Android example source code file (Marble.java)

This example Android source code file (Marble.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, drawing, graphics, marble, paint, ui, view

The Marble.java Android example source code

/*
 * Copyright (C) 2008 Jason Tomlinson.
 *
 * 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.example.amazed;

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.view.View;

/**
 * Marble drawn in the maze.
 */
public class Marble {

    // View controlling the marble.
    private View mView;

    // marble attributes
    // x,y are private because we need boundary checking on any new values to
    // make sure they are valid.
    private int mX = 0;
    private int mY = 0;
    private int mRadius = 8;
    private int mColor = Color.WHITE;
    private int mLives = 5;

    /**
     * Marble constructor.
     * 
     * @param view
     *            View controlling the marble
     */
    public Marble(View view) {
        this.mView = view;
        init();
    }

    /**
     * Setup marble starting co-ords.
     */
    public void init() {
        mX = mRadius * 6;
        mY = mRadius * 6;
    }

    /**
     * Draw the marble.
     * 
     * @param canvas
     *            Canvas object to draw too.
     * @param paint
     *            Paint object used to draw with.
     */
    public void draw(Canvas canvas, Paint paint) {
        paint.setColor(mColor);
        canvas.drawCircle(mX, mY, mRadius, paint);
    }

    /**
     * Attempt to update the marble with a new x value, boundary checking
     * enabled to make sure the new co-ordinate is valid.
     * 
     * @param newX
     *            Incremental value to add onto current x co-ordinate.
     */
    public void updateX(float newX) {
        mX += newX;

        // boundary checking, don't want the marble rolling off-screen.
        if (mX + mRadius >= mView.getWidth())
            mX = mView.getWidth() - mRadius;
        else if (mX - mRadius < 0)
            mX = mRadius;
    }

    /**
     * Attempt to update the marble with a new y value, boundary checking
     * enabled to make sure the new co-ordinate is valid.
     * 
     * @param newY
     *            Incremental value to add onto current y co-ordinate.
     */
    public void updateY(float newY) {
        mY -= newY;

        // boundary checking, don't want the marble rolling off-screen.
        if (mY + mRadius >= mView.getHeight())
            mY = mView.getHeight() - mRadius;
        else if (mY - mRadius < 0)
            mY = mRadius;
    }

    /**
     * Marble has died
     */
    public void death() {
        mLives--;
    }

    /**
     * Set the number of lives for the marble
     * 
     * @param Number
     *            of lives
     */
    public void setLives(int val) {
        mLives = val;
    }

    /**
     * @return Number of lives left
     */
    public int getLives() {
        return mLives;
    }

    /**
     * @return Current x co-ordinate.
     */
    public int getX() {
        return mX;
    }

    /**
     * @return Current y co-ordinate.
     */
    public int getY() {
        return mY;
    }
}