
        invalidate();
    }

    @Override
    protected void onDraw(final Canvas canvas) {
        super.onDraw(canvas);
        final int xPos = (int)(getWidth() * mXRatio);
        final int height = getHeight();
        mIndicatorPath.rewind();
        mIndicatorPath.moveTo(xPos, 0);
        mIndicatorPath.lineTo(xPos + height, height);
        mIndicatorPath.lineTo(xPos - height, height);
        mIndicatorPath.close();
        canvas.drawPath(mIndicatorPath, mIndicatorPaint);
    }
}